WO2022200362A2

WO2022200362A2 - Cultivation floor system and method

Info

Publication number: WO2022200362A2
Application number: PCT/EP2022/057512
Authority: WO
Inventors: Hugo Willem Lambertus PAANS
Original assignee: Erfgoed Nederland B.V.
Priority date: 2021-03-24
Filing date: 2022-03-22
Publication date: 2022-09-29
Also published as: WO2022200362A3; EP4312509A2

Abstract

A cultivation floor system with a floor on which plant containers are placed. The cultivation floor system comprises a watertight basin and a water-permeable structure in the basin. The water-permeable structure is covered by a permeable top fabric which forms the floor onto which the plant containers are placed. The structure has one or more layers of granular material, such as for example of volcanic rock, e.g. lava granules. Preferably, as is also the case in known systems, the top fabric is a woven top fabric having small pores between the yarns of the top fabric. A perforated film is placed between the permeable top fabric on the one hand and the permeable structure on the other hand. The perforated film is made of impermeable film material which is provided with distributed perforations in such a manner that the film reduces the free evaporation surface for water from the permeable structure.

Description

P34758PC00

CULTIVATION FLOOR SYSTEM AND METHOD

A first aspect of the invention relates to a cultivation floor system with a floor on which plant containers are placeable. The cultivation floor system comprises a watertight basin and a water-permeable structure in the basin. The water-permeable structure is covered by a permeable top fabric which forms the floor onto which the plant containers are to be placed. The structure has one or more layers of granular material, for example of volcanic rock, e.g. lava granules. Preferably, as is also the case in known systems, the top fabric is a woven top fabric having small pores between the yarns of the top fabric. A perforated film is placed between the permeable top fabric on the one hand and the water-permeable structure on the other hand. The perforated film is made of impermeable film material which is provided with distributed perforations in such a manner that the film reduces the free evaporation surface for water from the permeable structure.

The system furthermore comprises an ebb/flood watering installation which is configured to supply water so that water is available for the plants in the plant containers placed on the floor. This installation comprises one or more irrigation lines on the bottom of the basin covered by the water-permeable structure, which irrigation lines have openings along their length. The installation is configured for water to flow from the one or more irrigation lines to flood the basin to a level above the permeable top fabric and to relief water from the basin.

A cultivation floor system according to the preamble of claim 1 is known from EP2955996. In practice, undesirable effects occasionally may occur during use of such cultivation floor system.

One problem is that plant roots may grow more than desired when the plant containers are placed on the cultivation floor. This results in plant roots protruding below from the plant containers. This has a number of adverse effects. For example, the plant containers look less appealing and the plant containers are less stable on the floor due to the protruding roots.

The first aspect of the invention is aimed at providing an improved cultivation floor system, by means of which the above mentioned problem can be alleviated.

The first aspect of the invention provides a cultivation floor system according to the preamble of claim 1, which is characterized in that the cultivation floor system further comprises a gas supply and distribution system, for example for supply of air and/or CO2, wherein the gas supply and distribution system comprises a network of gas supply lines distinct from the irrigation lines and configured for distributing a gas across the floor, which network is provided in the basin lower than the perforated film, preferably embedded in the water- permeable structure or on the bottom of the basin, and wherein the gas supply and distribution system further comprises a gas supplying installation for supplying gas to the network so that, in use, the gas flows from the network through the perforations of the perforated film and reaches the plant containers placed on the floor.

The network is provided below the perforated film, e.g. at least 5 centimeters below the film, generally between the bottom of the basin and the perforated film. For example, the network is provided embedded in the water-permeable structure in the basin, for example, in a granular layer of the water-permeable structure or on the bottom of the basin.

The first aspect of the invention is based on the insight that plant roots grow when they are in contact with water. Due to the growing conditions provided for the plant, e.g. in a greenhouse, the plant roots need little water to start growing. A second insight is that the plant roots remain moist even when the water has flowed out of the basin. This causes the plant roots to grow even after watering the plants resulting in the protruding plant roots.

The gas supply and distribution system, for example, allows the roots of the plants to be dried after the water has flowed out of the basin by distributing the gas across the floor and allowing it to flow to the plant containers placed on the floor. By placing the network below the perforated film the gas is distributed homogeneously over the surface of the floor. This allows the roots of plants in plant containers placed on the floor to be dried homogeneously providing a homogenous effect over the extent of the floor, which enhances uniformity and quality of the plants that are cultivated.

Furthermore, by distributing the gas through the floor structure, the roots of the plants in the containers are more effectively reached. By controlling the moist levels of the roots by virtue of operation of the watering system in combination with the gas supply and distribution system the growth of the roots may be controlled. Thus, in practice, after cultivation the plants may have strong roots which do not or not unduly protrude from the plant containers.

Another advantage of the first aspect of the invention is that by supplying a gas, such as air, by the gas supply and distribution system to the cultivation floor growth of the plants may be controlled, e.g. improved. The growth may be controlled by controlling the temperature of the gas, the composition of the gas and/or the humidity of the gas.

A further advantage of the first aspect of the invention is that by supplying a gas, such as air, by the gas supplying and distribution system parts of the cultivation floor system, such as e.g. the permeable top cloth, may be dried by the gas. This allows for further control of conditions of the cultivation floor system.

The system according to the first aspect of the invention is advantageously placed in a greenhouse.

The gas supply and distribution system may be used to supply a gas, for example air, e.g. conditioned air, O2 and/or CO2, to the floor in order to provide a better climate for the plants to grow in. The gas may further be a gas composition designed to stimulate the growth of the plants contained in the plant containers or which activates flower induction of the plants in the plant containers. The gas may be supplied at a rate of 2-10 m3/m² per hour, e.g. 5 m3/m² per hour. Herein m2 relates to the surface of the floor.

For example, in operation, the gas supply and distribution system may supply air, e.g. low humidity air, in order to dry the floor surface and remove residual water that could trigger undue growth of the roots of the plants.

For example, in operation, the gas supply and distribution system may supply CO2 or a mixture of air and CO2 in order to enhance growth of the plants.

The gas supply and distribution system may be used to supply conditioned air to influence temperature and/or humidity of the zone where the plants are growing. For example, cooled air is supplied in order to cool the zone, e.g. in a greenhouse where the air above the zone has a higher temperature, e.g. in summer

In an embodiment, the gas is air that has been sanitized, e.g. passed through a sanitizing apparatus prior to introduction into the network, which apparatus removes and/or denaturizes small organisms, e.g. mold spores and other spores, pollen, bacteria, and/or mildew, etc. Thus the system allows for a more versatile control of the conditions wherein plants in plant containers are grown. In an embodiment, perforations are provided in the permeable top fabric, e.g. which are located on top of perforations in the perforated film, such that the perforations in the permeable top fabric and the perforations in the perforated film form gas channels which allow gas to effectively flow therethrough. For example, the top fabric and the film are locally welded to each other, with one or more perforations being located in each welded zone, e.g. formed simultaneously with the provision of the weld.

In an embodiment, the network of gas supply lines is provided at least 5 cm below the top fabric. This allows the gas to flow optimally from the network through the perforations of the perforated film to plant containers placed on the floor. If the network is provided too close to the top fabric the gas may not be equally distributed over the surface of the floor.

In an embodiment, the distributed perforations of the perforated film have an average opening of between 0.75 mm² and 108 mm², wherein the perforations form, preferably, at most 10% of the surface area of the perforated film. The film prevents water, which may remain behind in the water-permeable structure after the water has been let out of the basin, from evaporating, which may lead to the growth of algae in the cultivation floor system, e.g. in or on the top fabric. It is found in experiments that distributed perforations in the film with an average opening according to this embodiment allow for a good water supply to the plants while also preventing water from evaporating unduly from the water-permeable structure.

In an embodiment, the network for distributing gas is embedded in one of the one or more layers of the water-permeable structure. For example, the network is embedded in a granular layer of the water-permeable structure. The granular layer provides for enhanced distribution of the gas. In another embodiment, (part of) the network for distributing gas is embedded in the bottom of the basin. This may reduce the overall height of the cultivation floor.

In an embodiment, the network for distributing gas is kept at an overpressure by the gas.

This allows for a uniform distribution of gas.

In an embodiment, the irrigation lines are placed parallel in the basin, for example in a longitudinal direction of the longitudinal basin, e.g. the basin extending between parallel rows of roof-supporting columns of a greenhouse.

Preferably, the irrigation lines are distributed evenly in the basin, e.g. parallel to one another. This allows the water to rise and fall evenly through the entire basin. It further allows the water to enter and leave the basin efficiently and swiftly. In an embodiment, the network comprises one or more perforated gas distribution lines each having along the length thereof perforations for emitting the gas, e.g. with an inlet connected to a main gas pipe and with a closed end. For example, multiple perforated gas distribution lines extend parallel to one another from a common main gas pipe, e.g. perpendicular to the main gas pipe.

In an embodiment, the watering installation comprises multiple parallel irrigation lines and the one or more main gas pipes extend parallel to the irrigation lines, e.g. each main gas pipe centered between a pair of adjacent irrigation lines. Perforated gas distribution lines branch off from each main gas pipe, e.g. in opposite directions, e.g. perpendicular to the main gas pipe.

In an embodiment, the network comprises a main gas pipe, e.g. which extends parallel to the irrigation lines, e.g. centered between a pair of irrigation lines, and perforated gas distribution lines that branch off from the main gas pipe in opposite directions, e.g. perpendicular to the main gas pipe. In other embodiments it is possible that the main gas pipe is not parallel to the irrigation line and/or that the perforated gas distribution lines are not perpendicular to the main gas pipe and/or the irrigation lines.

In an embodiment, the network comprises a main gas pipe, e.g. which extends parallel to the irrigation lines, e.g. centered between a pair of irrigation lines. The perforated gas distribution lines branch off from the main gas pipe in opposite directions, e.g. perpendicular to the main gas pipe, each perforated gas distribution line having a blind end and a length of between 3 and 5 meters.

For example, the system is installed in a greenhouse having parallel rows of roof-support columns spaced 8 meters from one another.

In an embodiment, the network for distributing gas comprises perforated gas distribution lines having along the length thereof perforations for emitting the gas, e.g. with an inlet connected to a main gas pipe and with a closed end, wherein multiple perforated gas distribution lines extend, e.g. parallel to one another from a common main gas pipe, e.g. perpendicular to the main gas pipe, and wherein a flow rate adjusting device is present at the inlet of each perforated gas distribution line. For example, the device allows for setting the flow rate upon installation of the floor system. The perforated gas distribution lines can be embodied as perforated pipes and/or perforated hoses.

An effect of arranging perforated gas distribution lines at an angle, e.g. perpendicular, to the irrigation lines is that the perforated lines do not interfere unduly with the flow of water in the permeable structure. For example, when arranged on the bottom, this orientation prevents formation of puddles in the basin which may negatively influence the performance of the cultivation floor system.

The perforated pipes and/or hoses may have, in practical embodiments, a diameter between 15 - 35 mm, for example between 20-30 mm, for example 25 mm.

For example, the perforated pipes and/or hoses are evenly distributed in the cultivation floor, e.g. they are provided parallel to each other at intervals of 0.5 - 1.5 meter, e.g. of 1 meter.

The perforations in the pipes and/or hoses may be provided at intervals between 10 - 200, e.g. 60 - 200 cm, for example at 80 cm.

The perforations in the gas distribution network may have a diameter between 0,5 - 5 mm, for example between 2 - 4 mm.

In an example, the irrigation lines are provided parallel to one another and in the longitudinal direction of the basin. A main gas pipe which is part of the network for distributing gas is provided in the longitudinal direction below the perforated film, e.g. between the perforated film and the bottom of the basin, e.g. embedded in the granular material filled in the basin. In this embodiment, the perforated pipes and/or hoses are connected to the main gas pipe which supplies the gas to the perforated pipes and/or hoses.

For example, the cultivation floor system may be provided in a greenhouse with a width of 8 meter between rows of roof-supporting columns. Herein, the gas supplying line may be provided in a longitudinal direction in the middle of the width of the section of the greenhouse such that the perforated pipes and/or hoses extend about 4 meters in either direction of the gas supplying line. An effect of having relatively short individual perforated hoses and/or pipes is that a more or less equal amount of gas may flow through each perforation of the perforated pipes and/or hoses. In an embodiment, the gas supply lines of the gas supply and distribution system are provided inside the irrigation lines of the watering installation. For example, the irrigation lines in this embodiment may be placed parallel in the basin and the gas supply lines may be provided inside the irrigation lines. This allows for easier installation of the system. It may also allow for a more compact gas supply network and irrigation system in the basin.

In an embodiment, a gas supply line is nested within an irrigation line. For example, a cultivation floor system is provided with multiple parallel irrigation lines, each connected at one end thereof to common main irrigation line and extending to a blind end, wherein in each irrigation line a perforated gas distribution line is nested allowing to distribution gas over the length of the gas distribution line, which gas emerges via the openings in the irrigation line so that the gas is distributed across the floor. For example, gas is supplied only when no water is supplied via the irrigation lines, or gas is supplied simultaneous with the supply of water. This nesting of a gas distribution line in an irrigation line allows to retrofit existing cultivation floors that have multiple parallel irrigation lines, each connected at one end thereof to common main irrigation line and extending to a blind end, with a gas supply and distribution system according to the first aspect of the invention. The gas distribution line can be shoved into the irrigation line, which is simple to do. It is noted that provision of gas distribution lines merely within irrigation lines may lead to a suboptimal distribution of the gas for some situations. Yet, it may be acceptable, e.g. in case the gas supplied is primarily used to create specific conditions just above the floor, e.g. below the leaves of the plants placed on the floor.

