Hydroponic systems, uses of such systems, and methods for germinating seeds and growing shoots, seedlings, and plants

Abstract

The present invention relates to a hydroponic cultivation system for germinating seeds and growing them into plants. The hydroponic cultivation system includes a container having a receiving space. The system further includes a first wall element dividing the receiving space into a lower section arranged to receive a gas and an upper section arranged to receive a liquid. The first wall element has a first opening, allowing gas-liquid communication between the lower and upper sections. The system further includes a connection arrangement arranged to connect a gas pressure device to the lower section. The system further includes a support member arranged to maintain the seeds and plants at a predetermined distance above the first wall element and substantially parallel to the first wall element. The support member has a second opening to allow humidification of the seeds and roots, through which the roots grow. The system further includes a cover device arranged to separate the hydroponic cultivation system from its upper side. The cover device encloses the container and the support member. The present invention further relates to the use of such a hydroponic cultivation system and to a method for germinating seeds and growing them into plants.

Description

[Technical Field]

[0001] The present invention relates to a hydroponic cultivation system for the germination of seeds and the growth of sprouts, seedlings and plants.The present invention further relates to the use of such a system for the hydroponic germination of seeds and the growth of sprouts, seedlings and plants.The present invention further relates to a method for the germination of seeds and the growth of sprouts, seedlings and plants. [Background technology]

[0002] Hydroponics is a type of horticulture that involves starting or growing plants without soil, by using water or aqueous mineral nutrient solutions.

[0003] Today, there are many types of hydroponic systems. In all systems, overall plant growth is understood to consist of two distinct cycles: the germination cycle and the growth cycle. In the germination cycle, the seed sprouts and develops the first roots and stems (the stems are essentially colorless or very pale because they have not yet been exposed to light and therefore have not produced chlorophyll). The shoots then develop into seedlings (seedlings are typically green (e.g., red in the case of beetroot seedlings) because they have been exposed to light and therefore produce chlorophyll). Seedlings are also called microgreens. In the growth cycle, the shoots develop into seedlings, which then develop into mature plants. The mature plants can be flowering and / or fruit-bearing plants.

[0004] Most hydroponic systems require plants or at least sprouts in their growing cycle: seeds are first germinated separately in a different system, a so-called seedbed, and then transplanted into the actual hydroponic system where the plants or sprouts can grow.

[0005] An example of this is the Nutrient Film Technique (NFT). See, for example, GB 1245581. After germination and sufficient growth, plants are placed in a nutrient-rich water channel, where a very shallow stream of water containing dissolved nutrients (a nutrient film) is recirculated past the bare roots of the plants, resulting in the development of a thick root mat. Other examples include deep water culture, in which plant roots are continuously submerged in nutrient-containing water, and ebb and flow systems, in which plant roots are submerged in water only a few times a day. Thus, these systems require external input, such as manual or automated changes to the environment or setup, to transplant sprouts or plants grown in another system into a hydroponic system.

[0006] Additionally, hydroponic systems may use solid media in addition to water. Rockwool is the most widely used media in hydroponics. Examples of other media used are wood fiber, sheep wool, coconut coir, rice husk, perlite, vermiculite, pumice, sand, and gravel. As such, these systems require materials to be used up, removed, discarded, or processed for recycling. Furthermore, the use, removal, disposal, and / or recycling of solid media involves additional manual or automated operations.

[0007] To avoid growing plants in water that is easily contaminated, stagnant, or reused, an improvement to the aforementioned example of a hydroponic system is the use of air bubbles to oxygenate the water to promote growth. See, for example, WO2020100193. The main drawback of this improvement is that it still requires plants, or at least sprouts, to be transplanted into the hydroponic system from another system where the original seeds were germinated.

[0008] On the other hand, US 4057930A describes an apparatus for germinating seeds for cultivating sprouts (Figures 5, 8 and 11 of US '930), a so-called seedbed, which comprises a seed support screen mounted at a predetermined distance above a water reservoir in which an aerator grid is immersed, providing a circulating flow of water droplets and moist air around and through the screen.

[0009] In view of the above, it is believed that new and more advanced hydroponic systems, uses of such systems, and new methods for germinating seeds and growing them into plants are highly desirable. In particular, there is a clear need in the art for hydroponic systems, uses of such systems, and methods for germinating seeds and growing them into plants that can be used or adapted to germinate seeds and grow them into plants. Summary of the Invention [Problem to be solved by the invention]

[0010] The primary object of the present invention is to provide an improved hydroponic system, use of such a system, and method for germinating seeds and growing plants to produce strong, lush, nutritious, healthy shoots, seedlings, and plants.

[0011] A further object of the present invention is to provide a hydroponic system that is economical to use as it requires less maintenance, thus saving maintenance, repair and replacement costs. [Means for solving the problem]

[0012] In a first aspect, the present invention relates to a hydroponic cultivation system for germinating seeds and growing plants. The hydroponic cultivation system includes a container having a receiving space. The hydroponic cultivation system further includes a first wall element dividing the receiving space into a lower section configured to receive a gas and an upper section configured to receive a liquid. The first wall element has a first opening, allowing gas-liquid communication between the lower and upper sections. The system further includes a connection arrangement arranged to connect a gas pressure device to the lower section. The system further includes a support member arranged to maintain the seeds and plants at a predetermined distance above the first wall element and substantially parallel to the first wall element. The support member has a second opening to allow humidification of the seeds and roots, through which the roots grow. The system further includes a cover device arranged to separate the hydroponic cultivation system from its upper side. The cover device surrounds the container and the support member.

