GB2351895A

GB2351895A - Growing of greenhouse crops

Info

Publication number: GB2351895A
Application number: GB0013513A
Authority: GB
Inventors: John Piers Hopton Verey
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-06-12
Filing date: 2000-06-05
Publication date: 2001-01-17
Also published as: GB0013513D0; GB9913583D0

Abstract

A method of growing greenhouse crops, in particular tomatoes, involves the use of a greenhouse 6 erected in an area of a field, otherwise divided into a plurality of areas a, b, c, d, e. Crops are grown in the greenhouse for the first year, and subsequent to cropping, soil is removed from the greenhouse to a depth typically of 180mm - 225mm and deposited on one of the areas a of the field, the soil being spread over the area to a uniform depth. Soil is then removed from another area b and introduced into the greenhouse 6 and spread therein, similarly to a depth of 180mm - 225mm. A second crop is grown in the greenhouse, and subsequent to cropping, the soil is removed from the greenhouse and spread over one of the areas b and a fresh batch of soil is removed from a third area. In this way fresh soil is introduced into the greenhouse in successive years, and the quality of the soil removed from the greenhouse may be restored, conveniently by growing nitrogen-producing crops thereon.

Description

2351895

Title: Growing of Greenhouse Crops Description of Invention

This invention is concerned with improvements relating to the growing of greenhouse crops.

The invention has been devised particularly in relation to the growing of tomatoes, in which context the invention will hereinafter be described. It is however to be appreciated that the invention may be utilised in the growing of other fruit and vegetables, where similar or analogous problems arise.

Problems have been encountered for many years in the growing of tomatoes, particularly "cherry" tomatoes, where it is necessary that the growing takes place in a controlled environment, such as by use of a glass-house or greenhouse (hereinafter referred to generically as a greenhouse), particularly in the production of high quality tomatoes which may be sold at a premium price.

For a number of reasons it is desirable to grow the tomatoes in open soil, that is directly into the ground. In this way the plants will grow in the presence of naturally occurring nutrients, which produce tomatoes which have excellent flavour profiles. Additionally, the action of earthworms in the soil improves the root environment of the plants, increasing the resistance of the plant to root diseases, which would result in reduced production and/or inferior or malshaped fruit.

However repeated use of the same soil for the same crop causes crop decrease, and can render the system non-viable from a commercial point of view unless routine sterilisation takes place, either by chemical sterilisation, or by heat (steam) treatment.

Additionally the depletion of soil nutrients during growth of crops is produced, and although this can be remedied by the use of artificial fertilisers, this method of production is considered non-viable because of the high cost.

2 Whilst a solution to this problem could be seen in the utilisation of a small area, say 25%, of that enclosed by the greenhouse for the growing of a crop of tomatoes in one year, and by using a four year crop rotation cycle, this would be prohibitively costly, since it would be necessary to maintain an enclosed environment over an effectively non-productive area.

An alternative method of growing tomatoes in an enclosed environment is by the use of growing bags containing a growing medium such as peat. However three factors prevent this method from being successfully used in the growing of premium tomatoes on a commercial scale, as follows:

a) the high cost; b) it is necessary to use artificial nutrients such as soluble nitrate fertilisers, which reduces the quality of the flavour of the tomatoes; c) the absence of natural organisms in the growing bag can result in unfavourable conditions adjacent to the roots of the plant, increasing the tendency for root diseases to occur.

Additionally, from an environmental point of view, the use of peat is undesirable, and the disposal of the peat from the bags on completion of use is required.

For this reason for large scale commercial growing of tomatoes, soil-less growing systems (hydroponic systems) have been developed using spun mineral fibre (rockwool). Such a system has enabled yield increases of 40% over standard soil-grown systems. The main benefits are derived from maintaining an artificial but hygienic root environment, enabling 100% of the individual plants in the crop to be supplied with the correct rhizospheric air:water ratio necessary for a healthy root system. The improved visual product quality, earlier and higher yields, and reduction in labour costs of this system are highly beneficial.

However, there are certain problems in maintaining hydroponic systems:

3 a) it is necessary to use artificial fertilisers, such as Soluble Potassium Nitrate, which is believed to reduce the favour and healthgiving properties of the produce:

b) since the hydroponic environment is not suitable for soil-living fauna such as earthworms, and naturally occurring beneficial organisms which can protect against disease, the artificial environment can render crops more susceptible to disease, often requiring the application of artificial pesticides.

c) there is an environmental problem with the disposal of the growing substrates at the end of each season. Although the mineral fibre can, after steaming, be recycled, typically for three years, there is nonetheless eventually a large scale waste issue.

It is one of the various objects of this invention to provide a method of growing greenhouse crops in which some at least of the problems set out above may be reduced.

It is another of the various objects of this invention to provide a method of growing premium tomatoes on a commercial, and economically viable scale, whilst avoiding or reducing the need to utilise artificial fertilisers and pesticides.

According to this invention there is provided a method of growing vegetables or fruit involving the steps:

a) growing a crop in an area of ground enclosed by a greenhouse; b) on completion of growing and cropping, removing soil from the greenhouse; c) replacing the removed soil with fresh soil; and d) growing a further crop in the greenhouse, on the fresh soil.