In an embodiment, the network is supported at a distance above the bottom of the basin by spacers, and then embedded in granular material. This allows water to flow underneath the network into and out of the basin. The spacers may be concrete or plastic spacers. In embodiments the spacers are separate spacers that are placed on the bottom of the basin.

In an embodiment, the gas supplying installation comprises a blower to supply air to the network.

In an embodiment, the gas supply and distribution system is adapted to heat or cool the gas before distributing the gas over the surface of the floor. By bringing the gas to a desired temperature before distributing the gas over the surface of the floor, the growth conditions of the plants in the plant containers may be better controlled, e.g. by better controlling the climate wherein the plants grow. In particular the air zone directly above the floor and under the leaves of the plants can be effectively controlled/influenced in this manner. This allows for more versatile and efficient growing of the plants.

In embodiments, the network for distributing gas may be split in separate networks for distributing gas, for example which are provided in different parts of the cultivation floor system, such that one part of the surface of the cultivation floor is supplied with warmer gas and another part of the surface of the floor is supplied with cooler gas. This allows to create ideal conditions for different plant varieties.

The first aspect of the invention is also related to a method wherein use is made of a cultivation floor system according to the first aspect of the invention.

In embodiments, the gas supply and distribution system is operated to reduce or avoid growth of roots out of the container, e.g. by effecting or enhancing a drying out of the floor.

In embodiments, the cultivation floor system may be used to vary the period and/or interval of supplying gas to the cultivation floor, e.g. based on the amount of water supplied to the cultivation floor. It may be advantageous to supply gas to the cultivation floor, and the plant containers placed thereon, following watering the plants, e.g. to dry the roots of the plants.

In embodiments, the cultivation floor system may be used to supply additional CO2 to the plants contained in the plant containers to improve growth conditions for the plants. In embodiments, the cultivation floor system may be used to supply O2 to the plants contained in the plant containers. In embodiments, the cultivation floor system may be used to supply air to the plants contained in the plant containers. In embodiments, the humidity level of the gas may be controlled.

In embodiments, gas is supplied to the cultivation floor on regular intervals, e.g. gas is supplied for 1 hour with 1 hour intervals, e.g. gas is supplied to the cultivation floor for a period of more than 24 hours without interruption. The amount of gas provided, frequency of supplying gas, and composition of gas provided may depend on the plant variety and plant size to be grown on the cultivation floor.

The first aspect of the invention further relates to a method for installing a cultivation floor system according to claim 14. The invention also relates to a cultivation floor system with a cultivation floor on which plant containers are placeable or placed, comprising: a watertight basin comprising a bottom and a perimeter; a water-permeable structure comprising at least a layer of a granular material, e.g. lava granules, filled in the basin; a permeable top fabric which covers the water-permeable structure and which forms a top side of the floor on which plant containers are placeable, optionally, a perforated film placed under the permeable top fabric, which perforated film is made of impermeable film material which is provided with distributed perforations, which film reduces the free evaporation surface for water from the water-permeable structure, a watering installation which is configured to supply water so that water is available for the plants in the plant containers, optionally an ebb/flood watering installation which comprises one or more irrigation lines, characterized in that the cultivation floor system further comprises a gas supply and distribution system, for example for supply of air and/or CO₂, wherein the gas supply and distribution system comprises a network of gas supply lines distinct from the irrigation lines and configured for distributing a gas across the floor, which network is provided in the basin lower than the top fabric, preferably embedded in the water-permeable structure or on the bottom of the basin, and wherein the gas supply and distribution system further comprises a gas supplying installation for supplying gas to the network so that, in use, the gas flows from the network and reaches the plant containers placed on the floor. The floor system may have one or more of the features described herein in relation to the system of first aspect of the invention and embodiments thereof.

A second aspect of the invention relates to a method for installing a sports pitch floor system comprising a sports pitch floor configured for performing a sport thereon.

In particular for sports pitches having, at least in part, a natural vegetation, such as grass, it is a known problem that the quality is difficult to maintain over time. For instance, grass pitches for soccer or the like sports, e.g. professional sports, require enormous efforts for maintenance. Most prominently, grass pitches in sizable stadiums suffer from extensive damage due to use as well as due to poor conditions for growth of the grass, e.g. the pitch being in the shade too much due to the structure of the stadium. It is known to improve the quality of the grass by providing extra light during the time between matches, e.g. by mobile lighting units that are temporarily placed on the pitch. Still, it is common practice for such grass pitches to be replaced in their entirety several times per year, with new, relatively thick, grass sods making up the new pitch floor. This remedy is labour intensive and expensive.

The second aspect of the invention is aimed at providing an improved sports pitch floor system.

The second aspect of the invention aims to provide a sports pitch floor system having an enhanced capability to resist intense use of the sports pitch floor, e.g. in view of the desire to reduce the need for replacement of the sports pitch as a remedy against damage.

The second aspect of the invention provides for a method for installing a sports pitch floor system comprising a sports pitch floor configured for performing a sport thereon, e.g. the sports pitch floor having a natural vegetation, e.g. grass, which method comprises:

- providing a watertight basin having a bottom and a perimeter with a top edge;

- placing one or more irrigation lines in the basin, which irrigation lines have a multitude of openings along their length for passage of water, possibly also of a gas, e.g. air and/or C02, through said openings,

- connecting a water supply and discharge system including a water pump to the one or more irrigation lines;

- filling into the basin one or more layers of loose granular material, e.g. lava granules;

- compacting the one or more layers of loose granular material so as to provide permeable granular material structure in the basin, wherein the one or more irrigation lines are covered by the granular material structure,

- providing a substantially horizontal top surface of the compacted permeable granular material at a level at or, preferably, below the top edge of the perimeter of the watertight basin,

- covering the top surface of the compacted permeable granular material by a water- permeable fabric, e.g. a (woven) cloth or a mat,

- installing a sports pitch floor on top of the water-permeable fabric, wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is flooded with water and the water level is above the water-permeable fabric, which water level is maintained for a flood period so that water is present in, e.g. absorbed by, the sports pitch floor, e.g. at least in part by the natural vegetation, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is relieved from the water after the flood period. The method includes the installation of a watertight basin having a bottom and a periphery with a top edge.

In an embodiment, a single watertight basin extends below the entirety of the sports field, e.g. below a soccer or football pitch. In another embodiment, multiple watertight basins are arranged below a single sports field, each being covered by a distinct zone of the sports field. In yet another embodiment, one or more watertight basins are located only at one or more selected zones of the sports fields, e.g. merely the goal areas of a soccer or football pitch, with one or more other zones of the sports field not being provided with a floor and watering system as described herein.

In an embodiment, the periphery of a watertight basin extends about a basin having a surface of at least 300 m2, e.g. at least 1000 m2, e.g. at least 5000 m2.

In an embodiment, the sports field has one watertight basin of which the periphery extends about the contour of the entire sports field, e.g. about the soccer pitch.

In the basin, one or more irrigation lines are placed which comprise multiple openings distributed along the length thereof which make it possible for water to flow from the one or more irrigation lines for supply of water to the pitch or back into the lines for discharge of water.

In an embodiment, the bottom of the basin is formed on a soil bed, wherein a gulley is made at the designated location of an irrigation line. An impervious ground sheet, e.g. of plastic, is placed over the bed, also covering the gulley. The bed may be sloped towards the gulley. An irrigation line is accommodate in the gulley after the sheet has been placed.

The one or more layers of loose granular material are compacted so as to provide stable and permeable granular material structure in the basin, e.g. allowing to drive with vehicles over the structure.

The one or more irrigation lines are covered by the granular material structure, e.g. as they are placed directly on the bottom of the basin.

A substantially horizontal top surface of the compacted permeable granular material is provided at a level below the top edge of the perimeter of the watertight basin and the top surface of the compacted permeable granular material is covered by a water-permeable fabric, e.g. a (woven) cloth or a mat. This allows for a uniform contact and interaction between the sports pitch floor that is placed on top of the water-permeable fabric and water that is filled into the basin up to a level (slightly) above the fabric.

In an embodiment, underneath the water-permeable fabric, a capillary mat is arranged which has a capillary action in the horizontal direction and in the vertical direction, for example a non- woven mat made of fibrous elements, for example a compacted non-woven mat.

In an embodiment, a perforated plastic film is placed directly underneath the permeable top fabric. For example, the perforated film is made of impermeable film material which is provided with distributed perforations having an average opening of between 0.75 mm2 and 108 mm2, wherein the perforations form preferably at most 10% of the surface area.

In an embodiment, the perimeter of the basin is bounded by a ground sheet, e.g. this sheet being connected to a beam about the perimeter of the basin. For example, the top side of the beam is substantially level with the top side of the floor formed by the water-permeable top fabric.

The water supply and discharge system including a water pump connected to the one or more irrigation lines allows for controlled supply of water. This system is configured to cause a supply of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is flooded with water and the water level is above the water- permeable fabric, which water level is maintained for a flood period so that water is present in, e.g. absorbed by, the sports pitch floor, e.g. at least in part by the natural vegetation.

The water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is relieved from the water after the flood period.

The frequency and/or duration and/or water height of the flood periods may be controlled over time on the basis of one or more parameters, like the presence of natural vegetation, air temperature, pitch temperature, sunlight intensity, evaporation, wind, humidity of the air and/or pitch, the presence of nutrients in the water, the demand for nutrients, etc.

The water may be combined with nutrients aiding the growth of any natural vegetation of the sports field. The water supplied to the sports pitch may be cold, or even cooled by a water cooling device, e.g. in view of reducing the temperature of the sports field and/or in a zone above the sports field, e.g. ahead of a sports match and/or during the match, e.g. beneficial for performance of the athletes, for grip of footwear on the sports field, and/or for the general thermal situation in a stadium.

It is noted that, in embodiments, water may also be supplied from above onto the sports pitch, e.g. in view of growth of any vegetation and/or in view of (briefly) wetting the pitch ahead of a match or the like. Any surplus water coming from above will then seep through the permeable fabric and be collected in the layer(s) of granular material filled in the basin, from which it can (when desired) be discharged via the irrigation lines. Of course, this can also apply to the situation of (heavy) rain when the pitch is outdoors.

Wetting the pitch, e.g. ahead of a match, can also be done using the floor system, e.g. avoiding the need to spray from above. This, e.g. may allow for wetting closer to the actual start of the match than with spraying and/or reduce the water consumption.

The permeable fabric, e.g. cloth or mat, provides for a separation between the water- permeable structure in the basin and the sports pitch floor. The water-permeable cloth or mat prevents the sports pitch floor, e.g. soil or clay, from entering in the permeable granular material structure. The latter, for example, could negatively influence the uniformity of supply of water to the sports pitch floor and/or induce undesirable growth of organisms in the granular structure.

The second aspect of the invention allows for a controlled and uniform water supply to the sports pitch floor, e.g. which allows for a controlled and uniform degree of growth of grass of the sports pitch floor. Having a high control of control of the uniform water supply to the sports pitch floor results in a higher resilience of the sports pitch floor to damages. For example, it allows for stronger grass or clay of the sports pitch floor. For example, it allows for the grass to quickly regrow after a sport has been performed on it and/or it allows for grass with stronger roots.

The second aspect of the invention is based on the insight that a combination of an ebb/flood system with a granular material filled watertight basin which is separated from the sports pitch floor by a water-permeable fabric allows for a uniform and controlled water supply to the sports pitch floor. It is known that a sports pitch floor with a suboptimal humidity is easily damaged, e.g. a clay floor may easily crack. The invention allows for optimal conditions of the sports pitch floor to perform sports and for increasing the rate of recovery of the sports pitch floor afterwards.

During installation of the sports pitch floor system, it is considered advantageous if steps of supplying water and adjusting the effective emerging flow of water are repeated one or more times until a desired uniform emerging flow of water from the one or more irrigation lines is achieved, before providing the water-permeable structure in the basin. The effective emerging flow of water may be influenced by the number and size of the openings in the irrigation lines.

In embodiments, the step of installing the sports pitch floor on top of the water-permeable fabric comprises providing one or more layers of soil, e.g. cultivation soil, e.g. wherein grass is planted in the soil and/or natural grass sods are placed on the soil. For example, the method comprises providing a combination of natural grass and artificial grass on the soil.

In embodiments of the method, the step of providing the sports pitch floor comprises providing one or more layers of soil, e.g. cultivation soil, on top of the water-permeable fabric, e.g. wherein the soil is used for the cultivation of natural grass.

In embodiments, the method comprises providing a combination of natural grass and artificial grass, wherein the combination of natural grass and artificial grass is configured for performing a sport thereon.

In many sports, e.g. American football or soccer, the sports pitch floor comprises soil and grass which are sensitive to damage. For example, the shoes used by athletes often comprise spikes for grip. These spikes may damage the sports pitch floor. The invention allows the sports pitch floor to be more resilient and recover faster. As a result a sports pitch floor of the sports pitch floor system comprising grass and/or artificial turf has to be replaced less often as compared to a traditional sports pitch floor.

In an embodiment, the sports pitch floor is composed of artificial turf, e.g. for field hockey.

