JP2014100097A - Method for hydroponics, a polymer foam medium, and a hydroponic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a generation of waste by readily separating a root from a medium, to allow reuse of the medium by a low propagation of saprophyte or the like, and to readily form an air space for root respiration in relation to a hydroponics technology for cultivating a plant with a resin culture medium.SOLUTION: A container body 11 of a hydroponic device 10 contains a polymer foam 12 which has open cells and is cut into a contour having a size of 0.3 cm x 5.0 cm. A medium 13 is injected into a container body 11 to soak the polymer foam 12 and subsequently the medium 13 is discharged. A process where air spaces are formed between the polymer foams 12 while the medium is soaked in the open cells of the polymer foam 12 is repeatedly carried out.

Description

  The present invention relates to a hydroponic cultivation method, a polymer foam medium serving as a medium for the hydroponic cultivation method, and a hydroponic cultivation apparatus.

It is known to use rock wool, cocoon pattern, etc. for the culture medium of hydroponics. However, with rock wool, the roots of cultivated plants are entangled, and it is necessary to treat them as waste every time they are harvested. In addition, organic matter such as cocoon pattern has a problem that mold and other germs are easy to propagate, and quality varies depending on the production area.
On the other hand, a technique for growing using a culture solution without using such a medium has been developed. However, this technique has a problem of constructing a means for bringing the root into contact with air. With regard to this problem, for example, Japanese Patent No. 2743342 (Patent Document 1) describes a technique for positively mixing air into a nutrient solution.

Japanese Patent No. 2741342

  However, the technique described in Patent Document 1 is a technique for mixing air into a nutrient solution using a mixer, and the equipment becomes complicated. In addition, there is a limit to the amount of air that can be dissolved in the nutrient solution, and an optimum amount of air cannot always be obtained.

  Therefore, the present invention has been made to solve the disadvantages in the case of using the above-mentioned conventional culture medium, and it is easy to separate the root and the culture medium after harvesting and can drastically reduce the generation of waste. An object of the present invention is to provide a medium structure that can be used repeatedly and has good profitability, and can provide a medium structure in which an air layer can be easily obtained and respiration from the roots can be activated.

  In order to achieve the above object, a hydroponics method for growing a plant on a resin medium contains a plurality of polymer foams having open cells and cut to a size of 0.3 cm to 5.0 cm at random. After injecting the culture liquid into the main body and immersing the polymer foam, repeating the process of injecting and discharging the culture liquid to discharge the culture liquid from the container main body, and into the open cell of the polymer foam And a step of forming a gap between the polymer foams for growing and growing plant roots. A hydroponic cultivation method is provided.

Since the polymer foam is used as the medium, mold and other bacteria are difficult to propagate and the quality is constant. Since the outer shape is cut to a size of 0.3 cm to 5.0 cm, a flat surface is easily formed on the surface of the polymer foam, and a large number of polymer foams are randomly accommodated in the container body. In certain cases, a predetermined gap is likely to occur. Therefore, it is possible to obtain a gap in which the roots of the plant extend, and it is possible to form voids suitable for root growth, contact with air, and contact with the culture solution.
Furthermore, since it is a size of 0.3 cm to 5.0 cm, it can be easily separated from the roots, and the polymer foam can be easily removed from the roots of the harvested crops. Such polymer foams can be mixed in various sizes within a range of 0.3 cm to 5.0 cm.

To inject the culture solution into the container body, immerse the polymer foam, discharge the culture solution, soak the culture solution into the bubbles of the polymer foam, and form a gap between the polymer foams Plants can be grown by growing roots in the voids.
Since the polymer foam has open cells, when the culture solution is poured into the container body and the polymer foam is immersed in the culture solution, the culture solution can be infiltrated into the bubbles. Thereafter, even if the culture solution is discharged from the container body, the culture solution can be held in the bubbles by capillary action. And since a culture solution is hold | maintained in a polymer foam, if this polymer foam is pressed, a culture solution can ooze out to the space | gap between polymer foams.

  The polymeric foam can be made from polyurethane, polystyrene, polyethylene, or polypropylene. Since the material of the polymer foam is polyurethane, polystyrene, polyethylene, or polypropylene, it is relatively hydrophobic and the surface tension of the polymer foam surface can be kept high. Therefore, it is easy to keep the culture solution in the open cell of the polymer foam.

