IE41840B1

IE41840B1 - Cultivation of plants growing singly in a spearate plant bed

Info

Publication number: IE41840B1
Application number: IE1791/75A
Authority: IE
Original assignee: Kosan As
Priority date: 1974-08-13
Filing date: 1975-08-12
Publication date: 1980-04-09
Also published as: JPS5749178B2; GB1523624A; NO752774L; AT341263B; ES440212A1; CH612822A5; FR2298934A1; FI54215B; FI752269A; NO138744C; IE41840L; BR7505150A; FR2298934B1; AU8389475A; JPS5145032A; NL7509553A; DD121007A5; AU501430B2; DK309575A; CA1021162A

Abstract

The method provides that in each case one seed kernel is sown in a cultivating bed, and the beds are situated closely together during the germination of the seed kernels. Thereafter, the beds are moved onto a conveyor belt (4) and pushed forwards in a cultivating channel (11). In the cultivating channel, the substances necessary for growth are supplied and drained at the base of the channel. The distance between the beds is enlarged in step with the increasing need of the plants for space during growth.

Description

This invention relates to the cultivation of plants growing singly in a separate plant bed, and in particular to a method for the cultivation of plants growing singly in a separate plant bed consisting for example of earth or cultivation blocks and having a cubic content sufficient to secure the plant, as well as to an apparatus comprising at least one cultivation channel with a conveyor belt for carrying out the method.

It is generally known to cultivate plants in oblong plant 10 boxes, which are supplied with water and nutritive salts to an appropriate constant level. The boxes may at the same time be placed on a step —like rack allowing the plants to grow upwards freely. By this known system, which is usually designated as water culture, there is achieved an improvement in the ordinary constant moisture cultivation of the bed. The disadvantage of the known water culture system is inter alia that it offers no possibility of an increase in the spacing between the plants in accordance with the growth of the plants, for which reason the system requires a large -341840 growing area per production unit.

In order to overcome this disadvantage it is known to piace the beds in a,holding stand which allows the spacing between the individual plants to be varied in accordance with their requirements. It is further known to place pots in a holding device for simultaneous raising and shifting of the pots in accordance with the growth of the plants and their consequent need for more space.

However, these known methods of increasing the distance between the plants in accordance with growth of the plants offer, no possibility for the simultaneous use of a known channel system for the supply of water and fertilizer solution, just as the known cultivation methods offer no substantial savings of labour or energy as a result of increased productivity and consequent reduction of the required growing area.

The present invention in one aspect provides a method for the cultivation of plants growing singly in a separate plant bed, wherein one seed is sown in each bed, which beds may be placed close together during the germination of the seeds, the beds being placed on one or several conveyor belts each situated in a respective cultivation channel where cultivation media are supplied to the plants and the excess drained off into the bottom of the channel, wherein the or each 43.840 -4conveyor belt supports the beds in the channel at a distance from each b.ther appropriate to the stage of development of the plants, and wherein the intervals between the individual beds are increased in accordance with the space required by the plants by increasing the intervals between the individual beds όη the or each conveyor belt and/or (1) transferring the beds from one set of channels to another set of channels spaced apart by a greater distance and/or increasing the intervals between the beds on adjacent channels or (2) increasing the intervals between the beds on adjacent sections of a channel, By the method according to the invention the supply of cultivation media, which continuously takes place in the channel or channels, may permit the plants to be fed very precisely, the ndtrient provided depending on the actual conditions of growth, and further the surplus cultivation media can be drained off into the bottom of the channel from beneath the beds and the root stocks. This ensures that harmful residues in the plants may be reduced by a hitherto unknown extent, flt the same time the value of the plants will be improved, since they assume a highly uniform quality. Moreover optimum utilization of the growing area is achieved, since each plant during its growth is at each stage of the treatment alloted the most suitable spacing. -541840 The invention in another aspect provides apparatus for carrying out the method according to the first aspect of the invention, comprising one or several conveyor belts each situated in a respective cultivation channel, means for supplying cultivation media to the cultivation channel or channels, and means for increasing the intervals between individual beds on the or each conveyor belt and/or (1) means for transferring the beds from one set of channels to another set of channels spaced apart by a greater distance and/or means for increasing the intervals between the beds on adjacent channels or (2) the spacing between the said channels or the sections of a channel increasing.

