NL2001720C2

NL2001720C2 - Vegetable i.e. leek, growing method, involves providing light-tight cover on frame that comprises holes, allowing vegetable plants to pass through holes, and increasing height of cover for following growth of plants

Info

Publication number: NL2001720C2
Application number: NL2001720A
Authority: NL
Inventors: Johannes Petrus Maria Botman
Original assignee: Stichting Dienst Landbouwkundig Onderzoek
Priority date: 2008-06-25
Filing date: 2008-06-25
Publication date: 2009-12-30

Abstract

The method involves providing vegetable plants (5) at end positions on a tray (2), and providing water and nutrients to the plants by using a watering system. Crop protection agents are sprayed over the plants. A light-tight cover (9) is provided on a frame (8) that comprises holes at the end positions. The vegetable plants are allowed to pass through the holes, where the cover is arranged at a height with respect to the tray. The height of the cover is increased for following the growth of the plants. An independent claim is also included for a system for growing vegetables.

Description

5

P6021625NL

Method and system for growing vegetables like leek or similar vegetables which have at least a part which should not be exposed to light

Background

The present invention relates to a method and system for growing vegetables like leek or similar vegetables which have a part which should not be exposed to light.

10 “Cropping systems for field vegetables have to change fundamentally in the next years”. That is the conclusion of a study “Voeten op de grond en de blik vooruit” (Stoll, 2007), published by the growers organisation (organisation of Dutch growers, LTO). This will be necessary because of developments in the market and legislation.

15

The structure of the vegetables market changed in the last 10 years. The delivery of the products by vegetable growers is less and less to wholesalers and auctions and more and more directly to retailers. It is expected that this development will continue over the next years. Because of this trend, vegetable growers more often receive specific 20 demands from retailers regarding presentation, quality, package, taste, contents and in particular regarding continuous delivery of product during the season or even whole year. These demands requires a good managing of the growing process to influence production, harvest period, size, taste etc.

25 Growing field vegetables outdoors and directly in the soil cannot fulfil, the above-mentioned factors sufficiently.

Therefore, new growing systems for field production have to be developed which make better control of growth and production possible.

30

Furthermore, labour costs are the main part in the production costs of Dutch vegetables. A decrease of the labour costs per unit of product will strengthen the international competitive position for delivery in future.

2

Furthermore, new national and international legislation and regulation concerning mineral emissions and quality of groundwater and surface water can in the future result in such strict regulations that growing vegetables of sufficient quality in some areas in 5 the Netherlands will be almost impossible. The growers as well as the Dutch administration realize that only optimising of the actual growing processes is inadequate to reach the required water quality. Especially the relatively large field vegetables cultivation on sandy soils in the southeast of the Netherlands seems to be impossible in future.

10 A vegetable like leek is grown on about 3.000 ha in the Netherlands and 27.000 ha in the European Union. Total production in the Netherlands is reaching 100 kton. Almost all the leek is grown on sandy soils which are susceptible for leaching of nitrate and phosphate. For leek, various cropping periods exist, but summer leek, autumn leek, 15 winter leek and late winter leek are the most important. In the Netherlands, leek is planted from March until July and harvested from June until May. It can thus be harvested almost year-round. In winter, leek can suffer from frost damage. Most of the leek is grown in autumn and winter periods. In these periods there is a high risk that minerals which were supplied before and during growth leach into deeper soil layers.

20 This leaching even increases as fertilization requirements of leek are high (about 280-300 kg nitrogen/ha) whilst the nutrient efficiency of leek on the other hand is rather low.

On top of this, problems occur with various pests and diseases. Regular spraying is 25 necessary and for some (soil bom) diseases no treatment is available. In order to reduce disease risks, leek is therefore planted in rows which are 60-75 cm apart and at about 16 plants m2. This results in an average net production of about 25 - 50 ton/ha. Up to 50% of the harvested product is thrown away during the cleaning of the leek before trade.

30

Quality requirements for leek usually are: A white shaft of at least 14 cm; - Thickness between 2-4 cm, 3 - healthy clean, firm leek with dark green leaf colour.

The leek grower asks for leek cultivars that are productive, with high disease resistance, easy to clean and with a closed shaft to prevent soil particles within the leek.