The shape of the polymer foam can be a hexahedron or a tetrahedron. Since the shape of the polymer foam is a hexahedron or a tetrahedron, when a plurality of polymer foams are randomly accommodated in the container body, a gap suitable for root growth can be formed. In particular, since the surface of the hexahedron or tetrahedron is formed as a flat surface, it is easier to generate voids suitable for root growth than when formed as a curved surface. Furthermore, by using a large sheet-like polymer foam as a raw material, and then cutting it into a hexahedron or a tetrahedron, a polymer foam of a desired size can be obtained without generating wasteful waste material. .
If an appropriate gap can be generated between the polymer foams, a polyhedron other than a hexahedron or a tetrahedron, a square, or a spherical body can be used. The polymer foam accommodated in the container body can be used by mixing polymer foams having different shapes.

  Also, a nutrient solution comprising a polymer foam medium comprising a plurality of polymer foams having open cells and cut to a size of 0.3 cm to 5.0 cm, and a container body containing the polymer foam medium In the cultivation apparatus, injecting the culture liquid into the container body, immersing the polymer foam, and then injecting and discharging the culture liquid from the container body, A plurality of polymer foams were randomly accommodated in the container body so as to form a space between the polymer foams for replenishing the culture solution into open cells and growing plant roots to grow. A hydroponic cultivation apparatus for forming a polymer foam medium is provided.

  This hydroponic cultivation apparatus includes a polymer foam medium composed of a plurality of polymer foams having open cells and cut to a size of 0.3 cm to 5.0 cm, and a container body. Since the polymer foam having a size and shape is randomly stored in the container body, the culture medium is replenished into the open cells of the polymer foam by injecting and discharging the culture medium into the container body. On the other hand, voids necessary for the growth of plant roots can be formed between the polymer foams. Therefore, plants can be grown without causing root rot.

  By randomly storing a plurality of polymer foams cut to a size of 0.3 cm to 5.0 cm in the container body, the volume of the portion other than the polymer foam in the container body, that is, in the container body The porosity can be 40% to 65%. Since the void ratio in the container body is 40% to 65%, voids necessary for the growth of plant roots can be appropriately formed.

  Moreover, it is a polymer foam medium in which a plurality of polymer foams having open cells and cut to a size of 0.3 cm to 5.0 cm are randomly stacked, and in the container body for hydroponics The space for replenishing and growing the roots of the plant by replenishing the culture solution into the open cells of the polymer foam by injecting the culture solution into the container body and discharging the culture solution from the container body Provided is a polymer foam medium that can be formed between polymer foams.

  A polymer foam medium in which a plurality of polymer foams having open cells and cut to a size of 0.3 cm to 5.0 cm are randomly stacked, accommodated in a container body for hydroponics, By injecting the culture liquid into the container body and discharging the culture liquid from the container body, the culture liquid is replenished into the open cells of the polymer foam, and the voids for growing the roots of the plant to grow are polymer foamed. Because it is a polymer foam medium that can be formed between bodies, it is possible to form a space suitable for root growth, contact with root air, and contact with root culture solution. It is suitable as a medium for liquid culture.

According to the hydroponic cultivation method and polymer foam medium of the present invention, and the hydroponic cultivation apparatus, a space suitable for the growth of plant roots can be formed, and the roots can be brought into contact with air or a culture solution. Plants with excellent quality can be grown.
Moreover, according to the hydroponic cultivation method, the polymer foam culture medium, and the hydroponic culture apparatus of the present invention, the polymer foam can be easily removed from the roots, can be reused, and is not easily discarded.

It is the schematic of the hydroponic cultivation apparatus which can perform the hydroponic cultivation method of this invention.

The present invention will be described in more detail based on embodiments.
FIG. 1 is a schematic view of a hydroponic cultivation apparatus 10 that performs the hydroponic cultivation method of the present invention. The hydroponic cultivation apparatus 10 includes a container body 11, a polymer foam (medium) 12, a panel 14, and a siphon pipe 16. It is composed of The container main body 11 contains a medium made of the polymer foam 12, and the polymer foam 12 is impregnated with the culture solution 13. A panel 14 serving as a lid of the container body 11 is provided with a seedling base 15 on which a plant to be grown is rooted. A siphon pipe 16 is installed in the container body 11 so that the culture solution 13 can be discharged.
Each part which comprises such a hydroponic cultivation apparatus 10 is demonstrated further in detail.