There may be suitably at least one channel and a conveyor belt, wherein the or each channel is substantially U-shaped in cross,-section with a bottom and sides, the sides being provided with a plurality of continuous ducts which are provided with a plurality of outlets towards the interior of the channel for the supply of cultivation media, guides being provided on each side for the conveyor belt which supports the beds, and the space between the belt and the bottom of the channel forming a drainage duct for the surplus liquid.

Preferably ducts for the supply of warm and cold water for regulation of the root temperature, and drains -6for the return of the surplus fluid are provided. A cover may be provided for limiting the evaporation from the beds and for preventing accumulation of condensation on the under side of the leaves. This protects the roots from the 1ight^prevents formation of algae, and is especially suitable for this form of cultivation.

The invention will be further described by way of example only, with reference to the accompanying Ιθ drawings, ih which:Figure 1 is a plan view of a cultivation system with straight and parallel channels; Figure 2 shows the cultivation system of Figure after the first picking; Figure 3 i.s a plan view of a cultivation system with straight channels in a fan pattern; Figure 4 is a schematic view of a cultivation system where the number of channels are reduced in accordance with the growth of the plants; Figure 5 shows schematically a continuous channel with loops which increase the distance between the plants; Figure 6 is a'sectional view of’a channel with a conveyor belt; Figure 7 is a sectional view of another embodiment of a conveyor belt; Figure 8 is a side view of the conveyor belt shown in Figure 7; -7Figure 9 is a sectional view of a further form of conveyor belt in its contracted position; Figure 10 is a sectional view of the conveyor belt shown in Figure 9 in its stretched position; Figure 11 is a section taken along the line XI-XI in Figure 10; Figure 12 is a sectional view of a further embodiment of a conveyor belt in its contracted position; Figure 13 is a sectional view of the conveyor belt shown in Figure 12 in its stretched position; Figure 14 is a plan view of a carrier in its turned-in position; Figure 15 is a plan view of the carrier shown in Figure 14 in its turned-out position; Figure 16 is a plan view of another carrier in its turned-out position; and Figure 17 is a plan view of the carrier shown in Figure 16 in its turned-in position.

Figure 1 shows a cultivation system for inter alia lettuce consisting of a number of parallel channels 11 which are situated for example in a hothouse. At the beginning of the production a number of cultivation blocks are placed on a conveyor belt 1-4, which blocks are watered at stage 1. The next stage is the sowing of one seed in each biock at 2, whereafter the blocks are conveyed for germination at stage 3. The blocks are placed on the conveyor belt a small distance -8apart, which in the case of lettuce cultivation is about 2 cm, and the blocks remain on the conveyor belt for between 10 and 14 days.

At stage 5 the blocks 21 are transferred to the next stage 6 of the system, as they are placed on a belt 20 in a channel, as shown in Figure 6. The intervals between the blocks may now be increased to twice the distance when on the conveyor belt, and a corresponding interval is maintained between the channels 11. in the channels are supplied the necessary cultivation media such as water and nutritive salts, as will be explained below in relation to the description of the channels.

After a suitable period at the nursing stage in the channels at stage 6, in the case of lettuce being 10 to 14 days, the plants are transported, for example via a conveyor belt 9, to.the next set of channels at stage 7, where the distance between the plants is four times the distance at stage 6.

When the plants have been growing for the same number of days as in the preceding stages the distance between the channels is increased by sideways shifting of the channels and belts to stage 8, which position is shown in Figure 2. Here the cultivation ends, since the plants after the same number of days as in -9the preceding stages are now, as far as lettuce is concerned, ready for picking, and the plants are now carried out of the channels by the conveyor belt to a traversing conveyor belt 10 for packing.

This cultivation method- proceeds continuously, new seeds being placed for germination on the conveyor belt as soon as the previous batch has been transferred in the channels at stage 6. When the channels are thus positioned as shown in Figure 2, young plants are transferred via the conveyor belt 9 from the stage 6 to the next channel system at stage 7. When the plants at stage 8 are picked as first mentioned, the channels are pushed together and shifted sideways and stage 7 plants as shown in Fig. 2 proceed onto stage 8 by shifting the channel sideways to the position shown in Figure 1.