5

Environment requirements and the necessity of a constant quality and quantity throughout the year require more controlled growing systems. The outdoor soil is one factor of the unpredictability of harvest time and quality of field vegetables. ‘Soilless’ cultivation or ‘substrate’ cultivation of field vegetables could be a solution. More 10 controlled growing systems out of the soil are not new. In Dutch glasshouses, cropping systems were developed in the last 25 years to grow tomatoes, peppers and other crops out of the soil. The current methods, however, are not suited

It is expected that growing leek out of the soil is desirable for the following reasons: 15 · To be better able to deliver high quality leek on the desired moment in the desired quantity because the dependency on external factors is decreasing.

• To be able to develop new products and product forms to create surplus value as leek free of soil particles, leek with a longer white shaft, leek with uniform thickness etc.

20 · To be able to improve labour efficiency and reduce labour costs by mechanization and automation of the production • To improve labour circumstances and to reduce the dependency on inferior season labour, which at the moment is mainly filled in by foreign labour. Cropping leek out of the soil requires more technical educated employees which corresponds more to 25 the local labour market. With better labour circumstances, the leek producers are more attractive for employees.

• To improve financial returns of leek growing. With a better financial return, growing of leek can be developed better together with new products. This makes a better cooperation in the chain possible with higher financial returns for all partners.

30 · To be able to better fulfil the legal requirements on nutrients and crop protection.

By using closed circulated systems. Emissions of nutrients and pesticides to ground-and surface water can be reduced drastically. Besides residues of pesticides on the 4 product can be reduced using other crop protection techniques. Besides, some pests and diseases will not occur any more by cropping out of the soil.

• To use water more efficient and to be able to supply crops better with sufficient water for optimal crop growth.

5 · To reduce the area needed to grow leek. Cropping out of the soil can be done with much higher amounts of plant per ha and can be done on non-suitable soils as well. Pressure on the most suitable soils can be reduced and soils can be used for other (less extensive) functions.

10 Growing vegetables which have at least a part which should not be exposed to light has several additional challenges which need to be met.

Summary of the Invention 15 The invention aims to provide a method and system for growing vegetables mentioned above.

According to a first aspect of the invention this is realized with a method of claim 1, and a system of claim 7.

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The system and method allow production of these vegetables in a controlled and more flexible manner. The cover provides support for the vegetable plants and at the same time shields at least part of the vegetable plant from light.

25 In the context of the current invention, the feature ‘vegetables which have a part which should not be exposed to light’ refers to those vegetables that have parts which should not be exposed to light in order to obtain a commercially acceptable product. Examples of such vegetables are leek, which usually has an almost white part. Another such vegetable is asparagus, for instance, which must remain completely white.

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Further embodiments of the invention are described in the depending claims and in the description of an embodiment below. Features of these embodiments may be claimed separately.

5

The method and system are used in the following way.

Seeds are seeded in small plant holders (1-5 cm diameter and 1-5 cm high), for instance 5 a fibemeth plug consisting of coir or pots filled with a medium to hold and support the young seedling. The plant holders are placed in or on trays or gullies. Both plant holder and tray or gully make unhampered root growth possible. The plant holders have to withstand frequent handling and transport to another place with minimum damage to the leek. It has to be possible to do this with automated machines.

10 When plants have a certain, predefined size at which they compete with each other for light, the plant holders with the leek plants are, automatically, transplanted from the seedling holders into another holding device with lower plant density. When the plants start competing again for light and harvest time is not yet reached spacing to less density will be repeated once or several times.

15

In an embodiment, at a certain, predefined, time before harvest the holding system will be provided with a cover to support the leek and block light in order to create the white shaft of leek. The cover is to exclude light under the cover and has holes. During planting the leek in the holder system, the cover is lying (almost) on top of holding 20 system. After planting the cover is pulled up to the desired height to get sufficient length of white shaft and support of the leek. The framework with the cover has therefore to be able to vary in height. Leek can be harvested, packed and sold with or without the plant holder.

25 Watering and fertilization can be done via an ebb-flood watering system or continuous flow or other watering systems. Crop protection agents can be given with the water or sprayed over the crop.

Vegetables harvested in or after periods with frost risk should be protected against frost 30 damage. For preventing frost damage, the vegetables can be transplanted/repositioned before these periods in polystyrene plates on a deep flow system. The plates are made to float on the water. The water in the deep flow system can be warmed, for instance with hoses where relative warm water is passed.

6

The invention further relates to an apparatus comprising one or more of the characterising features described in the description and/or shown in the attached drawings, and a method comprising one or more of the characterising features 5 described in the description and/or shown in the attached drawings.

The various aspects discussed in this patent can be combined in order to provide additional advantages.