The floor then allows for effective cooling of the floor, e.g. in summer. The floor may also be used for efficient wetting of the artificial turf, e.g. ahead of a match and/or during an interval of a match, e.g. using less water than with current spraying approaches.

In embodiments of the method, the step of providing the sports pitch floor comprises providing a clay layer configured for performing a sport thereon, e.g. for performing tennis thereon. Sports pitch floor comprising clay are sensitive to the amount of water supplied thereon. Too much water and the clay may become too wet and too little water and the clay may become too dry. Optimal water conditions are important for a clay sports pitch floor. The invention allows uniform control of a water supply to the sports pitch floor. This allows the clay sports pitch floor to have optimal water conditions.

In an embodiment of the method, the method further comprises the use of a gas supply, e.g. a pump, e.g. an air pump, connected to the one or more irrigation lines or, as preferred, to one or more distinct gas distribution lines arranged in the basin, which gas supply is configured for pumping a gas through the one or more lines to the basin, the gas reaching the sports pitch floor. The gas may be heated or cooled which allows for heating or cooling the sports pitch floor. Controlling the temperature of the sports pitch floor by means of a gas in addition to controlling the water supply of the sports pitch floor further increases the resilience of the sports pitch floor.

In embodiments, the sports pitch floor system is provided with a gas supply and distribution system as discussed herein with reference to the first aspect of the invention.

In embodiments, e.g. in embodiments wherein the sports pitch floor comprises natural grass, the gas may be CO2 or air with increased which improves the growth rate of the grass. This embodiment allows for control of the growth of grass by controlling the temperature, CO2 supply and water supply.

In embodiments, the floor system further comprises a gas supply and distribution system, for example for supply of air and/or CO2, wherein the gas supply and distribution system comprises a network of gas supply lines distinct from the irrigation lines and configured for distributing a gas across the floor, which network is provided in the basin below the fabric, preferably embedded in the water-permeable structure or on the bottom of the basin, wherein the gas supply and distribution system further comprises a gas supplying installation for supplying gas to the network so that, in use, the gas flows from the network reaches the sports pitch floor.

For example, the network for distributing gas is provided at least 5 cm below the fabric.

For example, the network for distributing gas comprises one or more perforated gas distribution lines having along the length thereof perforations for emitting the gas, e.g. with an inlet connected to a main gas pipe and with a closed end, e.g. multiple perforated gas distribution lines extending parallel to one another from a common main gas pipe, e.g. perpendicular to the main gas pipe.

For example, there are multiple parallel irrigation lines and one or more main gas pipes extend parallel to the irrigation lines, e.g. each main gas pipe centred between a pair of adjacent irrigation lines, and wherein perforated gas distribution lines branch off from each main gas pipe, e.g. in opposite directions, e.g. perpendicular to the main gas pipe.

For example, the network comprises a main gas pipe, e.g. which extends parallel to the irrigation lines, e.g. centred between a pair of irrigation lines, wherein perforated gas distribution lines branch off from the main gas pipe in opposite directions, e.g. perpendicular to the main gas pipe.

For example, the network comprises a main gas pipe, e.g. which extends parallel to the irrigation lines, e.g. centered between a pair of irrigation lines, the main gas pipe having a length of at least 25 meters, and wherein perforated gas distribution lines branch off from the main gas pipe in opposite directions, e.g. perpendicular to the main gas pipe, each perforated gas distribution line having a blind end and a length of between 3 and 5 meters.

In an embodiment, a water storage is provided as part of the water supply and discharge system, which system is configured to alternately draw water from the water storage for supply thereof to the one or more irrigation lines and to discharge water from the basin via the one or more irrigation lines to the water storage. This allows for more economic use of water as no or little new water has to be supplied to the system each time water is supplied to the sports pitch floor. Water that is supplied to the sports pitch floor, either by the system or as rain, may be stored in the water storage for later use after draining the water from the sports pitch floor by the sports pitch floor system.

In an embodiment, a water storage is present in the ground under the sports pitch floor.

In an embodiment of the method, the basin has a bottom profile which is produced in a bed, for example in a bed of sand, comprising a gulley in the bottom profile in which an irrigation line is provided and a bottom surface on one or both sides of the channel, preferably a bottom surface sloping towards the channel, wherein the bed is covered by a watertight membrane, after which the irrigation line is placed in the channel, wherein, for example, the gulley is formed such that it has a cross section which corresponds to the cross section of at least the bottom portion of the irrigation line to be accommodated therein.

Preferably, the gulley is formed such that it has a cross section which corresponds to the cross section of at least the bottom portion of the irrigation line to be accommodated therein. Thus, a zone where stagnant water could collect next to the bottom part of the irrigation line is avoided. In particular, this measure is advantageous if the line is only provided with openings in a top portion, above the channel.

In an embodiment, the irrigation line is a plastic line with a smooth wall, preferably made of PVC. Preferably, no corrugated lines are used as irrigation lines, but rather lines which have a closed and smooth, non-corrugated peripheral wall. For example PVC lines with a smooth wall. It has been found that, due to the shape of a corrugated wall, these corrugated lines contribute to a non-uniform emerging flow of the water. In this respect, the lines with a smooth wall perform better and they are also available in strong designs, in which openings can readily be made without being too disadvantageous for the mechanical load-bearing capacity of the line. In a practical embodiment of the method, the irrigation lines placed in the basin, for example smooth-walled PVC lines, are provided with several openings along their length, for example at regular intervals, in an initial processing step.

In an embodiment, the irrigation line is accommodated in a channel, so that a top portion of the line is exposed, and wherein the one or more openings are formed or enlarged in the exposed top portion of the line. If desired, a small number of openings may be provided in the bottom portion in order to avoid accumulation of water at the underside of the line, and possible floating up of the drained line. This is an effective approach, for example, if only a top cloth is used as water-permeable structure.

In embodiments, the method comprises the steps of - while the one or more irrigation lines have been placed in the basin and a pump is connected thereto - supplying water to the one or more irrigation lines by means of the pump and monitoring the emerging flow of the water from the one or more irrigation lines in order to check whether the emerging flow is uniform across the one or more irrigation lines in the basin, and - if deviations in the emerging flow are observed - adjusting the effective emerging flow by providing the one or more irrigation lines, in situ, with one or more additional openings or increasing the dimensions of one or more openings at a location where the emerging flow is considered to be too small and/or closing one or more openings of the irrigation lines or reducing the dimensions of one or more openings at a location where the emerging flow is considered to be too large. This embodiment is based on the insight that it is found that the water level above the top does not rise in a uniform manner everywhere, as a result of which the sports pitch floor at some locations has a different water regime than at different locations on the sports pitch floor. This embodiment is furthermore based on the insight that the emerging flow of water from the one or more irrigation lines affects the uniformity with which the water rises (viewed across the surface of the sports pitch floor), despite the presence of a water-permeable structure in the basin.

This embodiment makes it possible to improve the uniformity of the rise of the water level, viewed across the floor, by adjusting “in situ” the effective emerging flow of the one or more irrigation lines. This is preferably carried out by providing the one or more irrigation lines with one or more additional openings or increasing the dimensions of one or more openings at a location where the emerging flow is thought to be too small.

In practice, the monitoring can take the form of a visual check by a monitoring individual, but it is also conceivable to provide a measuring system. For example, a system with one or more cameras could be provided which record the emerging flow and said images are then looked at by a monitoring individual. If desired, it is also possible to provide software which analyses the camera images in order to assess the emerging flow of water and determine the locations at which the emerging flow is too small and/or too large.

In an embodiment, the basin bottom is provided with a watertight plastic film, which preferably also extends underneath the one or more irrigation lines.

The second aspect of the invention further relates to a sports pitch floor system installed using the method according to the invention.

The second aspect of the invention further relates to a sports pitch floor system with a sports pitch floor configured for performing a sport thereon, which sports pitch floor system comprises:

- a watertight basin having a bottom and a perimeter with a top edge;

- one or more irrigation lines placed in the basin, which irrigation lines have a multitude of openings along their length for passage of water, possibly also of a gas, e.g. air and/or C02, through said openings,

- a water supply and discharge system including a water pump connected to the one or more irrigation lines;

- one or more layers of loose granular material, e.g. lava granules, filled in the basin; said one or more layers of loose granular material being compacted so as to provide permeable granular material structure in the basin, wherein the one or more irrigation lines are covered by the granular material structure,

- the compacted permeable granular material having a substantially horizontal top surface at a level at or below the top edge of the perimeter of the watertight basin,

- a water-permeable fabric, e.g. a (woven) cloth or a mat, covering the top surface of the compacted permeable granular material,

- a sports pitch floor on top of the water-permeable fabric, wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is flooded with water and the water level is above the water-permeable fabric, which water level is maintained for a flood period so that water is present in, e.g. absorbed by, the sports pitch floor, e.g. at least in part by the natural vegetation, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is relieved from the water after the flood period.

The sports pitch floor system of the second aspect of the invention allows for a beneficial water supply to the sports pitch floor. When water is supplied, the water level in the basin rises, in practice until the water rises up through the permeable fabric everywhere and uniformly. Thereby the bottom part of the sports pitch floor is penetrated by water.

The combination of an ebb/flood system for providing water to irrigation lines provided in a water-permeable granular material structure which is separated from the sports pitch floor by a water-permeable fabric provides for uniform and controlled water supply to the sports pitch floor. It is well-known that a sports pitch floor with a suboptimal humidity is easily damaged, e.g. a clay floor may easily crack.

In an embodiment, the sports pitch floor comprises one or more layers of soil, e.g. cultivation soil, on top of the water-permeable fabric, e.g. wherein grass is planted in the soil and/or natural grass sods are placed on the soil. For example, the sports pitch floor comprises a combination of natural grass and artificial grass.

In an embodiment, the sports pitch floor comprises a clay layer configured for performing a sport thereon, e.g. for performing tennis thereon. In an embodiment, the sports pitch floor system further comprises a gas pump, connected to the one or more irrigation lines, which gas pump is configured for pumping a gas, e.g. a heated or cooled gas, through the one or more irrigation lines towards the sports pitch floor.

In an embodiment, the sport pitch floor system comprises a gas supply and distribution system as discussed herein with reference to the first aspect of the invention.

In an embodiment, the sports pitch floor system further comprises a water storage, wherein the water supply and discharge system is configured to selectively draw water from the water storage for supply to the one or more irrigation lines and for discharge of water via the one or more irrigation lines to the water storage.

In an embodiment, the basin has a bottom profile comprising a gulley in the bottom profile in which an irrigation line is provided and a bottom surface on one or both sides of the gulley, preferably a bottom surface sloping towards the gulley, wherein the profile is covered by a watertight membrane, wherein the irrigation line is placed in the channel, wherein, for example, the gulley is formed such that it has a cross section which corresponds to the cross section of at least the bottom portion of the irrigation line to be accommodated therein.

For example, the irrigation line is a plastic line with a smooth wall, preferably made of PVC.

For example, the irrigation line is accommodated in a gulley, so that a top portion of the line is exposed, and wherein the one or more openings are formed in the exposed top portion of the line.

The second aspect of the invention also relates to use of the sports pitch floor system as described herein, e.g. for irrigating or draining the sports pitch floor.

The second aspect of the invention also relates to use of the sports pitch floor system as described herein for the cultivation of grass that is grown on the sports pitch floor.

In particular, the second aspect of the invention is related to use of a sports pitch floor system according to the invention for irrigating or draining a sports pitch floor. The sports pitch floor system of the invention is configured for use of irrigation the sports pitch floor with water and for draining excess water from the sports pitch floor. The use of the sports pitch floor system extends to using the sports pitch floor system for precisely controlling the amount of water, e.g. the water level, in the sports pitch floor system. The ebb/flood system allows use of the system for controlling, e.g. periodically controlling, the amount of water present. The amount of water may be controlled based on the use of the sports pitch floor system as a sports pitch floor for sports.

The second aspect of the invention further relates to the use of a sports pitch floor system of the invention comprising grass in the sports pitch floor for the cultivation of grass grown on the sports pitch floor. Use of the sports pitch floor system allows for control over the growth conditions of the grass. For example, the system may be used to make the roots of the grass longer by gradually reducing the water level in the sports pitch floor system over time. The grass roots will grow longer in order to follow the reducing water level. A result of this is grass with longer roots which is stronger and more resilient to damage.

The second aspect of the invention also relates to the use of a sports pitch floor system as described herein, e.g. the sports pitch floor being composed of or comprising artificial turf, wherein the floor is wetted ahead of the use of the floor, e.g. ahead of a match and/or during an interval of the match, by means of supply of water to the basin. For example, nowadays artificial turf sports pitch floors are wetted ahead of a match by spraying water over the pitch. This leads to undue consumption of water, especially in warm regions, takes significant efforts, and blocks players and/officials from access to the pitch. Wetting the artificial turf from below by appropriate supply of water to the basin allows to improve these issues. The basin may then be emptied, fully or partly, e.g. the remaining water continuing to act as a coolant for the pitch and possibly an air zone above the pitch.

The second aspect of the invention also relates to a method for growing and harvesting natural grass sods, e.g. for use on a sports pitch, wherein the grass is grown in a bed of soil so that roots develop within the bed and the grass grows, the grown grass being harvested as grass sods, wherein the bed of soil is installed on a floor system as described herein. The floor system allows, in various embodiments thereof, for accurate control of the watering and of the micro-climate in which the sods are grown, as well as the option of nutrients being mixed into the water and/or controlled gas supply.