A channel system where the plants may remain in the channel on the belt and thus need not be transferred to other channels is shown in Figure 3. The channels 11 are situated in the shape-of a fan such that each hothouse may accommodate two systems starting opposite each other at the nursing stage 6. The channels are stationary, whereas the belt may be provided with devices which increase the distance between the plants in accordance with their growth. Shifting the plants -loin the channel involves at the same time increasing the distance from the adjacent plants in the neighbouring channels.

Another channel system shown in Figure 4 consists of a number of channel sections 11 which hold the youhg plants at stage 6. By transfer of the plants to the next cultivation stage 7 the number of channels is reduced in a manner allowing simple spacing between neighbouring channels. In this way the system can be extended until it eventually ends in a single channel, after which the plants are adequately developed, I A cultivation system may be employed in which the channel 11 is unbroken, and the cultivation can consequently take place in a single channel as in the case of the fan pattern shown in Figure 3. The channel may be winding so that during the stages 6, 7 and 8 a suitable distance to the plant in the parallel channel section is maintained, as shown in Figure 5. Also conveyor belts with built-in devices for increasing the distance between the plants through the channel may be used.

In order to be able to utilize the method with the greatest possible advantage there may be employed a channel with a conveyor belt as shown in Figure 6.

The basic framework of the channel 11 is built as a -11U-shaped cross-section with a bottom 13 and sides 12. Instead of a U-shaped channel there may of course be employed other forms of channel, for example a channel made of a tube slotted longitudinally, which slot corresponds to the upper opening of the U-shaped channel.

In the sides and bottom of the channel are placed ducts 14, 15 and 17 running longitudinally along the channel. Further there are guides 18, 19 for a conveyor belt 20 movable along the channel. Between this belt 20 and the bottom of the channel 14 there is formed a duct . The belt 20 is provided with a clamp for securing a cultivation block 21 with a plant 22. The channel is dosed at the top by a pair of yielding lips 23, embracing the leaves of the plant but at the same time allowing movement of the belt with the plant along the channel.

The belt may be constructed such that nutritive fluid may be collected in the centre of the belt. Thus the root formation in the centre is accelerated, and the edges of the belt are initially kept free during the initial period of growth. This is to ensure that the roots of the plant approach each other and quickly form a continuous wick.

During the use of the channel for the supply of cultivation media, water and nutritive fluid may be supplied under -12pressure to the duct 15. This fluid is squirted through a number of outlets 16 into the cultivation blocks 21 in such quantities that fluid is continuously supplied to the plants. This direct supply through outlets will further ensure that fresh oxygen-containing nutritive fluid can be dosed evenly over the whole length of the channel, so that lack of oxygen is avoided. The belt 20 is provided with side walls, which are bent at the top towards the interior of the channel.

This ensures that a fluid reservoir 24 is formed in the belt, so that the roots of the plants may assimilate water and nourishiiient in this reservoir. The bent top edges further ensure that the roots are not to any particular extent growing out of the belt.

Moreover the root complex at the side will keep the plant firmly in the channel. The surplus fluid overflows the belt to pass into the bottom duct 25 of the channel, from where it is led to a reception tank, the duct; being inclined towards the reception tank, from which the surplus fluid is directed for reuse after for example analysis to ensure that the quantity of nutrient supplied is always correct. In the opposite duct 14 may be supplied carbon dioxide, which may slowly percolate up about the leaves, which will ensure an enconomical dosing.

As the plants need a certain constant root temperature -13there may be provided temperature regulating-media such as warm water in the lower ducts 17 in the bottom 13 of the channel.

There may be further ducts in the channel for example for the addition of hot or cold air, systemic poisons against plant dcsaases, algae-preventing media, growth retarding or flower inducing media, and root developers.

In case of the use ofsmall-sized blocks 21, the belt 20 may be elevated in the channel to slide on higher situated guides 19. This makes the return of the belt possible via the subjacent guide 18.