(Polymer foam medium)
A predetermined polymer foam 12 is used as the medium. The material is a resin from which a porous foam can be obtained, and examples thereof include polyurethane resin and polystyrene resin. However, the material may be a foam made of one raw material, or a foam made of a plurality of raw materials. May be mixed. Among these resins, a flexible urethane foam made of a polyurethane resin and having a continuous air bubble and being soft and recoverable is preferable.
Thus, the polymer foam 12 is a foam in which open cells are formed instead of closed cells in order to allow the culture solution to enter the bubbles and to exude water from the bubbles. However, it is not intended to exclude the presence of closed cells.

Properties possessed by the polymeric foam 12 is 10kg ^{/ m 3} ~100kg ^/ m 3 in apparent density. Moreover, the hardness is 60N-700N by the test result in the large-sized polymer foam before cutting by JISK6400-2 (D method). Since the polymer foam 12 has such physical properties, it is not too hard or too soft, and when a large number of polymer foams 12 are randomly accommodated in the container body 11, the weight of the polymer is maintained by holding the culture solution 13. The corners of the foam 12 are slightly crushed. As a result, even the polymer foam 12 positioned on the upper side of the container main body 11 by capillary action due to the continuous bubbles of the polymer foams 12 communicating with each other can be filled with the culture solution 13.

The shape of the polymer foam 12 is rectangular, and can be a hexahedron or a tetrahedron.
The hexahedron is preferable in that a small hexahedron can be cut out from a large thick plate-like foam sheet and can be easily formed. Further, the tetrahedron is preferable in that the foamed sheet can be cut out without wasting it.

The size of the polymer foam 12 is 0.3 cm to 5.0 cm in outer shape, and in the case of a hexahedron, the length of one side is 0.3 cm to 5.0 cm. If it is smaller than 0.3 cm, the gap between the polymer foams becomes small and it is not sufficient for root growth. In addition, the root becomes entangled with the polymer foam, making it difficult to reuse the medium. Moreover, when larger than 5.0 cm, the space | gap between polymer foams will become large and root growth will worsen.
The size in the case of a tetrahedron is preferably set to a size similar to the size of this hexahedron.

(Culture medium)
As the culture solution 13, a culture solution containing an appropriate amount of components such as nitrogen and phosphorus suitable for the target plant to be grown can be used. From the standpoint of preventing the occurrence of mold, etc., a culture solution mixed with inorganic fertilizer is preferred.

(Cultivation container)
The cultivation container is most simply a container composed of a container body 11 having a depth that opens upward and a panel (mounting material) 14 placed on the open portion of the container body 11. 11 can accommodate the polymer foam 12 and the culture solution 13.
Various materials such as resin, metal, and ceramic can be used as the material of the container body 11. In order to prevent the generation of algae in the container body 11, the container body 11 is preferably light-shielding.
Moreover, the shape is not particularly limited, and a box shape (cuboid shape) is preferable from the viewpoint of efficient arrangement of the hydroponic cultivation apparatus 10, but other shapes such as a column shape may be used.
The depth of the container body 11 can be appropriately changed depending on how the roots of the plants to be grown are stretched, and is relatively deep when growing a plant having roots extending long downwards, not only downward but also laterally. If the roots are extended and do not extend so long below, they can be made relatively shallow. In general, in the case of lettuce or the like, it is a preferable mode to be 10 cm to 30 cm.

  The volume of the portion other than the polymer foam 12 in the container body 11, that is, the porosity in the container body 11, is obtained by subtracting the apparent volume × number of the polymer foam 12 from the volume of the container body 11. The value obtained by dividing the value by the volume of the container body 11 is preferably 40% to 65%. This is to appropriately form voids necessary for plant root growth.

The panel 14 functions as a lid of the container body 11 and serves as a base on which the seedling 18 is placed. Since it is a lid | cover, it plays the role which interrupts | blocks the incident light in the container main body 11, and generation | occurrence | production of algae can be suppressed.
Resin, metal, or the like can be used as the material of the panel 14, but resin is preferable from the viewpoint of lightness. Suitable resins include polystyrene resins, polyolefin resins (eg, polypropylene resins, polyethylene resins), polyester resins (eg, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate), polycarbonate resins, polylactic acid Based resins and the like. Among these resins, polystyrene or a composite resin containing polystyrene and polyethylene is preferable from the viewpoint of lightness and ease of handling. In addition, it is more preferable in terms of lightness that these resin panels are foams.