The second aspect of the invention also relates to a method for growing and harvesting natural grass sods, e.g. for use on a sports pitch, wherein the grass is grown in a bed of soil so that roots develop within the bed and the grass grows, the grown grass being harvested as grass sods, wherein the bed of soil is installed on a floor system, wherein the floor system comprises:

- a watertight basin having a bottom and a perimeter with a top edge; - one or more irrigation lines placed in the basin, which irrigation lines have a multitude of openings along their length for passage of water, possibly also of a gas, e.g. air and/or C02, through said openings,

- a water-permeable fabric, e.g. a cloth, e.g. a woven cloth, or a mat, covering the top surface of the compacted permeable granular material, wherein the bed of soil is installed on top of the water-permeable fabric, wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is flooded with water and the water level is above the water-permeable fabric, which water level is maintained for a flood period so that water is absorbed by the bed and the grass, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is relieved from the water after the flood period, wherein the grown grass is harvested as grass sods.

A third aspect of the invention relates to the field of growing a harvestable crop, e.g. soil- grown crops. The third aspect of the invention provides for an installation or facility and a method for growing and harvesting a soil-grown crop, wherein the crop is planted in a bed of soil and/or growing medium so that roots of the crop develop within the bed and the crop grows. The grown crop is harvested. Depending on the type of crop the roots are removed from the bed, e.g. of soil, upon harvesting or remain in the bed.

When growing a crop, whether outdoors or in a greenhouse or the like, the control of the conditions governing the growth is crucial. Equally, the efficient use of resources, e.g. like water and energy is of importance. Further, environmental aspects are of relevance, e.g. the desire to avoid draining nutrient rich water used in the growth process into nearby waterways.

The third aspect of the invention is aimed at providing an improved installation and method for growing and harvesting a crop, wherein the crop is planted in a bed of soil and/or growing medium so that roots of the crop develop within the bed and the crop grows, the grown crop being harvested.

The third aspect of the invention provides for an installation or facility for growing and harvesting a crop, wherein the crop is planted in a bed of soil and/or of growing medium, so that roots of the crop develop within the bed and the crop grows, the grown crop being harvested, wherein the installation comprises a bed of soil and/or growing medium that is installed on a floor system, wherein the floor system comprises:

- a watertight basin having a bottom and a perimeter with a top edge;

- the compacted permeable granular material having a substantially horizontal top surface at a level at or, preferably, below the top edge of the perimeter of the watertight basin,

- a water-permeable fabric, e.g. a (woven) cloth, e.g. a woven cloth, or a mat, covering the top surface of the compacted permeable granular material, wherein the bed of soil and/or of growing medium is installed on top of the water-permeable fabric, wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is flooded with water and the water level is above the water-permeable fabric, which water level is maintained for a flood period so that water is absorbed by the bed and the crop, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is relieved from the water after the flood period.

The third aspect of the invention further relates to a method for growing and harvesting a crop, wherein the crop is planted in a bed of soil and/or of growing medium so that roots of the crop develop within the bed and the crop grows, the grown crop being harvested, wherein the bed of soil and/or growing medium is installed on a floor system, wherein the floor system comprises:

- a watertight basin having a bottom and a perimeter with a top edge;

- a water-permeable fabric, e.g. a cloth, e.g. a woven cloth, or a mat, covering the top surface of the compacted permeable granular material, wherein the bed of soil and/or of growing medium is installed on top of the water-permeable fabric, wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is flooded with water and the water level is above the water-permeable fabric, which water level is maintained for a flood period so that water is absorbed by the bed and the crop, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is relieved from the water after the flood period.

In embodiments, as preferred, - after harvesting the crop - the bed remains installed on the floor system and a new crop is planted for growing and harvesting, e.g. the bed remaining installed at least one year, e.g. several years, before being renewed. The bed may be composed entirely or primarily of soil. In other embodiments, the crop grows in a soilless approach in a bed that is entirely or primarily composed of a growing medium. Examples of growing media are perlite, rockwool, expanded clay, vermiculite, etc. Combinations are also envisaged.

The third aspect of the invention proposes the installation of a watertight basin having a bottom and a periphery with a top edge.

In an embodiment, a single watertight basin extends below the entirety of a continuous bed, which can be, for example, at least 100 m2, e.g. at least 1000 m2, e.g. over 5000 m2, in size. In another embodiment, multiple watertight basins are arranged below a single continuous bed of soil, each being covered by a distinct zone of the bed.

In an embodiment, the periphery of a watertight basin extends about a basin having a surface of at least 100 m2, e.g. at least 1000 m2, e.g. at least 5000 m2.

In the basin, one or more irrigation lines are placed which each comprise multiple openings distributed along the length thereof, which make it possible for water to flow from the one or more irrigation lines for supply of water to the bed or back into the lines for discharge of water.

In an embodiment, the bottom of the basin is formed in the ground, e.g. wherein a gulley is made in the ground at the designated location of an irrigation line. An impervious ground sheet, e.g. of plastic, is placed, also covering the gulley. The bed may be sloped towards the gulley. An irrigation line is accommodate in the gulley after the sheet has been placed.

One or more layers of loose granular material, e.g. of lava granules, are compacted so as to provide stable and permeable granular material structure in the basin.

A substantially horizontal top surface of the compacted permeable granular material is provided at a level at or below the top edge of the perimeter of the watertight basin and the top surface of the compacted permeable granular material is covered by a water-permeable fabric, e.g. a (woven) cloth or a mat. The bed of soil and/or growing medium may have a thickness adapted to the crop, e.g. of at least 10, e.g. at least 15 cm.

When water is supplied to the basin by the irrigation lines, the water level in the basin rises, in practice until the water rises up through the permeable fabric everywhere and uniformly. Thereby the bottom part of the bed of soil is penetrated by the rising water.

The combination of an ebb/flood system for providing water to irrigation lines provided in a water-permeable granular material structure which is separated from the bed by a water- permeable fabric provides for uniform and controlled water supply to the bed.

The frequency and/or duration and/or water height of the flood periods may be controlled over time on the basis of one or more parameters, like the crop, the actual growth phase of the crop, the actual size of the crop, air temperature, soil bed temperature, sunlight intensity, evaporation, wind, humidity of the air and/or soil, the presence of nutrients in the water, the demand for nutrients, etc.

In an embodiment, the perimeter of the basin is bounded by the ground sheet, e.g. this sheet being connected to a beam about the perimeter of the basin. For example, the top side of the beam is substantially level with the top side of the floor formed by the water-permeable top fabric.

The water supply and discharge system including a water pump connected to the one or more irrigation lines allows for controlled supply of water. This system is configured to cause a supply of water via the one or more irrigation lines so that the water-permeable granular material structure in the basin is flooded with water and the water level is above the water- permeable fabric, which water level is maintained for a flood period so that water is absorbed by the bed of soil, e.g. at least in part by the crop.

The water may be combined with nutrients aiding the growth of the crop, e.g. the nutrients being supplied by a nutrient pump from a nutrient storage container.

The water may be combined with a sterilizing agent or the like, e.g. when sterilization is performed between crops.

The water supplied to the basin via the irrigation lines may be cold, or even cooled by a water cooling device, e.g. in view of reducing the temperature of the bed and/or in an air zone above bed, e.g. in a zone where the crop grows. For example, the bed and the air zone where the crop grows can be kept relatively cold compared to higher air layers by suitable supply of water. This is, for example, of benefit in a greenhouse, where temperature may rise in summer. The inventive floor then may be used to cool just the air zone where the crop grows, whilst allowing for higher temperature above said zone.

It is noted that, in embodiments, water may additionally be supplied from above onto the bed and/or crop by a further watering system or rain. Any surplus water coming from above will then seep through the bed and the permeable fabric and be collected in the layer(s) of granular material filled in the basin, from which it can (when desired) be discharged via the irrigation lines. Of course, this can also apply to the situation of absorbing (heavy) rain when the installation is outdoors.

The permeable fabric, e.g. cloth, e.g. a woven cloth, or mat, provides for a separation between the water-permeable structure in the basin and the bed. The water-permeable cloth or mat prevents the bed soil material, as well as the roots, e.g. the bulk of the roots, from entering into the permeable granular material structure. The latter, for example, could negatively influence the uniformity of supply of water to the bed or the crop and/or induce undesirable growth of organisms in the granular structure. The third aspect of the invention allows for a controlled and uniform water supply to the bed of soil and thus to the crop, e.g. which allows for a controlled and uniform degree of growth of the crop. As explained herein, the third aspect of the invention also allows for a controlled micro-climate in which the crop grows.

The third aspect of the invention is based on the insight that a combination of an ebb/flood system with a granular material filled watertight basin which is separated from the bed of soil and/or growing medium in which the roots of the crop grow by a water-permeable fabric allows for a uniform and controlled water supply to the bed. The invention allows for enhanced or optimal control conditions to grow a crop.

During installation of the floor system, it is considered advantageous if steps of supplying water and adjusting the effective emerging flow of water are repeated one or more times until a desired uniform emerging flow of water from the one or more irrigation lines is achieved, before providing the water-permeable structure in the basin. The effective emerging flow of water may be influenced by the number and size of the openings in the irrigation lines.

In an embodiment, a gas supply, e.g. comprising a gas pump, e.g. a compressor or blower, is provided, connected to the one or more irrigation lines or to dedicated gas distribution lines distinct from the irrigation lines. The gas supply is configured for pumping a gas, e.g. air, through the one or more lines towards the basin and then through the bed of soil. The gas may be heated or cooled, which allows for heating or cooling the bed and possibly an air zone directly above the bed where the crop grows.

Controlling the temperature of the bed by controlled supply of a gas via the basin, e.g. air, in addition to controlling the water supply of the bed further increases the control of conditions for growth of the crop. In embodiments, the gas may be CO2, which improves the growth rate of the crop. This embodiment allows for control of the growth by controlling the temperature, CO2 supply and water supply.

In an embodiment, a gas supply and distribution system is provided, for example for supply of air and/or C02, e.g. as described herein with reference to the first aspect of the invention, wherein the gas supply and distribution system comprises a network of gas supply lines distinct from the irrigation lines and configured for distributing a gas across the floor, which network is provided in the basin embedded in the water-permeable structure or on the bottom of the basin, wherein the gas supply and distribution system further comprises a gas supply installation for supplying gas to the network and in to the basin to reach the bed. For example, the network for distributing gas is provided at least 5 cm below the fabric.

For example, one or more main gas pipes extend parallel to the irrigation lines, e.g. each main gas pipe centred between a pair of adjacent irrigation lines, wherein perforated gas distribution lines branch off from each main gas pipe, e.g. in opposite directions, e.g. perpendicular to the main gas pipe.

For example, the network comprises a main gas pipe, e.g. which extends parallel to the irrigation lines, e.g. centred between a pair of irrigation lines, the main gas pipe having a length of at least 25 meters, and wherein perforated gas distribution lines branch off from the main gas pipe in opposite directions, e.g. perpendicular to the main gas pipe, each perforated gas distribution line having a blind end and a length of between 3 and 5 meters.

For example, the network for distributing gas comprises perforated gas distribution lines having along the length thereof perforations for emitting the gas, e.g. with an inlet connected to a main gas pipe and with a closed end, wherein multiple perforated gas distribution lines extend, e.g. parallel to one another from a common main gas pipe, e.g. perpendicular to the main gas pipe, and wherein a flow rate adjusting device is present at the inlet of each perforated gas distribution line.

For example, the network is supported at a distance above the bottom of the basin by spacers that are placed on the bottom of the basin, e.g. prior to filling granular material in the basin.

For example, the gas supply and distribution system is adapted to heat and/or cool the gas before distributing the gas, e.g. air. In an embodiment, a water storage is provided and in operation alternately water is drawn from the water storage and supplied to the basin and water is discharged from the basin to the water storage. This allows for more economic use of water as no or little new water has to be supplied to the system each time water is supplied to the bed of soil. Water that is supplied to the bed, either by the system or as rain, may be stored in the water storage for later use after draining the water from the basin.

In an embodiment, the basin has a bottom profile comprising a gulley in the bottom profile in which an irrigation line is provided and a bottom surface on one or both sides of the channel, preferably a bottom surface sloping towards the channel, wherein the profile is covered by a watertight membrane, after which the irrigation line is placed in the gulley, wherein, for example, the gulley is formed such that it has a cross section which corresponds to the cross section of at least the bottom portion of the irrigation line to be accommodated therein.

Preferably, the gulley is formed such that it has a cross section which corresponds to the cross section of at least the bottom portion of the irrigation line to be accommodated therein. Thus, a zone where stagnant water could collect next to the bottom part of the irrigation line is avoided. In particular, this measure is advantageous if the line is only provided with openings in a top portion, above the gulley.

In an embodiment, the irrigation line is a plastic line with a smooth inner wall, preferably made of PVC. Preferably, no corrugated lines are used as irrigation lines, but rather lines which have a closed and smooth, non-corrugated peripheral wall. For example, PVC lines with a smooth wall. It has been found that, due to the shape of a corrugated wall, these corrugated lines contribute to a non-uniform emerging flow of the water. In this respect, the lines with a smooth wall perform better and they are also available in strong designs, in which openings can readily be made without being too disadvantageous for the mechanical load-bearing capacity of the line. In a practical embodiment of the method, the irrigation lines placed in the basin, for example smooth-walled PVC lines, are provided with several openings along their length, for example at regular intervals, in an initial processing step.