The closed construction of the channel with yielding lips 23 ensures that the channels have a high air humidity, which prevents choking of the outlets 16 by crystallizing nutritive salts. This will further reduce formation of condensation on the leaves and thus reduce attacks of fungi or diseases of the leaves. Moreover the light is prevented from entering the interior of the channel where-by the root growth is secured and algae formation is prevent as mentioned above. This will contribute further to meeting the oxygen and nourishment requirements of the roots.

Belts of a different construction as shown in Figures 7 and 8 may be employed, consisting of a flat central -14section 26 which along the sides is provided with longitudinal thickenings 27 to ensure the fluid reservoir 24. These thickenings may be made hollow, and this will provide ducts wh]ch inter alia may be available for a flow of cultivation media to achieve the correct growth In order to ensure the necessary increases of the spacing between the plants in a simple manner, a belt as shown in Figures 9 to 11 may be employed. A number of angled carrier sections 28 are connected together by a length of wire 29 such that the sections with the beds may be contracted during the nursing stage, as shown in Figure 9. By pulling the belt the distance is increased until the belt is tightened, as shown in Figure 10. When in this position the plants are fully developed.

A belt which offers the possibility of a considerable variation in the distances between the plants depending upon the pull is shown in Figures 12 and 13. The carrier sections 28 are connected by springs 30, which when untensioned keep the sections close together, as shown in Figure 12. Upon applying a pull the springs are tightened, and the distance may be regulated depending on the tractive force applied.

The beds can be conveyed by way of a carrier device as shown in Figures 14 and 15. The wire lengths 32 connect a number of coilers 31 constructed for coiling up the -15wire 32 when the wire 32 is not exposed to a pull, as shown in Figure 14. To each coiler 31 is attached an arm 33 which, when the wire is pulled in the direction indicated by the arrow whereby the coilers are turned, will swing out, as shown in Figure 15, and convey the individual beds in pots forwards in a direction towards the left of the drawing by means of which the distance between the individual beds is increased in conformity with the uncoiled section of the wire.

Finally, there may be employed a spring-loaded carrier arm 35, as shown in Figures 16 and 17 which is pivotally attached to a holder 34 which is in turn attached to a pulling wire 32 that may be resilient and yielding.

The arm 35 bears resiliently on a stop 36 in the turned-out position of the arm, as shown in Figure 16. When returning in the direction indicated by the arrow, towards the right in Figure 17, the is turning-in when passing the block 21, and then by a forward pull towards the left of Figure 16 swings out taking the plant 21 along. By increasing the length of wire between the individual holders 34 the distance between the adjacent beds 21 on the belt will be correspondingly increased.

As an example of the increase in production rendered possible by the cultivation system described above it may be mentioned that lettuce production, under Danish -162 conditions, may be increased to about 400 to 500 p/m growing area per year, compared with a traditional 2 production which amounts to about 150 to 200 p/m growing area per year.

The production period, i.e. the time from solving to 5 picking, may moreover be reduced by about one week compared with the length of time required by the traditional cultivation methods.

By automation of transport and transfers from one stage to the next and by an automatic guidance system for the supply of cultivation media in the channel and in the hothouse, the labour employed may be reduced by up to 90% compared with other known cultivation methods.

In addition there is achieved a highly uniform quality as a result of the totally identical conditions of growth offered to the plants during the individual stages of growth. Finally, as already mentioned, it is possible to produce plants in which harmful residual contents of nutrients have been reduced,as the system allows precise dosing depending on the actual conditions of growth. For example, the hitrate content in lettuce can be limited to 400 to 600 p.p.m. compared with the existing normal nitrate content of 6000 to 12000 p.p.m. Furthermore, the need for spraying against plant diseases is reduced, as the conditions favouring attack hy diseases are reduced.