[0013] In a second aspect, the present invention relates to the use of a hydroponic cultivation system according to any one of the preceding claims for the hydroponic germination of seeds and the growth of seeds into plants.

[0014] In a third aspect, the present invention relates to a method for germinating seeds and growing them into plants. The method includes providing a liquid to an upper section of a receiving space of a hydroponic cultivation system according to the first aspect. The method further includes providing pressurized gas to a lower section via a connection arrangement and a gas pressure device. The method further includes providing seeds, seedlings, and / or plants on a support member. The method further includes maintaining the support member at a predetermined distance above the liquid. The support member includes a second opening for allowing roots to grow through the second opening and for allowing humid air to reach the seeds, seedlings, and / or plants.

[0015] Any embodiment applicable to the first aspect of the present invention is correspondingly applicable to the second and third aspects of the present invention.

[0016] At least one of the above-mentioned objects is achieved by a hydroponic cultivation system according to the present invention.

[0017] Without wishing to be bound by theory, the inventors believe that the method of the present invention results in the formation of bubbles in the liquid and their bursting at the surface, providing moist air between the liquid and the support member holding the seeds, seedlings, and / or plants, allowing the seeds and seedlings to be in a moist environment and / or humidify the seeds and / or roots without the need for roots to reach the water, thereby enabling seed germination and initial root growth. Depending on the distance between the support member and the liquid, the bubbles may first contact the support member before bursting. Once the roots reach the liquid, they are well-oxygenated as air passes through the liquid, and plant growth continues in the same system. Furthermore, the bursting of the bubbles allows for good circulation of humid air, allowing optimal flow of oxygen and nutrients to reach the seeds and / or roots. Further advantages of the system of the present invention are described below.

[0018] The present invention will now be described with reference to the accompanying drawings, in which embodiments of the invention are shown and in which like reference numerals indicate the same or similar elements. [Brief explanation of the drawings]

[0019] [Figure 1] 1 illustrates, in cross section, an example of a hydroponic system for germinating seeds and growing them into plants according to the present invention, including a cover device that allows for continuous germination and sprouting of seeds in a closed environment. [Figure 2] FIG. 1 shows a second example of a hydroponic system for germinating seeds and growing them into plants according to the present invention in cross section, after the cover device has been removed to allow space for the plants to grow after germination and / or to develop flowers and / or fruits and to give the plants access to light. [Figure 3]1 shows a third example of a hydroponic system for germinating seeds and growing plants according to the present invention in cross section, where the system holds seeds, sprouts, seedlings, and plants with flowers and fruit, illustrating that the system can be used for seeds and plants in various growth cycles simultaneously, and for growth during successive cycles over time. [Figure 4a)-b)] 1 shows a fourth example of a hydroponic system for germinating seeds and growing them into plants according to the present invention in cross section, in which the distance between the support member and the first wall element is adjustable (from a) to b) or vice versa). The distance is adjusted before the system is put into use. However, those skilled in the art will understand that the distance can be adjusted during a growing cycle. [Figure 5] 5 shows a fifth example of a hydroponic system for germinating seeds and growing them into plants according to the invention in a cross-sectional view, in which the second wall element is present and provides partial coverage of the receiving space on the upper side, even when the cover device is removed. [Figure 6] 1 shows a perspective view of a second example of a hydroponic system for germinating seeds and growing them into plants according to the present invention. [Figure 7] Three different types of microgreens are shown, grown from top to bottom, using a traditional ebb and flow hydroponic system, on a hemp mat solid medium, a coco mat solid medium, and a hydroponic system according to the present invention (no solid medium). [Figure 8a)-b)] Root growth through a support member is shown, where seeds were grown in a conventional ebb and flow hydroponic system using a palm mat solid medium (a) and in a hydroponic system according to the present invention (b) without a solid medium. DETAILED DESCRIPTION OF THE INVENTION

[0020] FIG. 1 shows a cross-section of a container 1 comprising a receiving space 2 , a first wall element 3 dividing the receiving space 2 into a lower section 4 and an upper section 5 .

[0021] The lower section 4 holds a gas, e.g., air, and the upper section 5 holds a liquid, e.g., water, which may be rich in nutrients such as minerals.

[0022] The first wall element 3 is provided with first openings 6 that allow gas to migrate from the lower section 4 to the liquid in the upper section 5, thereby generating bubbles in the liquid. The openings 6 can be uniformly distributed within the first wall element 3, generating bubbles throughout the entire wall element 3. The first openings 6 are, for example, 0.1 to 1 mm in size. The size of the openings 6 affects the formation of bubbles in terms of the rate of bubble formation and the size of the bubbles. The properties of the liquid, particularly the surface tension and viscosity, as well as the properties of the gas, can also affect the characteristics of the bubble formation.