In an embodiment, the irrigation line is accommodated in a gulley, so that a top portion of the line is exposed, wherein the one or more openings are formed or enlarged in the exposed top portion of the line. If desired, a small number of openings may be provided in the bottom portion in order to avoid accumulation of water at the underside of the line, and possible floating up of the drained line. This is an effective approach, for example, if only a top cloth is used as water-permeable top structure. In embodiments, the method comprises the steps of - while the one or more irrigation lines have been placed in the basin and a pump is connected thereto - supplying water to the one or more irrigation lines by means of the pump and monitoring the emerging flow of the water from the one or more irrigation lines in order to check whether the emerging flow is uniform across the one or more irrigation lines in the basin, and - if deviations in the emerging flow are observed - adjusting the effective emerging flow by providing the one or more irrigation lines, in situ, with one or more additional openings or increasing the dimensions of one or more openings at a location where the emerging flow is considered to be too small and/or closing one or more openings of the irrigation lines or reducing the dimensions of one or more openings at a location where the emerging flow is considered to be too large.

This embodiment is based on the insight that it is found that the water level above the top does not rise in a uniform manner everywhere, as a result of which the bed of soil at some locations has a different water regime than at different locations. This embodiment is furthermore based on the insight that the emerging flow of water from the one or more irrigation lines affects the uniformity with which the water rises (viewed across the surface of the bed), despite the presence of a water-permeable structure in the basin.

This embodiment makes it possible to improve the uniformity of the rise of the water level, viewed across the floor, by adjusting “in situ” the effective emerging flow of the one or more irrigation lines. This is, preferably, carried out by providing the one or more irrigation lines with one or more additional openings or increasing the dimensions of one or more openings at a location where the emerging flow is thought to be too small.

In practice, the monitoring can take the form of a visual check by a monitoring individual, but it is also conceivable to provide a measuring system. For example, a system with one or more cameras could be provided which record the emerging flow and said images are then looked at by a monitoring individual. If desired, it is also possible to provide software, which analyses the camera images in order to assess the emerging flow of water and determine the locations at which the emerging flow is too small and/or too large.

In an embodiment, the installation is arranged in a greenhouse. As discussed the floor system with bed thereon can also be installed outdoors.

The third aspect of the invention, also relates to a greenhouse provided with the installation according to the third aspect of the invention.

A fourth aspect of the invention relates to a method for growing and harvesting a crop, wherein the crop is planted in a bed of soil so that roots of the crop develop within the bed and the crop grows, the grown crop being harvested, wherein the bed of soil is installed on a floor system, wherein the floor system comprises:

- a watertight basin having a bottom and a perimeter with a top edge;

- one or more irrigation lines placed in the basin,

- one or more layers of loose granular material, e.g. lava granules, filled in the basin and forming a water-permeable granular material structure in the basin,

- the compacted permeable granular material having a substantially horizontal top surface, e.g. at a level at or below the top edge of the perimeter of the watertight basin,

- a water-permeable fabric, e.g. a cloth, e.g. a woven cloth, or a mat, covering the top surface of the compacted permeable granular material, wherein the bed of soil is installed on top of the water-permeable fabric, wherein, e.g. after harvesting a grown crop, the bed of soil is subjected to a tillage operation, wherein use is made of a tillage device which comprises:

- a frame, e.g. a vertically adjustable frame, that is configured and operated so as to be moved over the bed of soil,

- rigid tillage members, e.g. rigid rotary tillage members, supported by the frame and configured and operated to perform a tillage operation on an upper layer of the soil bed;

- flexible tillage members, e.g. supported by the frame and/or by rigid tillage members, configured and operated to perform a tillage operations on a lower layer of the soil bed;

- a height sensor assembly for measuring a height of the frame and/or of the rigid tillage members relative to the water-permeable fabric; and

- a controller assembly for controlling a height of the frame and/or of the rigid tillage members relative to the water-permeable fabric, which controller assembly is connected to the height sensor assembly, wherein the controller assembly is configured and operated to adjust the height of the frame and/or of the rigid tillage members relative to the water-permeable fabric based on the measured height such that the rigid tillage members remain clear from the water-permeable fabric during the tillage operation.

In the fourth aspect of the invention the floor system may have embodiments as described herein with reference to the third aspect of the invention. The tillage device allows for tillage of the soil bed over its entirety thickness or height without risking that the water-permeable fabric becomes damaged, e.g. torn and/or cut, by the rigid tillage members. These rigid members are kept away from the fabric, which would cause a lower layer to be not subjected to tillage. However, the provision of the flexible tillage members causes the lower layer to be subjected to tillage as well. For example, this approach seeks to avoid that this lower layer becomes and/or remains a dense barrier between the upper layer of the soil bed and the lower lying granular material structure of the floor. Such a barrier would or might potentially impair the functionality of the combination of the soil bed and the floor, e.g. disturb flow of water and/or of gas, and thus would impair optimal growth of the crop.

It is noted that, for example, JPH10262415A discloses a tillage control device for a tractor in which an attempt is made to form a tillage surface cultivated by a tiller clow at a constant height to reduce an uneven surface. The tillage control device makes a cultivated surface of a constant height by the vertical movement of the cultivation device with respect to a vehicle body by detection by a laser sensor of a laser beam. The control device has several modes for tilling.

In embodiments, the rigid tillage members are rotary tillage members, e.g. rotary disc members, e.g. driven by a corresponding drive, e.g. the rotary tillage members being rotatable about a horizontal axis during operation, e.g. multiple rotary disc members arranged on a common horizontal shaft of the tillage device .

Preferably, the flexible tillage members are embodied such that they are sturdy enough to perform a tillage operation of the lower soil layer and flexible enough to not damage the fabric, e.g. because they flex (e.g. upward) when coming into contact with the fabric. The flexibility may stem from a flexible mounting of the flexible tillage members, e.g. using (air) springs, combined with flexibility of the flexible members themselves, e.g. made of plastic material, etc.

In embodiments, the flexible tillage members trail behind the rigid tillage members, e.g. in close proximity to the rigid tillage members. For example, there are flexible tillage fingers that trail behind rigid tillage members during the tillage operation. In embodiments, the flexible tillage members are passive members, in other embodiments they are associated with a corresponding drive to perform a driven tillage motion, e.g. rotating, vibrating, etc. In embodiments, the flexible tillage members are mounted on the rigid tillage members, e.g. the flexible tillage members are provided on, for example an outer edge of, the rigid rotary members. In an embodiment, the flexible tillage means may be flexible members that are provided on a lower portion of rigid tillage members, e.g. cutters and/or blades, such that the flexible members penetrate deeper into the soil bed.

In embodiments, both the rigid tillage members and the flexible tillage members are supported by the frame, either directly, e.g. each mounted directly on the frame, or indirectly, e.g. wherein the flexible members are mounted on the rigid members which are mounted on the frame. For example, the frame is adjustable in a vertical direction, with the height of the tillage members then also being adjusted along with the frame. Thus, in this embodiment, by controlling the height of the frame relative to the cultivation floor the height of the tillage members is also adjusted.

In embodiments, the frame may be supported by wheels for moving over the soil bed, e.g. wherein the frame comprises a hydraulic or other mechanical system for vertically adjusting the frame relative to the wheels. In other embodiments the frame may be attached to mounting means of a vehicle that is driven over or along the soil bed, wherein the frame may be vertically adjusted relative to the mounting means when mounted on the vehicle.

In embodiments, the height sensor is a laser sensor, for example which measures a height of the frame based on measurements of a laser beam, e.g. which is at a fixed height relative to the water-permeable fabric.

The height sensor may be mounted on the frame and measure the height of the frame relative to a point which has a known height relative to the water-permeable fabric. For example, the height sensor is a laser beam sensor which measures a height of a laser beam which is at a fixed height above the floor. The height sensor may also be provided away from the frame, e.g. to a side of the floor, and measure the height of the frame relative to its own height.

In embodiments, the flexible tillage members are configured and operated to contact the water-permeable fabric during operation of the tillage device without damaging the fabric.

The fourth aspect also relates to a tillage device which comprises:

- a frame, e.g. a vertically adjustable frame, that is configured and operated so as to be moved over the bed of soil, - rigid tillage members, e.g. rigid rotary tillage members, supported by the frame and configured to perform a tillage operation on an upper layer of the soil bed;

- flexible tillage members, e.g. supported by the frame and/or by rigid tillage members, configured to perform a tillage operation on a lower layer of the soil bed;

- a height sensor assembly for measuring a height of the frame and/or of the rigid tillage members relative to a reference level, e.g. a water-permeable fabric underneath the soil bed; and

- a controller assembly for controlling a height of the frame and/or of the rigid tillage members relative to the reference level, which controller assembly is connected to the height sensor assembly, wherein the controller assembly is configured and operated to adjust the height of the frame and/or of the rigid tillage members relative to the reference level based on the measured height such that the rigid tillage members remain clear from the reference level during the tillage operation.

The fourth aspect of the invention also relates to the use of such a tillage device.

The invention also relates to a greenhouse provided with a floor system according to the invention and/or wherein use is made of a method according to the invention.

The various aspects of the invention will be explained below with reference to the drawing, in which:

- Fig. 1 diagrammatically shows a cultivation floor system to illustrate the first aspect of the invention;

- Fig. 2 shows a cross section of a part of the figure 1 ;

- Fig. 3 diagrammatically shows a sports pitch floor system to illustrate the second aspect of the invention;

- Fig. 4 shows a cross section of a part of the sports pitch floor system of figure 3;

- Fig. 5 diagrammatically shows an installation to illustrate the third aspect of the invention; and

- Fig. 6 shows a cross section of a part of the third aspect of the installation,

- Fig. 7 illustrates the fourth aspect of the invention.

Figure 1 diagrammatically shows a cultivation floor system 1 on which plant containers are placed comprising a watertight basin 4. The basin 4 has a bottom profile 12 which is produced in a bed, for example in a bed of sand. Several U-shaped channels 14 are provided in the bottom profile 12 and extend substantially parallel to each other. Although two channels 14 are shown in Figure 1, the bottom profile 12 may comprise significantly more channels 14. On either side of each channel 14, the bottom profile 12 comprises a bottom surface 16 which runs off towards said channel 14. After the bottom profile 12 has been formed, the bed of the bottom profile 12 may be covered with a watertight membrane 12a.

An irrigation line 7 is provided in each channel 14. The irrigation lines 7, preferably, have a closed and smooth, non-corrugated peripheral wall. The irrigation lines 7 are, for example, formed by plastic pipes with smooth walls, such as PVC pipes. The outer diameter of the irrigation lines 7 may correspond to the curvature of the bottom of the U-shaped channels 14, in other words the channels 14 are produced with a cross section which corresponds to the cross section of at least the bottom portion of the irrigation line 7 to be accommodated therein.

When installing the irrigation lines 7, each irrigation line 7 may already have been provided with several lateral outflow openings 8, which are a distance apart in the longitudinal direction of this irrigation line 7, for example equidistant from each other. Instead, it is also possible for one or more irrigation lines 7 to be configured such that they are initially closed, that is to say have a closed pipe wall, in which case the outflow openings 8 are made after these irrigation lines 7 have been accommodated in the channels 14 and preferably in the exposed top portion of these irrigation lines 7.

The outflow openings 8 can be made in the irrigation lines 7 in different ways. The outflow openings 8 are, for example, made using a tool which is provided with a base comprising guide means, for example wheels, which are configured to engage with an irrigation line 7. The tool can be placed on an irrigation line 7 and moved along the irrigation line 7. At a location where an outflow opening 8 is desired, the tool may perform an operation on the irrigation line 7 to form the outflow opening 8, for example by drilling, milling, sawing, burning, cutting, or punching.

The irrigation lines 7 are part of the watering installation which, in this embodiment, further comprises a valve assembly 21. The irrigation lines 7 are connected to the valve assembly 21 via a supply/discharge line 20. The valve assembly 21 is furthermore connected to a water storage 11 and a water pump 10. A water-permeable structure 5 is arranged in the basin 4. The water-permeable structure 5 preferably comprises one or more layers of granular material, but may also (or in combination with the latter) comprise one or more water-permeable mats.

In this case, the irrigation lines 7 are covered by the water-permeable structure 5.

The water-permeable structure 5 furthermore comprises a permeable and horizontal top layer which forms a cultivation floor 2. The top layer comprises a top fabric 17, such as a woven top fabric, in which pores are present between the yarns of the fabric.

The top fabric 17 is permeable, having a relatively high porosity and small pores. Preferably, the top fabric is woven, for example from suitable synthetic yarn, and the pores between the yarns of the top fabric 17 are relatively small. The top fabric is preferably UV-resistant and also wear-resistant, for example suitable to be driven over by lightweight vehicles.

The top fabric 17 in figure 2 is situated directly on top of a perforated film 40 containing perforations 41, so that the perforated film is present between the permeable top fabric 17 on the one hand and the water-retaining layer 5 on the other hand, which perforated film is made of impermeable film material which has been provided with distributed perforations in such a manner that the film reduces the free evaporation surface of water from the water- retaining layer 5 preferably by at least 50%, more preferably by at least 90%.

Preferably, the cultivation floor 2 is sufficiently stable to drive across it with a vehicle.