Claims

WHAT WE CLAIM IS:

1. A method for the cultivation of plants growing singly in a separate plant bed, wherein one seed is sown in each bed, which beds may be placed close

2. A method as claimed in Claim 1 wherein a plurality of channels are each straight and the channels are 25 situated mutually parallel on the same level, and wherein the distance between the channels is adjusted by parallel shifting of the latter during part of the growth of the plants. - 18 41840

3. A method as claimed in Claim 1 wherein a plurality of channels are each straight and the channels are placed in a fan pattern on the same level with substantially the same mutual angles and close together

4. A method as claimed in Claim 1 wherein a plurality of channels are each straight and the channels are situated mutually parallel on the same level, and 5. Or each channel is substantially U-shaped in crosssection with a bottom and.sides, the sides being provided with a plurality of continuous ducts which are provided with a plurality of outlets towards the interior of the channel for the supply of cultivation

5. A method as claimed in Claim 1 wherein a channel 5 at one end of the channels where the beds are first placed on the conveyor belt. 5 together during the germination of the seeds, the beds being placed on one or several conveyor belts each situated in a respective cultivation channel where cultivation media are supplied to the plants and the excess drained off into the bottom of the

6. Apparatus for carrying out the method as claimed in Claim 1, comprising one or several cohveyor belts each situated in a respective cultivation channel, 20 means for supplying cultivation media to the cultivation channel or channels, and means for increasing the intervals between individual beds on the or each conveyor belt and/or (1) means for transferring the beds from one set of channels to another set of channels spaced apart by a greater distance and/or 25 means for increasing the intervals between the beds 19 41840 on adjacent channels or (2) the spacing between the said channels or the sections of a channel increasing.

7. Apparatus as claimed in Claim 6, comprising at least one channel and a conveyor belt, wherein the

8. Apparatus as claimed in Claim 7 wherein the

9. Apparatus as claimed in Claim 7 or 8 wherein the belt has a flat face and upstanding sides with 20 the top edges thereof bent towards the interior of the channel for formation of a fluid reservoir for the beds in the channel.

10. Apparatus as claimed in Claim 7 or 8 wherein the belt has a flat central part for supporting the 411840 20 beds with a longitudinal thickening at either lateral edge forming the sides of a fluid reservoir. 10 media, and with guides provided on each side for the conveyor belt which supports the beds, and wherein the space between the belt and the bottom of the channel forms a drainage duct for the surplus liquid. 10 wherein the distance between the channels is adjusted by a reduction in the number of channels as the beds from two or more belts are joined in a subsequent channel. 10 channel, wherein the or each conveyor belt supports the beds in the channel at a distance from each other appropriate to the stage of development of the plants, and wherein the intervals between the individual beds are increased in accordance with the space

11. Apparatus as claimed in Claim 7 or 8 wherein the belt consists of carrier sections connected to each other 5 hy a length or lengths of wire, corresponding to the distance between the carrier sections, one bed being placed on each carrier section.

12. Apparatus as claimed in Claim 7 or 8 wherein the belt consists of carrier sections connected to TO each other by means of a spring which in its untensioned state keeps the carrier sections together and which when subjected to a pull increases the distance between the carrier sections.

13. Apparatus as claimed in Claim 7 or 8 wherein

14. Apparatus as claimed in Claim 13 wherein the carriers consist of holders fixed at intervals to a -21wire and each of which is fitted with a pivotable carrier arm which by a spring device bears resiliently on a stop and against the elasticity of the spring device can be turned-in upon passage of the beds.

15. A method according to Claim 1 for the cultivation of plants growing singly in a separate plant bed, substantially as herein described with reference to Figures 1 and 2, Figure 3, Figure 4 or Figure 5 of the accompanying drawings. 15 carriers are used which consist of spring-tensioned coilers with carrier arms which, upon the pull of a connecting wire to unroll the wire of the coilers, turn-out the carrier arms so as to take the beds along the conveyor with a resulting increase in the 20 distance between the 'beds. 15 channel is closed at the top by a yielding cover slit at the top to permit passage and shifting of the plants in the channel. 15 is continuous and winding such that the distance between the individual loop sections is increased. 15 required by the plants by increasing the intervals between the individual beds on the or each conveyor belt and/or (1) transferring the beds from one set of channels to another set of channels spaced apart by a greater distance and/or increasing the intervals 20 between the beds on adjacent channels or (2) increasing the intervals between the beds on adjacent sections of a channel.

16. Apparatus according to Claim 6 substantially as herein described with reference to, and as shown in, Figure 6, Figures 7 and 8, Figures 9 to 11, Figures 12 and 13, Figures 14 and 15, or Figures 16 and 17 of the accompanying drawings.