[0023] The lower section 4 has an opening 7, which is a connection arrangement arranged for connecting a gas pressure device (not shown) to the lower section 4. The gas pressure device (not shown) is for adding pressurized gas to the lower section 4. When gas is added to the lower section 4, the gas flows through the first opening 6 and forms bubbles in the liquid held in the upper section 5. The gas pressure maintained within the lower section 4 prevents the liquid from flowing into the lower section 4 through the first opening 6. The diameter of the first opening 6 is preferably selected so that the surface tension of the liquid prevents the liquid from flowing through the first opening 6. Under these conditions, two-phase flow, in which the liquid and air can expand in opposite directions beyond each other, does not occur. The gas pressure within the lower section 4 affects the rate and uniformity of bubble formation.

[0024] There is a support member 8 arranged to maintain the seed or plant at a predetermined distance above the first wall element 3 and substantially parallel to it.

[0025] When the bubbles reach the surface of the liquid, they burst, generating microdroplets in the space between the liquid and the support member 8. In one example, the bubbles may reach a certain size before bursting and may first contact the support member 8. This space holds a gas, such as ambient air. When the bubbles burst at the surface of the liquid, a current is created in the air above them, keeping the humidified air in constant motion. The amount of humidification and air current generated depends on the size of the bubbles and the speed at which they burst.

[0026] The support member 8 has a second opening 9 to allow humidification of the seeds and roots and to allow the roots to grow through the second opening 9. For example, the support member 8 can be a mesh tray. The size of the second opening 9 must be large enough to allow at least moist air to reach the seeds, but not so large that the seeds fall through the opening 9. The roots of the seeds must be able to grow through the opening 9. The distance between the liquid surface and the support member 8 affects the degree of humidification and the amount of moisture in the form of microdroplets that reaches the seeds and roots. This distance must be large enough to allow the formation and bursting of bubbles. The expected distance between the liquid surface and the support member 8 is between 0.1 and 7 cm, for example, between 0.2 and 5 cm, or more specifically, between 0.5 and 2 cm.

[0027] The liquid level can also affect the coalescence of bubbles before they reach the liquid surface, which leads to the formation and bursting of larger bubbles at the liquid surface. The liquid level is also a contributing factor to the degree of liquid flow, which can affect the precision of where bubbles form, coalesce, or burst.

[0028] Additionally, there is a cover device 10 that defines the boundary of the hydroponic cultivation system from above and encloses the support member 8 together with the container 1. The cover device 10 shown in FIG. 1 is a lid. It creates a closed environment that maintains humidified gas (air) within the system. Another function of the cover device 10 is to provide a dark cover that limits the space above the seeds and / or provides a downward force, thus providing resistance to seeds trying to push back, helping the seeds shed their seed coats and promoting the growth of stronger stems, and simulating the presence of soil over the seeds. The cover device 10 can be removed to allow the user access to the system. Another reason for removing the cover device 10 is to allow space for the plants to grow after germination and to allow the sprouts, seedlings, or plants to receive light.

[0029] Figure 2 shows another example of a hydroponic cultivation system according to the present invention. This system is very similar to the system of Figure 1, and the diagrammatic explanations provided with respect to Figure 1 also apply to Figure 2, with the following exceptions: Figure 2 differs from Figure 1 in that the cover device 10 is not depicted. Removal of the cover device 10 allows space for the sprouts, seedlings, or plants to grow after germination, allows space for the plants to develop flowers and / or fruits, and allows light to be provided to the plants.

[0030] Figure 3 shows another example of a hydroponic system according to the present invention. This system is very similar to the system of Figure 2, and the diagrammatic explanations provided with respect to Figure 2 also apply to Figure 3, with the following exceptions: Figure 3 differs from Figure 2 in that the system holds seeds, sprouts, seedlings, and plants with flowers and / or fruit, indicating that the system can be used for growth during successive cycles over time, as well as for seeds and plants in different growth cycles simultaneously.

[0031] Figures 4A and B show another example of a hydroponic cultivation system according to the present invention. This system is very similar to the system of Figures 1-3, and the diagrammatic explanations provided with respect to Figures 1-3 also apply to Figures 4A and B, with the following exceptions: Figures 4A and B differ from Figures 1-3 in that the distance between the support member 8 and the first wall element 3 is adjustable (from A to B or vice versa). This distance is adjusted before the system is put into use; however, those skilled in the art will understand that this distance can also be adjusted during a growth cycle.

[0032] FIG. 5 shows another example of a hydroponic cultivation system according to the present invention. This system is very similar to the system of FIG. 1, and the diagrammatic explanations provided with respect to FIG. 1 also apply to FIG. 5, with the following exceptions. FIG. 5 differs from FIG. 1 in that the upper section 5 includes a second wall element 11 at a predetermined distance from and substantially parallel to the first wall element 3 to receive the support member 8. As can be seen from FIG. 5, in this example, the support member 8 is sized smaller than the width of the container 1 at its upper side. The second wall element 11, together with the cover device 10, covers the receiving space 2 of the container 1 at its upper side. The presence of the second wall element 11 provides a partial cover of the receiving space 2 at its upper side even when the cover device 10 is removed. The second wall element 11 and the support member 8 can be connected to each other and can be removable from the container 1. Although the cover device 10 in Figure 1 covers the entire top surface of the container 1 and is supported by the container 1, it is also conceivable that the cover device 10 is supported by a second wall element 11 and only provides a cover for the support member 8, as in Figure 5.