For example it may be necessary to remove the soil to a depth of between 150 and 225 mm, typically 180 mm. In this manner the depleted soil is replaced with fresh, undepleted soil, allowing the further crop to be grown satisfactorily in open soil. Additionally the fresh soil is essentially disease free, 4 and the further crop may be grown with minimal risk of infection by soilpresent bacteria.

Preferably the removed soil is utilised for the growing of further plants or vegetables, although different from the crop, outside the greenhouse. Preferably the removed soil is utilised in the growing of nitrogenproducing plants or vegetables, such as clover or legumes.

According to this invention there is provided a method of growing crops in a greenhouse in which the crops are grown under organic conditions in the soil, and subsequent to cropping, the soil is removed from the greenhouse to a depth of between 150 and 225 mm, and replaced by fresh soil.

There will now begin detailed description, to be read with reference to the accompanying drawing, of a method of growing which a preferred embodiment of this invention, having been selected for the purposes of illustrating the invention by way of example.

The accompanying drawing is a schematic representation illustrating the invention. The method which has been selected to illustrate the invention by way of example is a method of growing cherry tomatoes, involving the use of a field of approximately 12 hectares. The field is divided into six sections, each of 2 hectares (20,000m 2), and in one section a greenhouse 6 is erected, having a construction, including doors, sufficient for use within the greenhouse of soilmoving equipment.

For the first year, soil is transferred into the greenhouse, to a depth typically of 180 mm, from an area A of the field. Tomatoes are grown in the soil within the greenhouse under normal organic conditions.

At the end of the growing period, and on completion of cropping, the soil is removed from the area enclosed by the greenhouse to a depth of, typically, 180 mm, and the soil is deposited on the area A of the field, the soil being spread over the area A to a uniform depth.

Soil is removed from an adjacent area B, similarly to a depth of 180 mm, and introduced into the greenhouse 6, and spread therein. The soil of the area B will be substantially disease free, and will not have been utilised for the growing of tomatoes for several years.

Upon completion of growing the second year crop in the greenhouse, the s11 f o rom the greenhouse is similarly removed and spread over the area B, and a fresh batch of soil is removed from the area C, and distributed within the greenhouse for the growing of a third year crop.

Duning this period, other fruit and vegetables may be grown on the areas A, B and C as may be desired, although of course it would be inappropriate to grow fruit or vegetables of the kind which are grown in the greenhouse.

For example for the first year clover may be grown on the area A, for ploughing in and returning to the soil natural nitrogen-containing nutrient. For the second and third year, if desired, legumes may be grown, similarly fixing nitrogen within the soil and producing a cash crop.

After completion of rotation, and removal of the soil from area E, soil from the area A may be returned to the greenhouse, for the growing of a further crop of tomatoes.

In this way, soil is utilised for the growing of the tomatoes which has not previously been used for tomatoes for five years, and in the meantime, has been brought back to a highly nutritious, substantially disease-free condition. If desired other commercial crops may be utilised, particularly in the stages D or E, provided that there is no incompatibility with the primary crop, with the objective of increasing soil fertility. To this end if desired the areas may also be utilised, in rotation, as pasture for livestock.

It will of course be appreciated that fewer than 5 areas may be utilised to provide the soil for the greenhouse (eg. 4), and the greenhouse itself need not be physically adjacent to the areas from which soil is derived.

6 Thus the invention involves the use of a sustainable, self-renewing system of growing greenhouse crops, which can be interfitted with a highly desirable crop rotation system.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

7 CLAIMS

I A method of growing vegetables or fruit involving the steps a) growing a crop in an area of ground enclosed by a greenhouse; b) on completion of growing and cropping, removing soil from the greenhouse; c) replacing the removed soil with fresh soil; and d) growing a further crop in the greenhouse, on fresh soil.

2 A method according to claim I wherein the dept of soil removed from greenhouse is between 150mm and 225mm.

3 A method according to one of claims I and 2 wherein the removed soil is utilised for the growing of further plants or vegetables outside the greenhouse.

4 A method according to claim 3 wherein the removed soil is utilised in the growing of nitrogen-producing plants or vegetables.

A method of growing crops in a greenhouse in which the crops are grown under organic conditions in the soil, and subsequent to cropping, the soil is removed from the greenhouse to a depth of between 150mm and 225mm, and replaced by fresh soil.

6 A method according to any one of the preceding claims involving the use of ground exterior to the greenhouse which is divided into a plurality of areas, and in which over successive years the soil removed from the greenhouse is spread over each area in turn, and fresh soil is returned to the greenhouse from each area in turn.

8 7 A method according to claim 6 involving the use of at least three such areas.

8 A method according to one of claims 6 and 7 involving the step of growing crops in each area on the soil thereof which has been removed from the greenhouse over successive years prior to returning the soil to the greenhouse.

9 A method according to any one of the preceding claims, in which the fruit or vegetables are tomatoes.

A method when carried out substantially as hereinbefore described with reference to the accompanying drawings.

11 Any novel feature or novel combination of features as hereinbefore described and/or shown in the accompanying drawings.