In the present embodiment, the panel 14 is provided with a recess 14a serving as a mounting portion on which the seedling base 15 is placed at predetermined intervals, and a through hole 14b penetrating the panel 14 is formed in the central portion of the recess 14a. . The seedling 18 can be installed by placing the growing seedling base 15 provided with the seedling 18 of the plant to be grown on a solid medium such as a foam in the recess 14a.
The panel 14 is made of a light shielding material so that light from the outside does not enter the inside of the container body 11, or a light shielding film is provided on the surface of the panel 14 to make it light shielding. good.

(Siphon pipe)
It is necessary to repeatedly inject and discharge the culture solution 13 into the container body 11 filled with the polymer foam 12. The culture solution 13 can be discharged by a culture solution discharge means such as a siphon pipe 16.
As shown in FIG. 1, the siphon pipe 16 is arranged such that one end 16 a of the pipe is arranged close to the bottom surface 11 a inside the container main body 11, and the other end 16 b is outside the container main body 11 and below the one end 16 a. The horizontal portion 16c is placed below the water level at which the container body 11 is full. When the siphon pipe 16 is provided, the culture solution 13 can be naturally discharged from the container body 11 filled with the culture solution 13 and the water level can be reduced to the opening of the one end 16a. Thereby, the excess culture solution 13 can be removed from the container main body 11. Of course, the device is not limited to the siphon pipe 16, and any device that can discharge the culture solution 13 when the culture solution 13 is supplied and reaches a certain volume in the container body 11 may be used.

(Cultivation method)
First, the polymer foam 12 cut into a predetermined size is put in the container body 11, and the polymer foam 12 is packed up to the opening edge of the container body 11. The reason why the polymer foam 12 is packed to such a height is to bring the roots from the seedlings 18 placed on the panel 14 into contact with the polymer foam 12. The polymer foam 12 can be prefilled with the culture solution 13 before being put into the container body 11.
On the other hand, a seedling base 15 having a seedling 18 of the growing plant has taken root is prepared. The seedling raising base 15 is obtained by germinating or planting a seedling 18 on a foam base to establish a seedling. The seedling base 15 is placed in a recess 14 a provided in the panel 14 and stabilized in the panel 14.
The culture medium 13 is put into the container body 11 from a hole (not shown) or the like provided in the panel 14. The culture solution 13 injected into the container body 11 is also impregnated into the bubbles of the polymer foam 12. Here, it is preferable that the culture solution 13 is infiltrated into the polymer foam 12 by crushing the polymer foam 12 in advance in a nutrient solution to release the air in the polymer foam 12.

  After filling the container body 11 with the culture solution 13, the culture solution 13 is discharged from the container body 11. This discharge is performed by the siphon pipe 16. The culture liquid 13 injected into the container main body 11 enters the polymer foam 12 and its water surface rises in the container main body 11. At this time, the siphon pipe 16 also enters the siphon pipe 16 from one end 16a. The culture solution 13 enters and the water level in the siphon pipe 16 also rises. Then, when the culture solution is injected until the water level rises past the horizontal portion 16 c of the siphon pipe 16, the culture solution 13 is naturally discharged from the other end 16 b of the siphon pipe 16 to the outside of the container body 11. This discharge is continued until the water surface falls to the position of the one end 16a of the siphon pipe 16.

By discharging the excess culture solution 13 in this way, the polymer foam 12 is exposed to form a gap between the polymer foams 12, and the polymer foams 12 are appropriately pressed and come into contact with each other. Bubbles communicate with each other, and the culture solution 13 can be stored in the polymer foam 12.
By repeating a series of cycles in which the culture solution 13 is injected into and discharged from the container body 11 at appropriate time intervals, the culture solution 13 that is absorbed or evaporated by the plant and decreases from within the polymer foam 12 is obtained. The polymer foam 12 is replenished, and voids can be formed between the polymer foams 12. Although the repetition interval depends on the degree of root growth, temperature, humidity, and other environments, for example, in the cultivation of lettuce or the like, it is preferable to perform it at a frequency of every 2 hours.