[0033] Figure 6 shows an example of a hydroponic system according to the present invention in a perspective view. This system is very similar to the system of Figures 1-5, and the diagrammatic descriptions provided with respect to Figures 1-5 also apply to Figure 6, with the following exceptions. The perspective view of the hydroponic system according to the present invention reveals ribs 12 that can be used to strengthen the lower section 4, thereby preventing the lower section 4 from deforming under pressure, for example by using ribs to connect the bottom of the container 1 and the first wall element 3. Those skilled in the art will understand that various materials can be used for such ribs 12, such as fiberglass or plastic.

[0034] FIG. 7 shows three different types of microgreens, grown from top to bottom using a traditional ebb and flow hydroponic system, on a hemp mat solid medium, a palm mat solid medium, and a hydroponic system according to the present invention (without solid medium), respectively.

[0035] Figures 8A and B show root growth through the support member, where seeds were grown using a traditional ebb-and-flow hydroponic system, using a palm mat solid medium (A), and using a hydroponic system according to the present invention (without solid medium) (B).

[0036] As mentioned above, in a first aspect, the present invention relates to a hydroponic system for germinating seeds and growing seedlings and plants. In other words, the system is suitable for the entire growth cycle of plants, including germinating seeds to produce sprouts, developing the sprouts into seedlings (microgreens), developing the seedlings into plants, and cultivating the plants until they reach maturity, for example, until they flower or fruit, and / or until they are ready to be harvested.

[0037] The object of the present invention is to provide a hydroponic cultivation system in which seeds, growing seedlings, and / or plants to be germinated are suspended at a predetermined distance above a liquid, and a gas is supplied to the liquid to form bubbles on the surface of the liquid, which burst to create a moist environment above the liquid. The bursting bubbles disperse small droplets of water, allowing the seeds, and the seedlings and / or plants (roots) to obtain the water and nutrients necessary for germination and growth. As a result, the hydroponic cultivation system can be used both for seed germination and for growing plants from the seeds, without the need to pre-germinate the seeds in a separate seedbed.

[0038] In an embodiment of the first aspect of the invention, the first openings 6 are uniformly distributed over the entire surface of the first wall element 3. The diameter of the first openings 6 is preferably selected so that the surface tension of the liquid does not allow the liquid to flow through the first openings 6. Under these conditions, two-phase flow, in which the liquid and the air could expand in opposite directions over one another, does not occur. Furthermore, the gas pressure maintained in the lower section 4 prevents the liquid from flowing into the lower section 4 through the first openings 6.

[0039] Those skilled in the art will understand that the distance between the first openings 6 can vary and that this affects the size of the bubbles and whether the bubbles coalesce. The inventors have discovered that the highest germination rates can be obtained when the distance between the first holes allows the bubbles to reach a certain size without coalescing, and therefore reach the support member 8 before bursting. Those skilled in the art will understand that the generation of bubbles allows for oxygenation of the liquid, which is beneficial for germination, healthy roots, and increased nutrient uptake.

[0040] A further advantage of the system, which comprises a receiving space 2 divided into a lower section 4 and an upper section 5 by a first wall element 3, the lower section 4 being arranged to receive a gas and the upper section 5 being arranged to receive a liquid, the first wall element 3 being provided with a first opening 6, allowing gas and liquid communication between the lower section 4 and the upper section 5, is the ease of cleaning and maintenance of the first wall element 3. For example, algae, bacteria, and lime deposits are particularly easily removed through the first opening 6. In a particular embodiment, the predetermined distance between the first wall element 3 and the support member 8 is between 1.1 and 7 cm. In a more particular embodiment, the predetermined distance is between 1.1 and 5 cm. In an even more particular embodiment, the predetermined distance is between 1.5 and 3 cm.

[0041] In another embodiment of the first aspect, the second openings 9 are uniformly distributed over the surface of the support member 8. In a particular embodiment, the support member 8 is a mesh tray.

[0042] The above configuration allows for uniform formation and distribution of foam, as well as optimal use of the available surface of the first wall element 3 for foam generation, and therefore of the available surface of the liquid, resulting in a high yield and successful germination of germinated seeds, grown seedlings, and / or plants. The efficient humidification achieved by the above arrangement also leads to a reduction in the amount of liquid required. The above arrangement therefore allows for economical use of (scarce) water, nutrients, and other components of the liquid. Furthermore, the above arrangement allows for seed germination and seedling or plant growth without the need for a solid medium.

[0043] In another embodiment of the first aspect, the cover device 10 is movable to allow access to the support member 8 in a first position of the movable cover device 10 and block access to the support member 8 in a second position of the movable cover device 10. "Access" in this context refers to access by a user of the system. The cover device 10 can form a closed system in the second position, thereby accumulating and maintaining moisture within the system. Another function of the cover device 10 can be to provide a dark cover that closes the space above the seeds and / or provides a downward force, thus providing resistance to seeds trying to push back, helping the seeds shed their seed coats and promoting the growth of stronger stems, and simulating the presence of soil over the seeds. The cover device 10 can be placed in the first position to allow a user to access the system. Another reason can be to provide additional space for sprouts, seedlings, and / or plants to grow after germination and to allow the sprouts, seedlings, and / or plants to receive light.