Plant containers 6 containing plants to be grown or the like are placed on the cultivation floor 2. The plant containers 6 are, for example, partly open on the underside and/or are configured to be completely or partly water-permeable.

The water storage 11, the water pump 10, the valve assembly 21, the supply/discharge line 9 and the irrigation lines 7 together form the watering installation, e.g. an ebb/flood watering installation which is configured to alternately cause a supply of water to the cultivation floor 2 and a discharge of water from the cultivation floor 2, preferably with a highest water level above the top fabric.

The cultivation floor system 1 further comprises a gas supply and distribution system 18, 19 comprising a gas supply installation 18 and a network. In this embodiment, the network comprises a main gas pipe 23 and multiple perforated distribution lines, e.g. pipes and/or hoses 19, branching from the common main gas pipe 23. Each line 19 has along the length thereof perforations for emitting the gas, e.g. with an inlet connected to a main gas pipe and with a closed end.

In an embodiment, a flow rate adjusting device is present at the inlet of each perforated gas distribution line 19

In this embodiment, the gas supply installation 18 is connected to the main gas pipe 23 which is embedded in the basin 4 between two channels 14.

The main gas pipe 23 is connected to the perforated pipes and/or hoses 19 which are provided perpendicularly to the irrigation lines 7.

In operation, gas flows from the gas supply installation 18 through the main gas pipe 23 towards the perforated pipes and/or hoses 19. The gas then flows out of the perforated pipes and/or hoses into the water-permeable structure 5 and then through the perforations in the film 40 and through the fabric. The gas rises uniformly towards the cultivation floor 2 and to the plant containers 6.

In embodiments, the gas supply installation 18 is configured to heat and/or cool the gas before supplying it to the network for gas distribution. This, possibly in combination with a variable frequency and/o flow rate of gas flow, allows for controlling a climate around the plant containers 6.

With the cultivation floor system 1 a uniform irrigation and a uniform supply of gas to the plant containers 6 is achieved.

Figure 2 diagrammatically shows a cross section, not to scale, of the structure of a cultivation floor system 1.

Figure 2 shows a cross section showing a perforated pipe 19 supported by spacers 22 such that the perforated pipe 19 is supported away from the bottom of the basin 4. This allows water to flow below the perforated pipe 19 and avoids formation of puddles. In other embodiments the perforated pipe 19 is placed on the bottom of the basin 4. The perforated pipe 19 is connected to the main gas pipe 23, which in this embodiment is not embedded in the water-permeable layer 5.

As an optional feature, a permeable mat 45 is situated underneath the perforated film 40, directly on top of the granular material 5 that has been filled in the basin.

The mat 45, preferably, forms a stabilizing mat on top of the granular layer 5.

For example, the mat 45 is a three-dimensional open structured geomat, e.g. produced from thermally bonded extruded polymer, e.g. polypropylene, monofilaments.

In an embodiment, the mat 45 is a capillary mat 45 which has a capillary action in the horizontal direction and in the vertical direction, for example a non-woven mat of fibrous elements, for example a compacted non-woven mat. As a result thereof, transportation of moisture underneath the film is also possible in a horizontal direction, for example from plant to plant.

Alternatively, but less advantageously, the mat 45 is situated between the top fabric 17 and the perforated film 40.

The film 40 is closed as such, and therefore does not allow water or water vapour to pass, except at the location of the perforations 41 in the film 40.

In this way, the film 40 forms an, albeit imperfect, barrier to water, as it were, which, due to the (usually heated) climate in the greenhouse (or optionally due to heating in the cultivation floor itself) will want to evaporate from the layer 5 and rise up through the permeable structure and the permeable top fabric.

The film 40 significantly reduces the free evaporation surface, as it were. As a result thereof, water which has remained behind in the water-permeable structure 5 can evaporate much less readily. Furthermore, this vapor only rises up in the film 40 at the location of the perforations 41, as a result of which it is readily possible for the top fabric 17 to dry out in the regions between these perforations.

The size of the perforations 41 is preferably chosen to be such that the perforations do not impede a possible through-flow of water in an ebb/flood watering installation. For example, perforations 41 with diameters of between 1 mm and 12 mm or perforations with corresponding dimensions in terms of surface area are provided if a non-round shape is chosen.

For example, the distance between adjacent perforations 41 in the film 40 or between groups of smaller perforations is at least 10 mm, as a result of which dry zones can readily occur in the top fabric 17.

In a practical embodiment, a perforated film 40 is provided which is made of impermeable film material, e.g. of plastic film, which is provided with distributed perforations 41 having an average opening of between 0.75 mm² and 108 mm², wherein the perforations preferably form at most 10% of the surface area, if desired at most 5% of the surface area.

In an advantageous embodiment, the perforated film 40 is a single-layer plastic film.

The first aspect of the invention is not limited to the cultivation floor system described in Figures 1 and 2. The person skilled in the art can make various modifications which fall within the scope of the first aspect of the invention.

Fig. 3 diagrammatically shows a sports pitch floor system 101 to illustrate the second aspect of the invention. The sports pitch floor system 101 has been installed using a method according to the second aspect of the invention.

A watertight basin 104 is constructed first. The basin 104 has a bottom profile 112. Several U-shaped gullies 114 are provided in the bottom profile 112 and extend substantially parallel to each other. Although two gullies 114 are shown in Figure 1 , the bottom profile 112 may comprise significantly more gullies 114. On either side of each gulley 114, the bottom profile 112 comprises a bottom surface which runs off towards said gulley 114. After the bottom profile 112 has been formed, the bed of the bottom profile 112 is covered with a watertight ground sheet.

An irrigation line 107 is laid in each gulley 114. The irrigation lines 107, preferably, have a smooth, non-corrugated peripheral wall.

The irrigation lines 107 are, for example, formed by plastic pipes with smooth walls, such as PVC pipes. The outer diameter of the irrigation lines 107 corresponds to the curvature of the bottom of the U-shaped gullies 114, in other words the gullies 114 are produced with a cross section which corresponds to the cross section of at least the bottom portion of the irrigation line 107 to be accommodated therein. As is illustrated in Figure 4, this results in a top portion of an irrigation line 107 which is accommodated in a gulley 114 being exposed.

When installing the irrigation lines 107, each irrigation line 107 may already have been provided with several openings 108, which are a distance apart in the longitudinal direction of this irrigation line 107, for example equidistant from each other. Instead, it is also possible for one or more irrigation lines 107 to be configured such that they are initially closed, that is to say have a closed pipe wall, in which case the openings 108 are made after these irrigation lines 107 have been accommodated in the gullies 114 and preferably in the exposed top portion of these irrigation lines 107.

The openings 108 can be made in the irrigation lines 107 in different ways. The openings 108 are, for example, made using a tool which is provided with a base comprising guide means, for example wheels, which are configured to engage with an irrigation line 107. The tool can be placed on an irrigation line 107 and moved along the irrigation line 107. At a location where an outflow opening 108 is desired, the tool may perform an operation on the irrigation line 107 to form the outflow opening 108, for example by drilling, milling, sawing, burning, cutting, or punching.

The irrigation lines 107 are connected to a water supply and discharge system 103 which comprises a water storage 111 and a water pump 110. The irrigation lines 107 are, as is an option, further connected to a gas pump 121.

After the irrigation lines 107 have been accommodated in the gullies 114 and provided with openings 108, water may be supplied to the irrigation lines 107 by means of the water pump 110.

In an embodiment, the emerging flow of water from the irrigation lines 107 is monitored, for example visually, by an individual or by a measuring system (not shown). If undesired deviations in the emerging flow are observed, the effective emerging flow is adjusted in situ by providing the irrigation lines 107 with one or more additional openings 108 or by increasing the dimensions of one or more openings 108 at a location where the emerging flow is considered to be too small and/or by closing one or more openings 108 in the irrigation lines or by reducing the dimensions of one or more openings 108 at a location where the emerging flow is considered to be too large. If necessary, the steps of supplying water, monitoring and adjusting the effective emerging flow are repeated one or more times until a desired uniform emerging flow of water from the irrigation lines 107 is achieved.

Subsequently, a water-permeable structure 105 is arranged in the basin 104. The water- permeable structure 105 comprises one or more layers of granular material. The irrigation lines 107 are covered by the water-permeable structure 105.

An elongate, readily water-permeable strip of gauze or an open fabric may be laid over the irrigation line 107 which is provided with openings, which strip is configured to prevent granular material from penetrating into the openings 108, and which strip preferably covers edge regions of the basin bottom which border the irrigation line 107.

The compacting of the one or more layers of loose granular material is performed, so as to provide a stable permeable granular material structure in the basin.

A substantially horizontal top surface of the compacted permeable granular material is provided at a level below the top edge of the perimeter of the watertight basin. The horizontality is desired in view of obtaining a uniformity of the water level when filling water into the basin to the water level being in contact with the sports floor.

The top surface of the compacted permeable granular material is covered by a water- permeable fabric 117, e.g. a (woven) cloth or a mat, e.g. said cloth or mat being spooled from a roll, e.g. adjacent webs being secured to one another along their edges.

Preferably, the water-permeable fabric 117 is secured to the perimeter of the basin, at a height below the top edge of the perimeter of the basin.

The water-permeable cloth or mat 117 allows water to first be distributed evenly through the water-permeable structure 105 before being supplied to the sports pitch floor 102 through the water permeable mat or cloth 117. The water-permeable cloth or mat 117 prevents parts of the sports pitch floor 102, e.g. soil or clay, from entering in the water-permeable structure 105 which negatively influences the supply of water to the sports pitch floor by negatively influencing the distribution of water through the water-permeable structure 105.

The sports pitch floor 102 is installed over the permeable cloth or mat 117. Preferably, the floor 102 has a thickness such that the top of the perimeter of the basin is lower than the top of the floor 102, e.g. the floor 102 extending over the perimeter so that the perimeter is hidden, e.g. does not form an obstacle.

In the embodiment of figure 3, the sports pitch floor 102 comprises soil 109 and grass 106, which grass is only depicted on a small portion of the sports pitch floor 102.

With the sports pitch floor system 101 a particularly uniform water supply can be achieved. The combination of an ebb/flood system 103 for providing water to irrigation lines 107 which are provided in a water-permeable structure 105 which is separated from the sports pitch floor 102 by a water-permeable math 117 or cloth provides for uniform and controlled water supply to the sports pitch floor 102. It is known that a sports pitch floor 102 with a suboptimal humidity is easily damaged, e.g. a clay floor may easily crack. The second aspect of the invention allows for optimal conditions of the sports pitch floor 102 to perform sports and for increasing the rate of recovery of the sports pitch floor afterwards.

For example, the system may be used to make the roots of the grass 106 longer by gradually reducing the water level in the sports pitch floor system 101 over time. The grass roots will grow longer in order to follow the reducing water level. A result of this is grass with longer roots which is stronger and more resilient to damage. The result is grass which is better suited to perform sports on and a sports pitch floor 102 which has to be replaced less often.

Figure 4 shows a cross section of a part of the sports pitch floor system 101. The figure shows the basin 104 and a gulley 114 which is provided in the bottom profile 12. The sports pitch floor system 101 may require as many gullies 114 as required. An irrigation line 107 is provided in the gulley 114, which irrigation line 107 comprises openings 108 at a top side thereof. In embodiments openings 108 may also be provided on a bottom side of the irrigation line 107 in order to prevent water from gathering in the gulley 114. On either side of each gulley 114, the bottom profile 112 comprises a bottom surface which runs off towards said gulley 114. This allows water in the basin 104 to flow easily towards the irrigation line 107 for drainage of the basin 104.

The basin 104 and irrigation line 107 are covered by the water permeable structure 5. The water permeable structure 105 comprises a granular material such as volcanic rocks or coarse sand. The sports pitch floor 102 is provided above the water-permeable structure 105 and between the sports pitch floor 102 and the water-permeable structure 105 the water permeable cloth or mat 117 is provided. The sports pitch floor 102 in this embodiment comprises soil 109 and grass 106 planted in the soil. In embodiments the sports pitch floor 102 comprises a combination 106 of natural grass and artificial turf, e.g. injected artificial turf filaments, for performing sports thereon.

In embodiments, the sports pitch floor 102 comprises clay for performing sports thereon, e.g. tennis.

In embodiments, the sports pitch floor is designed as a riding surface of an arena for equestrian sports. For example, the floor is in majority, e.g. substantially completely, composed of sand, e.g. sand mixes. For example, the top layer consists of sand only or with a proportion of fibre. The equestrian sports floor is kept moist from beneath by suitable operation of the water supply and discharge system. This allows for a consistent degree of moisture in the arena. It may also avoid loss of the finest fraction of the sand, which tends to be blown away by the wind when the floor surface becomes too dry.

Fig. 5 diagrammatically shows an installation or facility 201 to illustrate the third aspect of the invention. The installation or facility 201 has been installed as follows.

A watertight basin 204 is constructed. The basin 204 has a bottom profile 12, which is produced in a base, e.g. the ground.

Several U-shaped gullies 214 are provided in the bottom profile 212 and extend substantially parallel to each other. Although two gullies 214 are shown in Figure 5, the bottom profile 212 may comprise significantly more gullies 214. On either side of each gulley 214, the bottom profile 212 comprises a bottom surface which runs off towards said gulley 214. After the bottom profile 212 has been formed, the bottom profile 212 is covered with a watertight ground sheet.