According to this hydroponic cultivation apparatus 10, since there is a gap between the polymer foams 12, the root of the plant to be grown can be extended into this gap. And this root is not immersed in water and does not cause root rot. Further, the root that contacts the polymer foam 12 grows by absorbing the culture solution 13 filled in the open cells of the polymer foam 12. The polymer foam 12 filled with the culture solution 13 prevents roots from drying.
The grown plant can be easily separated without being entangled in the polymer foam 12 when it is removed from the panel 14. Therefore, the harvested plant can be easily harvested, and if the new seedling base 15 is placed on the panel 14, it can be easily transferred to the next plant.

Such embodiment is an example of this invention, is not limited to this, It includes the other arbitrary modified forms which are not contrary to the meaning of this invention.
As an example, for example, when the polymer foam 12 is filled in the container body 11, a net is put on the container body 11 in advance, and the polymer foam 12 can be put in the net. . When the polymer foam 12 is taken out, such as when cleaning the container body 11 or the polymer foam 12, it is only necessary to take out the entire net, and the trouble of taking out the polymer foam 12 one by one can be saved.
Further, the polymer foam medium may be mixed with a medium such as soil, stone, or other inorganic substances to the extent that does not hinder root growth.

  As the polymer foam 12 filled in the container body 11, polymer foams 12 having different properties on the upper side and the lower side of the container body 11 can be used. As an example, the upper side of the container body 11 is filled with the soft polymer foam 12 and the lower side is filled with the hard polymer foam 12. Since the polymer foam 12 containing the culture solution 13 also increases in weight, the lower polymer foam 12 that is subjected to a large load in the container body 11 is hardened to be crushed and is not so large. By making the upper polymer foam 12 soft, it can be easily crushed. By doing so, the collapsing degree of the contact part of the polymer foams 12 can be made comparable on the upper side and the lower side in the container main body 11. Thus, the same degree of gap can be generated on the upper side and the lower side of the container body 11.

  As another example, the upper side of the container body 11 is filled with the polymer foam 12 having a large bubble rate, and the lower side is filled with the polymer foam 12 having a small bubble rate. Then, since the upper polymer foam 12 contains a large amount of the culture solution 13 and becomes heavier than the lower polymer foam 12, the upper and lower sides in the container body 11 are similar to the above example. Thus, the degree of collapse of the contact portions between the polymer foams 12 can be made the same level. Thus, the same degree of gap can be generated on the upper side and the lower side of the container body 11.

  The placement on the seedling base 15 on the panel 14 is an example of cultivation from a young seedling. Therefore, it is possible not to use the raising seedling base 15. For example, the panel 14 itself may be formed of a soft porous material and seeded on the panel 14 so that the roots are directly taken out from the panel. The panel 14 is sufficient if it places a growing plant and allows its roots to come out below.

  The injection method for putting the culture solution 13 into the container body 11 and the discharge method for discharging the culture solution 13 from the container body 11 can be changed. What is necessary is just to have a process and the process of discharging | emitting a culture solution to the bottom face 11a vicinity of a container main body. For example, without using the siphon pipe 16, a discharge port may be provided on the bottom surface 11 a of the container body 11, and only the culture solution 13 may be discharged therefrom.

(1) Preparation of culture solution After dissolving 1.5 g of Otsuka House No. 1 (trade name) manufactured by Otsuka Agritechno Co., Ltd. per liter of water, 1.0 g of Otsuka House No. 2 (trade name: company) Dissolved to make a culture solution.

(2) Preparation and Pretreatment of Polymer Foam Two types of polymer foams having different types of foam as described below were prepared and used as Sample 1 and Sample 2.
[Sample 1] 80SH made of a cube having a side of 0.5 cm (Sekisui Urethane Co., Ltd. (trade name), density 80 kg / m ³ , porosity 52.4%)
[Sample 2] 16M20 / 5 consisting of a cube with one side of 0.5 cm (Sekisui Urethane (trade name), porosity 55.4%)
The urethane foams of Sample 1 and Sample 2 were thoroughly swollen in the culture medium, and the air inside was replaced with the culture liquid.

(3) Germination of mustard and preparation of nursery seeds Mustard seeds were soaked in water for one day, and then embedded in a urethane foam for sowing soaked with a culture solution, and placed in a light place for 3 days to germinate.
After germination, it was grown under an LED unit manufactured by CCS (light intensity: 130 μmol / m ² / s for 10 days).