[0044] The movable cover device 10 therefore allows further optimization of the combination of seed germination and plant and seedling growth within one system, allowing for sequential germination of seeds in a closed environment and growth of seedlings and plants in an open environment.

[0045] In another embodiment, the upper section 5 comprises a second wall element 11 at a distance from and substantially parallel to the first wall element 3 for receiving the support member 8 .

[0046] In a further embodiment of the first aspect, the upper section 5 comprises a second wall element 11 at a predetermined distance from and substantially parallel to the first wall element 3 for receiving the support member 8. In one embodiment, the predetermined distance between the first wall element 3 and the second wall element 11 is between 1 and 7 cm. The second wall element 11 allows for further control of the environment within the upper section 5 and thus allows for optimised humidification of the seeds, seedlings and / or plants.

[0047] In a further embodiment of the first aspect, the system comprises an adjusting device for adapting a predetermined distance between the support member 8 and the first wall element 3 and / or between the second wall element 11 and the first wall element 3. An adjusting device for adapting a predetermined distance between the seeds, seedlings and / or plants and the liquid allows for optimization of the humidification of the seeds.

[0048] In a further embodiment of the first aspect, the hydroponic cultivation system further comprises a gas pressure device for generating pressurized gas, the gas pressure device being communicatively coupled to the connection device 7 for supplying the pressurized gas to the lower section 4 via the connection device 7. The gas pressure device may be any that allows the pressurized gas to flow into the lower section 4. field

[0049] Those skilled in the art will understand that the embodiment of the first aspect of the hydroponic cultivation system of the present invention can be made of an opaque material to block light. It is well known that some types of seeds prefer or require darkness to germinate, while other types of seeds require or prefer exposure to light. Furthermore, an advantage of using an opaque material is that blocking light can prevent the formation of algae.

[0050] As mentioned above, the present invention relates in a second aspect to the use of a hydroponic system according to any one of the preceding claims for the hydroponic germination of seeds and the growth of seeds into plants.

[0051] As mentioned above, the present invention relates in a third aspect to a method for germinating seeds and growing the seeds into plants.

[0052] In one embodiment of the third aspect, the method further comprises the step of enclosing the support member 8 together with the container 1 by means of a cover device 10, which delimits the receiving space 2 on its upper side.

[0053] In a further embodiment of the third aspect, the method further comprises adjusting the predetermined distance between the support member 8 and the liquid by means of an adjustment device. The predetermined distance between the support member 8 and the liquid can be adjusted prior to germination and growth to optimize the system for particular types of seeds, sprouts, seedlings, and / or plants.

[0054] In a further embodiment of the third aspect, the liquid is or comprises water. The liquid can comprise nutrients (organic or inorganic), such as essential, variable, and non-essential macro- and micronutrients (e.g., nitrogen, potassium, phosphorus, calcium, magnesium, cobalt, and minerals). In certain embodiments, the liquid is water containing nutrients. Furthermore, the pH of the liquid can be altered to achieve an optimal setting for a particular type of seed, sprout, seedling, or plant.

[0055] In a further embodiment of the third aspect, the distance between the surface of the liquid and the support member 8 is between 0.1 and 7 cm, preferably between 0.2 and 5 cm, more preferably between 0.5 and 2 cm. The optimum distance depends on the size of the bubbles upon bursting and the desired amount of humidification.

[0056] In a further embodiment of the third aspect, the pressurized gas flow through the first opening 6 provides a supply of single and / or coalesced bubbles that burst at the liquid surface. Coalescence generates larger bubbles that burst at the liquid surface, resulting in different amounts and rates of humidification. In some applications, little or no coalescence may be desirable. In other applications, coalescence of bubbles before bursting may be preferred. The amount of coalescence is affected by, among other things, the diameter of the first opening 6 or the level and nature of the liquid present in the upper section 5 of the container 1. Those skilled in the art will understand that the rate of humidification depends, at least in part, on the rate at which bubbles are generated, which in turn depends, at least in part, on the gas pressure.

[0057] In a further embodiment of the third aspect, the pressure buildup in the lower section 4 is achieved by a flow of pressurized gas through 90-100% of the first openings 6. In one embodiment, the difference between the size (perforation diameter) of the first openings 6 and the volume of the lower section 4 of the vessel 1 makes it possible to maintain a static pressure buildup in the lower section 4 and provide a uniform gas distribution through said openings.

[0058] Compared to the system of US4057930A, the hydroponic system of the present invention allows for efficient humidification of seeds, resulting in improved germination rates and yields. Furthermore, the amount of water required is reduced. Furthermore, the system is low maintenance and easy to clean.