An irrigation line 207 is laid in each gulley 214. The irrigation lines 27, preferably, have a smooth, non-corrugated peripheral wall.

The irrigation lines 207 are, for example, formed by plastic pipes with smooth walls, such as PVC pipes. The outer diameter of the irrigation lines 207 corresponds to the curvature of the bottom of the U-shaped gullies 214, in other words the gullies 214 are produced with a cross section which corresponds to the cross section of at least the bottom portion of the irrigation line 207 to be accommodated therein. As is illustrated in Figure 6, this results in a top portion of an irrigation line 207 which is accommodated in a gulley 214 being exposed. When installing the irrigation lines 207, each irrigation line 207 may already have been provided with several openings 208, which are a distance apart in the longitudinal direction of this irrigation line 207, for example equidistant from each other. Instead, it is also possible for one or more irrigation lines 207 to be configured such that they are initially closed, that is to say have a closed pipe wall, in which case the openings 208 are made after these irrigation lines 207 have been accommodated in the gullies 214 and preferably in the exposed top portion of these irrigation lines 207.

The openings 208 can be made in the irrigation lines 207 in different ways. The openings 208 are, for example, made using a tool which is provided with a base comprising guide means, for example wheels, which are configured to engage with an irrigation line 207. The tool can be placed on an irrigation line 207 and moved along the irrigation line 207. At a location where an outflow opening 208 is desired, the tool may perform an operation on the irrigation line 207 to form the outflow opening 8, for example by drilling, milling, sawing, burning, cutting, or punching.

The irrigation lines 207 are connected to a water supply and discharge system 203 which comprises a water storage 211 and a water pump 210. The irrigation lines 207 may be further connected to a gas pump 221.

After the irrigation lines 207 have been accommodated in the gullies 214 and provided with openings 208, water may be supplied to the irrigation lines 207 by means of the water pump 210.

In an embodiment, the emerging flow of water from the irrigation lines 207 is monitored, for example visually, by an individual or by a measuring system (not shown). If undesired deviations in the emerging flow are observed, the effective emerging flow is adjusted in situ by providing the irrigation lines 207 with one or more additional openings 208 or by increasing the dimensions of one or more openings 208 at a location where the emerging flow is considered to be too small and/or by closing one or more openings 208 in the irrigation lines or by reducing the dimensions of one or more openings 208 at a location where the emerging flow is considered to be too large.

If necessary, the steps of supplying water, monitoring and adjusting the effective emerging flow are repeated one or more times until a desired uniform emerging flow of water from the irrigation lines 207 is achieved. Subsequently, a water-permeable structure 205 is arranged in the basin 4. The water- permeable structure 205 comprises one or more layers of granular material. The irrigation lines 207 are covered by the water-permeable structure 205.

An elongate, readily water-permeable strip of gauze or an open fabric may be laid over the irrigation line 207 which is provided with openings, which strip is configured to prevent granular material from penetrating into the openings 208, and which strip preferably covers edge regions of the basin bottom, which border the irrigation line 207.

A compacting of the one or more layers of loose granular material is performed, so as to provide a stable permeable granular material structure in the basin.

A substantially horizontal top surface of the compacted permeable granular material is provided at a level at or, preferably, below the top edge of the perimeter of the watertight basin. The horizontality is desired in view of obtaining a desired degree of uniformity of the water level when filling water into the basin to the water level being in contact with the bed of soil.

The top surface of the compacted permeable granular material is covered by a water- permeable fabric 217, e.g. a (woven) cloth or a mat, e.g. said cloth or mat being spooled from a roll, e.g. adjacent webs being secured to one another along their edges.

Preferably, the water-permeable fabric 217 is secured to the perimeter of the basin, preferably at a height below the top edge of the perimeter of the basin.

The water-permeable cloth or mat 217 allows water to first be distributed evenly through the water-permeable structure 205 before being supplied to the bed of soil 202 through the water permeable mat or cloth 217. The water-permeable cloth or mat 217 prevent soil from the bed 202 from entering in the water-permeable structure 205 which negatively influences the supply of water to the bed by negatively influencing the distribution of water through the water-permeable structure 205.

The bed of soil and/or growing medium 202 is installed over the permeable cloth or mat 217. Possibly walkway areas of the floor remain uncovered by the bed of soil. As the perimeter of the basin extends above the fabric 217, e.g. over about the height of the bed, e.g. up to or below the top of the bed, e.g. over or at least several centimetres, the perimeters contains the water within the bed during a flood period of the floor system.

In embodiments, further elongated barrier members are placed on the floor, delimiting compartments in the bed.

In the embodiment of figure 5, the bed 202 is used to grow harvestable crop 209.

With the floor system 201 a particularly uniform water supply is achieved. The combination of an ebb/flood system 203 for providing water to irrigation lines 207 which are provided in a water-permeable structure 205 which is separated from the bed 202 by a water-permeable mat 217 or cloth provides for uniform and controlled water supply to the bed 202.

For example, the system may be used to make the roots of the crop longer by gradually reducing the water level in the bed 202 over time. The roots will grow longer in order to follow the reducing water level. A result of this is a crop with longer roots. The roots will not grow through the fabric, or only to a minimal extent.

Figure 6 shows a cross section of a part of the installation 201. The figure shows the basin 204 and a gulley 214 which is provided in the bottom profile 212. The installation 201 may have as many gullies 214 as required. An irrigation line 207 is provided in the gulley 214, which irrigation line 207 comprises openings 208 at a top side thereof. In embodiments, the openings 208 may also be provided on a bottom side of the irrigation line 207 in order to prevent water from gathering in the gulley 214. On either side of each gulley 214, the bottom profile 212 comprises a bottom surface which runs off towards said gulley 214. This allows water in the basin 204 to flow easily towards the irrigation line 207 for drainage of the basin 204.

The basin 204 and irrigation line 207 are covered by the water permeable structure 205. The water permeable structure 205 comprises a granular material such as volcanic rocks, e.g. lava granules, or coarse sand.

The bed 202, e.g. of between 10 and 40 centimetres thick, is installed over the water- permeable structure 205 and between the bed 202 and the water-permeable structure 205 the water permeable cloth or mat 217 is provided. Figure 7 illustrates an example of the fourth aspect of the invention.

The tillage device 501 is configured and operated to perform tillage operations of the soil bed 202, e.g. after a crop has been harvested and a new crop is to be planted in the soil bed.

The tillage device 501 comprises a frame, e.g. a vertically adjustable frame 504, which is schematically depicted. The frame 504 may be supported by associated wheels, not shown, and/or by a vehicle, not shown, or any other suitable support means.

The frame 504 may comprise height adjusting means for vertically adjusting the height of the frame 504.

The tillage device 501 further comprises rigid tillage members 505 mounted to the frame 504, which are here depicted in the form of rotatable blades or rotary disc members. The rigid tillage members 505 are configured and operated to perform a tillage operation of an upper p layer of the soil bed 202, e.g. the majority of the thickness of the soil bed 202, such that the rigid tillage members 505 stay clear from and do to not contact the fabric 217 underneath the soil bed 202 during the tillage operation.

In the embodiment shown in figure 7, flexible tillage members 206 trail behind the rigid tillage members 205 during a tillage operation. The flexible tillage members 206 are here embodied as flexible fingers or flexible blades for performing a tillage operation of a lower layer of the soil bed 202. As can be seen from the figure 7, the flexible tillage members 206 penetrate deeper into the bed 202 than the rigid tillage members 205. In other embodiments, the flexible tillage members may be provided on a different place relative to the frame and/or the rigid tillage members, e.g. mounted on the rigid tillage members 205.

In embodiments, the flexible tillage members are flexible rotary blades or flexible rotary disc members.

The tillage device 501 further comprises a height sensor assembly 507 for measuring a height, here of the frame 504, relative to the fabric 217 underneath the soil bed. In this embodiment, the height sensor 507 is a laser sensor 507 which measures a laser beam LB which is emitted in a horizontal plane over the soil bed at a known height relative to the fabric 217. In case the bed itself would have a uniform and known thickness, one might use the bed as a reference, yet use of the fabric as reference is more reliable. This arrangement allows the height sensor to measure the height of the frame 504 relative to the laser beam LB and thus relative to the fabric 217.

The tillage device 501 further comprises a controller assembly 208 for controlling a height of the frame 504 and/or of the rigid tillage members relative to the fabric 217. For example, the controller controls height adjusting means for adjusting the height of the frame. The controller 508 is connected to the height sensor 507 for receiving the measured height of the frame 504. The controller 508 is configured to adjust the height of the frame, e.g. by controlling the height adjusting means, based on the measured height such that the rigid tillage members 505 do not contact the fabric 217 during operation of the tillage device 501.

Claims

C L A I M S

1. Cultivation floor system (1) with a cultivation floor (2) on which plant containers (6) are placeable, comprising: a watertight basin (4) comprising a bottom (16) and a perimeter; a water-permeable structure (5) comprising at least a layer of a granular material, e.g. lava granules, filled in the basin (4); a permeable top fabric (17) which covers the water-permeable structure (5) and which forms a top side of the floor (2) on which plant containers (6) are placeable, a perforated film (40) placed under the permeable top fabric (17), which perforated film (40) is made of impermeable film material which is provided with distributed perforations (41), which film reduces the free evaporation surface for water from the water-permeable structure (5), an ebb/flood watering installation which is configured to supply water so that water is available for the plants in the plant containers (6) and comprises one or more irrigation lines (7) on the bottom of the basin (4) covered by the water-permeable structure, which irrigation lines (7) have openings (8) along their length, the installation being configured for water to flow from the one or more irrigation lines (7) to flood the basin to a level above the permeable top fabric (17) and to relief water from the basin, characterized in that the cultivation floor system (1) further comprises a gas supply and distribution system (18,

19, 23), for example for supply of air and/or CO2, wherein the gas supply and distribution system (18, 19, 23) comprises a network (19, 23) of gas supply lines distinct from the irrigation lines and configured for distributing a gas across the floor (2), which network (19,

23) is provided in the basin lower than the perforated film (40), preferably embedded in the water-permeable structure or on the bottom of the basin, and wherein the gas supply and distribution system further comprises a gas supplying installation (18) for supplying gas to the network (19, 23) so that, in use, the gas flows from the network (19, 23) through the perforations (41) of the perforated film (40) and reaches the plant containers (6) placed on the floor (2).

2. Cultivation floor system according to claim 1 , wherein the network (19, 23) for distributing gas is provided at least 5 cm below the top fabric (17).

3. Cultivation floor system according to claim 1 or 2, wherein the network (19, 23) for distributing gas is embedded in the water-permeable structure, e.g. in the layer of granular material.

4. Cultivation floor system according to any one or more of claims 1 - 3, wherein the network (19, 23) for distributing gas comprises one or more perforated gas distribution lines having along the length thereof perforations for emitting the gas, e.g. with an inlet connected to a main gas pipe and with a closed end, e.g. multiple perforated gas distribution lines extending parallel to one another from a common main gas pipe, e.g. perpendicular to the main gas pipe.

5. Cultivation floor system according to any one or more of claims 1 - 4, wherein the watering installation comprises multiple parallel irrigation lines (7), and wherein one or more main gas pipes (23) extend parallel to the irrigation lines, e.g. each main gas pipe centered between a pair of adjacent irrigation lines, and wherein perforated gas distribution lines branch off from each main gas pipe, e.g. in opposite directions, e.g. perpendicular to the main gas pipe.

6. Cultivation floor system according to any one or more of claims 1 - 5, wherein the network comprises a main gas pipe (23), e.g. which extends parallel to the irrigation lines, e.g. centered between a pair of irrigation lines, and wherein perforated gas distribution lines branch off from the main gas pipe in opposite directions, e.g. perpendicular to the main gas pipe.

7. Cultivation floor system according to any one or more of claims 1 - 6, wherein the network comprises a main gas pipe (23), e.g. which extends parallel to the irrigation lines, e.g. centered between a pair of irrigation lines, the main gas pipe having a length of at least 25 meters, and wherein perforated gas distribution lines branch off from the main gas pipe in opposite directions, e.g. perpendicular to the main gas pipe, each perforated gas distribution line having a blind end and a length of between 3 and 5 meters.

8. Cultivation floor system according to any one or more of claims 1 - 7, wherein the network (19, 23) for distributing gas comprises perforated gas distribution lines having along the length thereof perforations for emitting the gas, e.g. with an inlet connected to a main gas pipe and with a closed end, wherein multiple perforated gas distribution lines extend, e.g. parallel to one another from a common main gas pipe, e.g. perpendicular to the main gas pipe, and wherein a flow rate adjusting device is present at the inlet of each perforated gas distribution line.

9. Cultivation floor system according to one or more of the preceding claims, wherein the network (19, 23) is supported at a distance above the bottom (16) of the basin (4) by spacers (22) that are placed on the bottom (16) of the basin (4), e.g. prior to filling granular material in the basin.

10. Cultivation floor system according to one or more of the preceding claims, wherein the gas supply and distribution system (18, 19, 23) is adapted to heat and/or cool the gas before distributing the gas, e.g. air, via the network across the surface of the floor (2).

11. Method for growing plants in plant containers, preferably in a greenhouse, wherein use is made of a cultivation floor system (1) according to one or more of the preceding claims 1 10

12. Method for growing plants according to claim 11, wherein the gas supply and distribution system (18, 19, 23) is adapted to heat and/or cool the gas before distributing the gas across the floor (2), and wherein the method comprises heating and/or cooling the gas before distributing the gas via the network.