(4) Set of hydroponic cultivation apparatus It put into the plastic container main body so that the urethane foam filled with the culture solution might be spread, and the polymer foam culture medium was accommodated in the container main body.
On the other hand, a hydroponic panel (mounting material) having mounting portions at intervals of 10 cm was prepared, and seedlings of mustard were set on the mounting portion together with the urethane foam for sowing. And this hydroponic panel was set so that the opening part of a container main body might be covered.
The container body is provided with siphon-type culture solution discharge means for injecting the culture solution and automatically discharging the culture solution out of the container body when a certain volume is reached.
In such a hydroponic cultivation apparatus, two kinds of urethane foams to be accommodated were prepared as Sample 1 and Sample 2, and seedlings were cultivated with each of the hydroponic cultivation apparatuses.

(5) Supply of culture solution The culture solution was supplied at a frequency of once every 2 hours. Moreover, the culture solution was poured into the container body to fill the container body. After filling up, the culture solution was automatically discharged by a siphon type culture solution discharge means.
(6) Cultivation conditions Light (light intensity: 130 μmol / m ² / s) was supplied to the seedlings by the LED unit during cultivation in the hydroponic cultivation apparatus. The ambient temperature is 24 ° C (± 2 ° C) during the daytime (6am to 6pm), 20 ° C (± 2 ° C) at night (6pm to 6am), and the humidity is 70% (± 5%). It was adjusted.

(7) Cultivation results The weight of the edible part from which the roots on the 30th day of cultivation were removed was 40.4 g and 39.39 respectively with mustard grown in a hydroponic cultivation apparatus using the polymer foams of Sample 1 and Sample 2. It was 7 g.

  The polymer foam 12, the hydroponic cultivation apparatus 10, and the hydroponic cultivation method using the hydroponic cultivation apparatus 10 are suitable for cultivation of leafy vegetables such as lettuce, which are mainly called leaves, but the roots grow large. It can also be applied to the cultivation of plants called things.

DESCRIPTION OF SYMBOLS 10 Hydroponic cultivation apparatus 11 Container main body 11a Bottom surface 12 Polymer foam 13 Culture liquid 14 Panel 14a Recessed part 14b Through hole 15 Seedling base 16 Siphon pipe 16a One end 16b The other end 17 Liquid pool 18 Seedling

Claims (8)

In the hydroponics method of growing plants in resin medium,
After injecting the culture solution into a container main body containing a plurality of polymer foams that have open cells and cut to a size of 0.3 cm to 5.0 cm, and soak the polymer foam, this culture solution Repeat the process of injecting and discharging the culture solution from the container body to replenish the culture solution into the open cells of the polymer foam, and the void to grow the plant roots And a step of forming between the foams.   The hydroponics method according to claim 1, wherein the polymer foam is polyurethane, polystyrene, polyethylene, or polypropylene.   The hydroponic cultivation method according to claim 1 or 2, wherein the polymer foam is a hexahedron or a tetrahedron. Hydroponic cultivation apparatus comprising a polymer foam medium composed of a plurality of polymer foams having open cells and cut to a size of 0.3 cm to 5.0 cm, and a container body containing the polymer foam medium Because
Injecting and draining the culture liquid into the container body, immersing the polymer foam, and then discharging the culture liquid from the container body. A polymer foam medium containing a plurality of polymer foams in a container body at random so as to form a space between the polymer foams for growing plant roots and growing them. Hydroponic cultivation device to form.   The hydroponic cultivation apparatus according to claim 4, wherein the porosity in the container body is 40% to 65%.   When the culture medium injected into the container body reaches a certain volume, the culture medium discharge means for discharging the culture liquid to the outside of the container body, and a mounting portion for covering the opening of the container body and mounting the plant The hydroponic cultivation apparatus according to claim 4 or 5, comprising a mounting material.   A polymer foam medium in which a plurality of polymer foams having open cells and cut to a size of 0.3 cm to 5.0 cm are randomly stacked and contained in a container body for hydroponics , By injecting the culture liquid into the container body and discharging the culture liquid from the container body, the medium is replenished into the open cells of the polymer foam and the voids for growing plant roots are grown A polymer foam medium that can be formed between foams.   The polymer foam medium according to claim 7, wherein the porosity is 40% to 65%.

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