[0059] The hydroponic cultivation system disclosed in US 4,057,930A is intended for use as a seedbed, as evidenced, inter alia, by the fact that the system includes a water heater to maintain temperatures within a range of 68°F to 92°F (20°C to 33°C), which typically can lead to bacterial and fungal overgrowth if the system is used beyond the cultivation of seedlings. The system described in US 4,057,930A includes an aerator grid positioned above the water, which includes a tubular member. The use of the tubular member results in uneven and suboptimal perforation distribution along only a portion of the water's surface area, resulting in uneven and suboptimal humidification of the germinating seeds. Furthermore, the tubes create resistance to airflow within the tubes, causing friction and turbulence, which creates pressure drops along the tubes and results in uneven and suboptimal humidification of the germinating seeds. Furthermore, because the aerator grid is positioned above the water, this system requires significantly more water than other systems, primarily due to the use of the aerator grid. Furthermore, because the aerator grid is placed on top of the water, the lower layer of water is not agitated. This has the disadvantage that the stagnant water layer promotes the growth of algae and bacteria. These algae and bacteria do not remain in the water layer below the aerator grid but quickly move to the upper layer. This may also require more frequent water changes. Such aerator grids also require regular cleaning, maintenance, and possibly even repair or replacement.

[0060] Other variations of the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Reference signs in the claims shall not be construed as limiting the scope thereof.

[0061] The scope of the present invention is defined by the appended claims. One or more of the objects of the present invention are achieved by the appended claims. [Example]

[0062] The present invention will be further explained by the following examples, which are merely illustrative and are not to be considered as limiting the invention.

[0063] Example 1 Materials and Methods Setting parameters An in-house experiment was conducted using a hydroponic cultivation system according to the present invention (hereinafter referred to as "HS"), which had the following parameters: - distance between the bottom of the container (1) and the first wall element (3): 9 mm - distance between the first wall element (3) and the second wall element (11): 36 mm - distance between the first wall element (3) and the support member (8): 19 mm - Support member (8); size of second opening (9) (unless otherwise specified): 1.5 mm x 1.5 mm - Liquid level: 18mm - first wall element (3); diameter of first opening (6): 0.6 mm - Air pressure: 2.3 PSI - Distance between support (8) and cover device (10): 40 mm

[0064] growth space The HS system was placed in a sealed growth chamber for the duration of the germination and growth cycle.

[0065] The growth space contained air temperature and humidity, which were monitored daily using an SHT31-D temperature and humidity sensor. Within the growth space, air humidity was monitored at a constant level of approximately 85%, and temperature was measured at a constant level of 22°C. For illumination, a single full-spectrum 24W Barrina T8 growth light was installed 30 cm above the system and was turned on from day 4 during the transition period from the germination cycle to the growth cycle.

[0066] microgreens Red radish (Raphanus sativus) "Sango" was used throughout the experiment.

[0067] irrigation According to the invention, irrigation was achieved by bursting bubbles on the surface of the liquid placed in the upper section (5) of the receiving space (2). Air was introduced into the system for 20 minutes to cause the bubbles to burst, and then stopped for 40 minutes. This procedure was repeated throughout the entire experiment (both germination and growth cycles) from sowing to harvest.

[0068] Tap water was used for irrigation for the first three days, with an average pH of 7.8 and water hardness of 230 ppm.

[0069] Fertilization Four days after sowing, essential micro- and macronutrients were added to the existing water in the system. The nutrient solution contained the essential micro- and macronutrients: Terra Aquatica TriPart Original FloraGro 3-1-6. The fertilizer solution was obtained by mixing 1 ml of FloraGro per 1 liter of water. The fertilizer solution measured 560 ppm (700 scale) and a pH of 6.

[0070] During the transition period from the germination cycle to the growth cycle of the hydroponic cultivation system (HS) according to the present invention, the cover device (10) was removed to provide the germinated sprouts with light and space for further growth.

[0071] Calculating germination rate On day 8, the germination rate was calculated as follows: Germination rate (%) = number of germinated seeds / number of seeds planted x 100 Seed density = seeds sown (g) / 1m 2

[0072] Microgreens in different positions on the tray (8) were measured with a ruler from the base of the stem to the tip of the seedling. Similarly, microgreens with roots were measured with a ruler from the tip of the seedling (microgreen) to the tip of the root. Finally, the length of the first leaf (cotyledon) of the microgreens was measured by measuring the length of the larger of the two cotyledons of each microgreen.

[0073] Fresh weight yield calculation Microgreens were harvested by cutting the seedlings at the base of the stem (lower hypocotyl portion). Microgreens harvested from each cultivation cycle were weighed to determine fresh weight yield.

[0074] result Humidification as a function of parameters Ha: Distance between the liquid surface and the support member (8) Hw: Liquid level d: diameter of the first opening (6) LP: Low pressure maintained in the lower section (4): 0.8 PSI HP: High pressure maintained in the lower section (4): 1.8 PSI Initial (starting) humidity 55% System temperature 20.8°C The humidity was measured on the support (8). [Table 1]

[0075] The results showed, among other findings, that applying high pressure to the lower section (4) reached a higher overall humidity in 5 minutes compared to the lower pressure case. At both low and high pressures, the highest humidity reached in 5 minutes was when the diameter of the first opening (6) was 0.6 mm, the liquid level was 50 mm, and the distance between the liquid level and the support member (8) was 10 mm.