13. Method according to claim 11 or 12, wherein the gas supply and distribution system (18, 19, 23) is operated to reduce or avoid growth of roots out of the container, e.g. by effecting or enhancing a drying out of the floor.

14. Method for installing a cultivation floor system (1) comprising a cultivation floor (2) configured for placing plant containers (6) thereon, which method comprises:

- providing a watertight basin (4) having a bottom and a perimeter with a top edge;

- placing one or more irrigation lines (7) on the bottom in the basin (4), which irrigation lines (7) each have a multitude of openings (8) along their length for passage of water through said openings (8),

- connecting a watering installation, e.g. a water supply and discharge system including a water pump (10), to the one or more irrigation lines (7);

- installing a gas supply and distribution system (18, 19, 23) comprising a network (19, 23) for distributing gas which is installed in the basin (4);

- filling into the basin one or more layers of loose granular material, e.g. lava granules; - compacting the one or more layers of loose granular material so as to provide permeable granular material structure (5) in the basin (4), wherein the one or more irrigation lines (7) and the network for distributing gas are covered by the granular material structure (5),

- covering the top surface of the compacted permeable granular material by a water- permeable top fabric (17), e.g. a (woven) fabric or a mat, with a perforated film (40) being placed under the permeable top fabric, which perforated film is made of impermeable film material which is provided with distributed perforations (41), wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines (7) so that the water-permeable granular material structure (5) in the basin (4) is flooded with water and the water level is above the water-permeable fabric (17), which water level is maintained for a flood period so that water is absorbable by the plants in the plant containers, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines (7) so that the water-permeable granular material structure (5) in the basin (4) is relieved from the water after the flood period and wherein the gas supply and distribution system (18, 19, 23) is configured to cause a supply of gas via the network and through the perforations (41) of the perforated film (40) to reach plant containers (6) placed on the floor (2).

15. Greenhouse provided with a cultivation floor system (1) according to one or more of the claims 1-10 and/or wherein use is made of a method according to one or more of the claims 11 - 13.

16. Method for installing a sports pitch floor system (101) comprising a sports pitch floor (102) configured for performing a sport thereon, e.g. the sports pitch floor having a natural vegetation, e.g. grass, which method comprises:

- providing a watertight basin (104) having a bottom and a perimeter with a top edge;

- placing one or more irrigation lines (107) in the basin (104), which irrigation lines (107) have a multitude of openings (8) along their length for passage of water, possibly also of a gas, e.g. air and/or C02, through said openings (108),

- connecting a water supply and discharge system including a water pump (110) to the one or more irrigation lines (107); - filling into the basin one or more layers of loose granular material, e.g. lava granules;

- compacting the one or more layers of loose granular material so as to provide permeable granular material structure (105) in the basin (104), wherein the one or more irrigation lines (107) are covered by the granular material structure (105),

- covering the top surface of the compacted permeable granular material by a water- permeable fabric (117), e.g. a (woven) cloth or a mat,

- installing a sports pitch floor (102) on top of the water-permeable fabric, wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines (107) so that the water-permeable granular material structure (105) in the basin (104) is flooded with water and the water level is above the water- permeable fabric (117), which water level is maintained for a flood period so that water is present in, e.g. absorbed by, the sports pitch floor (102), e.g. at least in part by the natural vegetation, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines (107) so that the water-permeable granular material structure (105) in the basin (104) is relieved from the water after the flood period.

17. Method according to claim 16, wherein the method further comprises providing a gas supply and distribution system (18, 19, 23), for example for supply of air and/or C02, wherein the gas supply and distribution system (18, 19, 23) comprises a network (19, 23) of gas supply lines distinct from the irrigation lines and configured for distributing a gas across the floor (102), which network (19, 23) is provided in the basin, preferably embedded in the water-permeable structure or on the bottom of the basin, and wherein the gas supply and distribution system further comprises a gas supplying installation (18) for supplying gas to the network (19, 23) so that, in use, the gas flows from the network (19, 23).

18. Sports pitch floor system (101) with a sports pitch floor (102) configured for performing a sport thereon, which sports pitch floor system (101) comprises:

- a watertight basin (104) having a bottom and a perimeter with a top edge;

- one or more irrigation lines (107) placed in the basin (104), which irrigation lines (107) have a multitude of openings (108) along their length for passage of water, possibly also of a gas, e.g. air and/or C02, through said openings (108), - a water supply and discharge system including a water pump (110) connected to the one or more irrigation lines (107);

- one or more layers of loose granular material, e.g. lava granules, filled in the basin; said one or more layers of loose granular material being compacted so as to provide permeable granular material structure (105) in the basin (104), wherein the one or more irrigation lines (107) are covered by the granular material structure (105),

- a water-permeable fabric (117), e.g. a (woven) cloth or a mat, covering the top surface of the compacted permeable granular material,

- a sports pitch floor (102) on top of the water-permeable fabric, wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines (107) so that the water-permeable granular material structure (105) in the basin (104) is flooded with water and the water level is above the water- permeable fabric (117), which water level is maintained for a flood period so that water is present in, e.g. absorbed by, the sports pitch floor (102), e.g. at least in part by the natural vegetation, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines (107) so that the water-permeable granular material structure (105) in the basin (104) is relieved from the water after the flood period.

19. Method for growing and harvesting natural grass sods, e.g. for use on a sports pitch, wherein the grass is grown in a bed of soil so that roots develop within the bed and the grass grows, the grown grass being harvested as grass sods, wherein the bed of soil is installed on a floor system, wherein the floor system (101) comprises:

- a watertight basin (104) having a bottom and a perimeter with a top edge;

- one or more irrigation lines (107) placed in the basin (104), which irrigation lines (107) have a multitude of openings (108) along their length for passage of water, possibly also of a gas, e.g. air and/or C02, through said openings (108),

- a water supply and discharge system including a water pump (110) connected to the one or more irrigation lines (107);

- the compacted permeable granular material having a substantially horizontal top surface at a level at or below the top edge of the perimeter of the watertight basin, - a water-permeable fabric (117), e.g. a cloth, e.g. a woven cloth, or a mat, covering the top surface of the compacted permeable granular material, wherein the bed of soil (109) is installed on top of the water-permeable fabric, wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines (107) so that the water-permeable granular material structure (105) in the basin (104) is flooded with water and the water level is above the water- permeable fabric (117), which water level is maintained for a flood period so that water is absorbed by the bed (102) and the grass, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines (107) so that the water-permeable granular material structure (105) in the basin (104) is relieved from the water after the flood period, wherein the grown grass is harvested as grass sods.

20. Installation (201) for growing and harvesting a crop, wherein the crop is planted in a bed of soil and/or growing medium, so that roots of the crop develop within the bed and the crop grows, the grown crop being harvested, wherein the installation comprises a bed of soil and/or growing medium that is installed on a floor system, wherein the floor system comprises:

- a watertight basin (204) having a bottom and a perimeter with a top edge;

- one or more irrigation lines (207) placed in the basin (204), which irrigation lines (207) have a multitude of openings (208) along their length for passage of water, possibly also of a gas, e.g. air and/or C02, through said openings (208),

- a water supply and discharge system (203) including a water pump (210) connected to the one or more irrigation lines (207);

- one or more layers of loose granular material, e.g. lava granules, filled in the basin; said one or more layers of loose granular material being compacted so as to provide permeable granular material structure (205) in the basin (204), wherein the one or more irrigation lines (207) are covered by the granular material structure (205),

- a water-permeable fabric (217), e.g. a (woven) cloth, e.g. a woven cloth, or a mat, covering the top surface of the compacted permeable granular material, wherein the bed of soil and/or growing medium (202) is installed on top of the water- permeable fabric (217), wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines (207) so that the water-permeable granular material structure (205) in the basin (204) is flooded with water and the water level is above the water- permeable fabric (217), which water level is maintained for a flood period so that water is absorbed by the bed (202) and the crop, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines (207) so that the water-permeable granular material structure (205) in the basin (204) is relieved from the water after the flood period.

21. Installation according to claim 20, wherein a gas supply and distribution system (18, 19, 23) is provided, for example for supply of air and/or C02, wherein the gas supply and distribution system (18, 19, 23) comprises a network (19, 23) of gas supply lines distinct from the irrigation lines and configured for distributing a gas across the floor (102), which network (19, 23) is provided in the basin, preferably embedded in the water-permeable structure or on the bottom of the basin, and wherein the gas supply and distribution system further comprises a gas supplying installation (18) for supplying gas to the network (19, 23) so that, in use, the gas flows from the network (19, 23) through the one or more layers of loose granular material.

22. Method for growing and harvesting a crop, wherein the crop is planted in a bed of soil and/or growing medium so that roots of the crop develop within the bed and the crop grows, the grown crop being harvested, wherein the bed of soil and/or growing medium is installed on a floor system, wherein the floor system (201) comprises:

- a watertight basin (204) having a bottom and a perimeter with a top edge;

- one or more irrigation lines (207) placed in the basin (204), which irrigation lines (207) have a multitude of openings (8) along their length for passage of water, possibly also of a gas, e.g. air and/or C02, through said openings (208),

- a water supply and discharge system including a water pump (210) connected to the one or more irrigation lines (207);

- one or more layers of loose granular material, e.g. lava granules, filled in the basin; said one or more layers of loose granular material being compacted so as to provide permeable granular material structure (205) in the basin (204), wherein the one or more irrigation lines (207) are covered by the granular material structure (205), - the compacted permeable granular material having a substantially horizontal top surface at a level at or below the top edge of the perimeter of the watertight basin,

- a water-permeable fabric (217), e.g. a cloth, e.g. a woven cloth, or a mat, covering the top surface of the compacted permeable granular material, wherein the bed of soil and/or growing medium (202) is installed on top of the water- permeable fabric, wherein the water supply and discharge system is configured to cause a supply of water via the one or more irrigation lines (207) so that the water-permeable granular material structure (205) in the basin (204) is flooded with water and the water level is above the water- permeable fabric (217), which water level is maintained for a flood period so that water is absorbed by the bed (202) and the crop, and wherein the water supply and discharge system is configured to cause a discharge of water via the one or more irrigation lines (207) so that the water-permeable granular material structure (205) in the basin (204) is relieved from the water after the flood period.

23. A method for growing and harvesting a crop, wherein the crop is planted in a bed of soil so that roots of the crop develop within the bed and the crop grows, the grown crop being harvested, wherein the bed of soil (202) is installed on a floor system, wherein the floor system (201) comprises:

- a watertight basin (204) having a bottom and a perimeter with a top edge;

- one or more irrigation lines (207) placed in the basin (204),

- one or more layers of loose granular material, e.g. lava granules, filled in the basin and forming a water-permeable granular material structure (205) in the basin (204), wherein the one or more irrigation lines (207) are covered by the granular material structure (205),

- a water-permeable fabric (217), e.g. a cloth, e.g. a woven cloth, or a mat, covering the top surface of the compacted permeable granular material, wherein the bed of soil (202) is installed on top of the water-permeable fabric, wherein, e.g. after harvesting a grown crop, the bed of soil is subjected to a tillage operation, wherein use is made of a tillage device (501) which comprises:

- a frame (504) that is configured and operated so as to be moved over the bed of soil

(202), - rigid tillage members (505), e.g. rigid rotary tillage members, supported by the frame (504) and configured and operated to perform a tillage operation on an upper layer of the soil bed (202);

- flexible tillage members (506), e.g. supported by the frame (504) and/or by the rigid tillage members (505), configured and operated to perform a tillage operation on a lower layer of the soil bed (202);

- a height sensor assembly (507) for measuring a height of the frame (504) and/or of the rigid tillage members (505) relative to the water-permeable fabric (217); and

- a controller assembly (508) for controlling a height of the frame (504) and/or of the rigid tillage members (505) relative to the water-permeable fabric (217), which controller assembly (508) is connected to the height sensor assembly (507), wherein the controller assembly (508) is configured and operated to adjust the height of the rigid tillage members (505) relative to the water-permeable fabric (217) based on the measured height such that the rigid tillage means (505) remain clear from the water- permeable fabric (217) during the tillage operation, so that the upper layer of the soil bed is subjected to tillage by said rigid tillage members, and wherein the method comprises tillage of the lower layer of the soil bed by means of the flexible tillage members.

24. A tillage device for subjecting a soil bed to a tillage operation, which tillage device comprises:

- a vertically adjustable frame (504) that is configured so as to be moved over the bed of soil,

- rigid tillage members (505), e.g. rigid rotary tillage members, supported by the frame and configured to perform a tillage operation on an upper layer of the soil bed;

- flexible tillage members (506), e.g. supported by the frame and/or by rigid tillage members, configured to perform a tillage operation on a lower layer of the soil bed;

- a height sensor assembly (507) for measuring a height of the frame and/or of the rigid tillage members relative to a reference level, e.g. a water-permeable fabric (217) underneath the soil bed; and

- a controller assembly (508) for controlling a height of the frame and/or of the rigid tillage members relative to the reference level, which controller assembly is connected to the height sensor assembly, wherein the controller assembly (508) is configured to adjust the height of the frame and/or of the rigid tillage members relative to the reference level (217) based on the measured height such that the rigid tillage members (505) - in operation - remain clear from the reference level during the tillage operation.