10 Description of the Drawings

The invention will be further elucidated referring to an embodiment of a method and system shown in the attached drawings, showing in: 15 Figure 1 a tray with vegetable plants and light-tight cover;

Figure 2 a detail showing a vegetable plant in a growing pot;

Figure 3 part of the cover of figure 1 showing a through hole, and

Figure 4 a detail in cross section of a vegetable plant partly passing though a hole in the cover.

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Detailed Description of Embodiments

In figure 1, a tray with plants and cover according to the present invention is shown. The system 1 has a tray 2. Tray 2 is provided with an inlet 3 for water. This water 25 usually is provided with nutrients and if required with other additives. Tray 2 further has an outlet 4 for the supplied water.

In tray 2, in this embodiment the vegetable plants 5 are provided in growing pots 6. These growing pots 6 are here provided at end positions. In this drawing, only some 30 vegetable plants are shown. Usually, the vegetable plants are provided at regular matrix positions. For fixing the growing pots at their end positions, the tray is here provided with a retaining frame 7. This retaining frame 7 can have retaining provisions which may work together with retaining provisions on the growing pots for holding the 7 growing pots at their end positions. The retaining provisions can keep the end positions even if the vegetable plants are subject to heavy wind, for instance.

In this embodiment, attached to tray 2 is a frame 8 for holding the light-tight cover 9.

5 The system further has an actuator 11 which increases the distance between cover 9 and tray 2 or growing pots 2. This actuator can be an electro motor which extends the length of the struts, for instance. The actuator can be controller or steered. It is possible, for instance, to instruct the actuator to increase the distance with a fixed amount each period of time. It may also be possible to use measurement data for calculating the 10 required height. Alternatively, a farmer sets the height and the actuator just increase the height to that value. In an alternative, the height is hand-adjustable.

The sides of the tray may also be covered with a light-tight cover, not shown in the drawing, in order to prevent light from reaching part of the vegetable plant 5 below the 15 cover 9. In another embodiment, trays 2 can be positioned closely next to one another in such a way that the light-tight cover 9 overlaps or abuts in such a way that light (almost) does not enter below the cover 9.

Light-tight cover 9 is provided with through holes 10 at the end positions of the 20 vegetable plants. In that way, the cover 9 further provides support for the vegetable plants 5.

Figure 2 shows a vegetable plant 5, in this example leek, in a growing pot 6 in more detail. Usually, the growing pot is as small as possible. For leek, which will be 25 harvested at a thickness of between 2-4 cm, the pot will be about 3-6 cm in cross section. In this embodiment, the growing pot is circular in cross section, but other shapes may also be possible, for instance square. The pots may be a little tapered to the bottom (root-end). Usually, the growing pots are filled with a growing substrate. In an embodiment, the lower side of the growing pot 6 is open, to provide water to reach the 30 plant. The lower side may also be perforated. The roots 12 of the plant come out of the growing pot 6. The growing pots may be produced from plastic. It may also be produced from bio-degradable plastic or other bio-degradable material.

8

Figure 3 shows a detail of the light-tight cover 9. This cover blocks so much light that part of a leek, for instance, remains almost white. In an embodiment, one side of the cover 9 is white, and the other side is black in order to absorb any indirect lighting.

5 The cover 9 can be a plastic foil supported by a frame. In another embodiment, the cover 9 may comprise a (fibre) reinforced plastic foil.

Cover 9 has though holes 14. These holes can be large enough to allow the growing pots to pass the cover 9. The holes should be small enough to provide support to the 10 plants. Thus, plants are supported at their lower ends and near their upper ends. In order to prevent light from entering between the rim of the holes and the plant, a ‘light-lock’ 13 is provided which leaves only a small hole 10 (or may even completely locks). The light-lock should rest against the plant without damaging it, and provide an opening 10 adapted to the plant. In an embodiment the light-lock 13 comprises flexible sections or 15 flaps which together cover said through hole. In one embodiment, several circle sectors make from a rubbery material can be attached to the cover 9 as indicated. These sector parts can be provided with a soft rim. Furthermore, the sector parts at their radial edges can be interconnected by a flexible material. Figure 4 shows a cross section through a cover 9 with a light-lock 13 and the stem of a plant projecting through it. The sectors of 20 the light-lock rest flexibly against the stem without damaging it. The dotted line show an alternative, in which the light-lock is attached to the lower side of cover 9. In this embodiment, it may be easier to raise the cover 9. For leek, for instance, the lock should provide a passage of about 1-4 cm.