[0076] Regarding the time to reach 85% humidity (from an initial humidity of 55%), the shortest time to reach such humidity was recorded when the diameter of the first opening (6) was 0.6 mm and the liquid level (Hw) was 50 mm for both low and high pressure in the lower section (4).

[0077] When the diameter of the first opening (6) is 1 mm, the shortest time to reach 85% humidity is recorded for both the liquid level height (Hw) of 10 mm and 50 mm.

[0078] Germination rate and fresh weight yield in relation to liquid level [Table 2]

[0079] The results showed that the optimal liquid level for the selected system parameters was 15 mm and 20 mm. The inventors found that in the systems used in these examples, when the liquid level was below 10 mm, there was insufficient water and time for bubbles to form and coalesce. Very small bubbles simply burst, and the small droplets did not reach the seeds, failing to generate humid air. On the other hand, when the liquid level was above 25 mm, bubble formation and coalescence became very active, resulting in agitation within the liquid and bubbles coalescing and bursting in unexpected places. The seeds initially sown evenly on the support (8) did not have uniform access to the ideal environment (irrigation).

[0080] Example 2 Effect of seed density on fresh weight yield Three HS setups were prepared and treated according to Example 1, except that a total of six different seed densities were sown and tested. The average results obtained are shown below. result [Table 3]

[0081] The results show that the relationship between seed density and the obtained fresh weight yield increases almost linearly. Therefore, the higher the seed density (342.32 g / m), the higher the yield. 2 ), resulting in higher harvest fresh weight yields at the seed densities tested.

[0082] The tested samples were free of fungal infection and had a yield of 342.32 g / m 2 No root rot was observed even at a seeding density of 1000. The inventors believe these results are partly related to the absence of a solid medium, which contains (stagnant) water that can lead to the development of such diseases. The absence of a solid medium provides additional space for the sown seeds to germinate and grow, and also promotes further air movement by constantly moving moist air with the bursting of bubbles.

[0083] Example 3 Comparative experiment using a hose system An HS setup was prepared and handled according to Example 1. An embodiment of the present invention was compared with a similar system in which a serpentine tube (hereinafter referred to as "ST") was used to supply air instead of the lower section (4) for bubble generation in and at the liquid surface and oxygenation of the liquid. Therefore, in this comparative system (ST), the first wall (3) was not present. The parameters of the serpentine tube used in the comparative example were as follows: - Outer diameter: 9mm - Inner diameter: 6mm - Material: Vinyl

[0084] The diameter of the perforations along the canal and the distance between perforations were similar to those in HS.

[0085] For ST, similar to HS, air was introduced into the system for 20 minutes to cause bubble bursting, followed by a 40-minute pause. This procedure was repeated throughout the entire experiment (both germination and growth cycles) from sowing to harvest.

[0086] result [Table 4]

[0087] The results show that at all seed densities tested, the system according to the invention (HS) had significantly higher germination rates and fresh weight yields than the system using the serpentine pipe (ST). Throughout the experiments, it was observed that the further away the perforations in the serpentine pipe (ST) were from the source of pressurized air, the lower the amount of foam (lower efficiency). Therefore, the efficiency in the total surface area of ​​the receiving space was not met as in the HS.

[0088] Example 4 Comparison experiments between hydroponic cultivation techniques (and culture media) The HS setup was prepared and handled according to Example 1. For comparison, a traditional hydroponic cultivation technique, an ebb and flow hydroponic system, was set up. This technique involves placing a cultivation tray above a liquid reservoir. Two types of cultivation media were used for this technique: palm matting and hemp matting (hereafter referred to as "CM" and "HM," respectively). Seeds were sown directly into these media.

[0089] The CM and HM (Eb and Flow system) were placed in the seedbed during the germination cycle and in a closed cultivation space during the growth cycle.

[0090] In these hydroponic systems, trays were pressure-spray irrigated twice daily from the top of the tray during the germination cycle, then returned to the seedbed. During the growth cycle, the trays were placed in an enclosed growing space. Following traditional ebb-and-flow irrigation methods, a pump pumped water (nutrient solution) into the top tray, which then returned the solution to the reservoir. This process was repeated six times over a 24-hour period. This allowed the medium (coconut and hemp mats) to be periodically cleaned with water and air.

[0091] In the HS setup, tap water was used for irrigation for the first 3 days, with an average pH of 7.8 and a water hardness concentration of 230 ppm. Four days after sowing, essential micro- and macronutrients were added to the existing water in the ebb and flow system. The fertilizer solution was prepared by mixing 1 ml of FloraGro with 1 L of water. The fertilizer solution measured 560 ppm (700 scale) and a pH of 6.

[0092] The dimensions of the mesh trays used in both CM and HM were similar to those in HS: 34 cm × 25 cm × 3 cm, except that no medium was placed on top of the trays in HS, whereas a 10 mm thick palm mat and a 10 mm thick hemp mat were placed on top of the Ebb and Flow system trays (CM and HM, respectively).

[0093] All trays were manually seeded on the tray surface with 9.25 g of seeds per tray (unless otherwise stated), resulting in a seed density of 158.15 g / m 2 is equivalent to

[0094] Microgreens were harvested by cutting the seedlings at the base of the stem. Red radish (Raphanus sativus) "Sango" was used throughout the experiment.

[0095] result [Table 5]

[0096] These results indicate that the germination rate, fresh weight yield, average stem height, and average leaf length increased in the HS setup compared to the traditional ebb-and-flow setup, even when different cultivation media (CM and HM) were used.

[0097] Example 5 Comparative experiments between hydroponic techniques (and growing media) for different seed densities Three HS setups, three CM setups, and three HM setups were prepared and treated according to Examples 1 and 4, except that a total of six different seed densities were tested in each system (HS, CM, HM). The average values ​​obtained are shown below.

[0098] result [Table 6]

[0099] The results show that germination rate remains constant with increasing seed density in HS, but decreases with increasing seed density in CM and HM.

[0100] Again, the inventors believe that these results are due to the optimally maintained ideal conditions (high humidity and constant circulation of moist air due to bursting bubbles) that allow the seeds planted in the hydroponic system of the present invention to germinate properly.

[0101] The results are shown in the seed density (g / m 2 ) versus fresh weight yield (g / m 2 The increase in the tensile strength of the HS embodiment is steeper than that of the CM and HM embodiments, reaching 256.74 g / m 2 The results show that the slope becomes even steeper from seed density of . [Explanation of symbols]

[0102] 1 container 2 Reception space 3 First Wall Element 4 Lower Section 5 Upper Section 6 First opening 7 Connection Configuration 8 Support member 9 Second opening 10 Cover device 11 Second Wall Element 12 Ribs

Claims

1. 1. A hydroponic cultivation system for germinating seeds and growing plants, comprising: a container (1) comprising a receiving space (2), a first wall element (3) dividing said receiving space (2) into a lower section (4) arranged to receive a gas and an upper section (5) arranged to receive a liquid, said first wall element (3) comprising a first opening (6) allowing gas-liquid communication between said lower section (4) and said upper section (5); a connection arrangement (7) arranged to connect a gas pressure device to said lower section (4); a support element (8) arranged above said first wall element (3) for maintaining seeds and plants at a predetermined distance substantially parallel to said first wall element (3), said support element (8) comprising second openings (9) for allowing humidification of the seeds and roots, the roots growing through said second openings (9); a cover device (10) arranged to delimit the hydroponic system on its upper side and to enclose the support member (8) together with the container (1); A hydroponic cultivation system comprising:

2. 2. The hydroponic system according to claim 1, wherein the first openings (6) are uniformly distributed over the first wall element (3).

3. 3. The hydroponic cultivation system according to claim 1 or 2, wherein the second openings (9) are uniformly distributed over the entire surface of the support member (8), and preferably the support member (8) is a mesh tray.

4. The hydroponic cultivation system according to any one of claims 1 to 3, wherein the cover device (10) is movable, allowing access to the support member (8) in a first position of the movable cover device (10), and blocking access to the support member (8) in a second position of the movable cover device (10).

5. 5. The hydroponic cultivation system according to any one of claims 1 to 4, wherein the upper section (5) comprises a second wall element (11) substantially parallel to and at a predetermined distance from the first wall element (3) for receiving the support member (8).

6. 6. The hydroponic system according to any one of claims 1 to 5, wherein the system comprises an adjusting device for adapting a predetermined distance between the support member (8) and the first wall element (3) and / or between the second wall element (11) and the first wall element (3).

7. The hydroponic cultivation system further comprises: - said gas pressure device arranged for generating pressurized gas, said gas pressure device being communicatively coupled to said connection arrangement (7) for supplying pressurized gas to said lower section (4) via said connection arrangement (7); The hydroponic cultivation system according to any one of claims 1 to 6, comprising:

8. Use of the hydroponic system according to any one of claims 1 to 7 for the germination of seeds and the growth of seeds into plants.

9. 1. A method for the germination of a seed and its development into a plant, comprising: - supplying liquid to the upper section (5) of the receiving space (2) of the hydroponic system according to claims 1 to 7; - supplying pressurized gas to said lower section (4) via said connection arrangement (7) and said gas pressure device; - providing seeds, seedlings and / or plants on said support member (8); - maintaining said support member (8) at a predetermined distance above said liquid, said support member (8) comprising a second opening (9) for gas-liquid communication and for allowing roots to grow through said second opening (9); A method comprising:

10. The method further comprises: - delimiting said receiving space (2) at its upper side by means of a cover device (10) enclosing said support member (8) together with said container (1); 10. The method of claim 9, comprising:

11. The method further comprises: - adjusting the predetermined distance between the support member 8 and the liquid by means of said adjusting arrangement; 11. The method of claim 9 or 10, comprising:

12. A method according to any one of claims 9 to 11, wherein the liquid is or comprises water.

13. A method according to any one of claims 9 to 12, wherein the distance between the surface of the liquid and the support member (8) is between 0.1 and 7 cm, preferably between 0.2 and 5 cm, more preferably between 0.5 and 2 cm.

14. A method according to any one of claims 9 to 13, wherein the pressurised gas flow through the first opening (6) provides a supply of single and / or coalesced gas bubbles which burst at the surface of the liquid.

15. A method according to any one of claims 9 to 14, wherein a pressure build-up is achieved for pressurized gas flow through 90-100% of the first openings (6).

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