25 The light-lock 13 provides a diaphragm. The opening it provides can be adjusted, for instance by the pressure the plant passing the lock provides. The diaphragm has parts which can move with respect to one another, and have an end which can rest against the plant.

30 In operation, the system can be used in the following way. Seeds can be planted in the growing pots 6. Alternatively, a smaller first pot can be used, and the small plants can then be placed in the growing pots 6.

9

The growing pots 6 are positioned in trays. In the trays, the growing pots have are fixed positions. However, also in this stage several alternatives may be commercially interesting.

5 A first alternative is to position the growing pots at their end positions right from the start. A disadvantage of this approach is that it requires more space than absolutely necessary. An advantage is that the growing pots do not need to be repositioned.

Another alternative is to provide the growing pots at a first position, and to reposition 10 the growing pots during the growth. This process can be automated, and is used in the production of may crops, flowers and plants. It requires less space.

Once the plants are at their end positions and have reached a certain height, the cover 9 is placed. For this, several alternatives are possible. The first simple alternative is to 15 simply provide the cover, and allow (or help) the plants to pass the holes. In another alternative, the cover is provided at the height of the growing ports 9 at their end positions. The pots are passed through the cover 9. After the plants reach a certain height, the cover 9 is raised to a new height. In case of leek, the green leaves should pass the cover 9, but cover 9 should rest directly below the leaves, as indicated in figure 20 1.

It will be clear that the above description and drawings are included to illustrate some embodiments of the invention, and not to limit the scope of protection. Starting from this disclosure, many more embodiments will be evident to a skilled person which are 25 within the scope of protection and the essence of this invention and which are obvious combinations of prior art techniques and the disclosure of this patent.

Claims

A method for growing vegetables such as leeks or similar vegetables that have a portion that is not to be exposed to light, comprising the steps of: - providing vegetable plants at end positions on a tray; - providing water and nutrients to the vegetable plants; - providing a light-tight shield on a frame provided with through holes at the end positions for each vegetable plant, and allowing for each vegetable plant to pass the hole, the shield being provided at a first height relative to of the tray, and - increasing the height of the shield to follow the growth of the vegetable plants. 15

Method according to claim 1, further comprising the step of: - providing the vegetable plants in growing pots.

Method according to claims 1 or 2, further comprising the steps of: 20. placing the growing pots at a first position at a first mutual distance relative to each other on a tray; - repositioning the growing pots to end positions at a mutual end distance after a growth time, for increasing the mutual distance.

4. Method according to claims 1,2 or 3, wherein the growing pots are placed on another tray which is provided with the light-tight shield.

5. Method as claimed in one or more of the foregoing claims, wherein the height of the screening continuously follows the growth of the vegetable plants. 30

6. Method as claimed in one or more of the foregoing claims, wherein the shielding comprises a light-tight foil on a frame. 2001720

An assembly for growing vegetables such as leeks or similar vegetables that have a part that should not be exposed to light, comprising: - a tray for holding vegetable plants at an end position; - a light-tight shield on a shielding frame connected to the tray and provided with an actuator for adjusting a distance between the shield and the tray, the shield further being provided with through-holes in the end positions to enable a part of every vegetable plant can pass through it.

Assembly according to claim 7, further comprising: - a set of growing pots, a growing pot for each vegetable plant.

9. Assembly as claimed in claim 7 or 8, further comprising: - a frame on the tray, with retaining means for keeping the growth pots at end positions at a mutual distance.

An assembly according to claim 7, 8 or 9, wherein the tray is a water retaining tray, comprising an inlet for water and an outlet for water, for providing water to the vegetable plants. 20

11. Assembly as claimed in one or more of the foregoing claims 7-10, wherein the light-tight shield provides a plastic foil that can be reinforced, and is provided with a substantially black surface on the side facing the tray, and a substantially white surface on the opposite side. 25

12. Assembly as claimed in one or more of the foregoing claims 7-11, wherein the light-tight shield provides a plastic foil that can be reinforced, and is provided with through holes and a light lock with a variable opening, in one embodiment the light lock comprises flexible parts or flaps that together cover the 30 through holes.

An assembly according to claim 12, and comprising a set of growing pots, with a growing pot for each vegetable plant, wherein the growing pots have a shape and diameter, the continuous holes in the diameter and / or shape chosen to make it possible that the growth fit.

Assembly as claimed in one or more of the foregoing claims 7-13, wherein the S through holes in the shield are approximately 4-7 cm in cross section

15. Growth pot, for an assembly and method according to the preceding claims. 10-o-oo-o-o-2 00 1 72 0