WO2022245792A1

WO2022245792A1 - Growing-media amendment for crop production in containers utilizing sub-irrigation

Info

Publication number: WO2022245792A1
Application number: PCT/US2022/029585
Authority: WO
Inventors: Matthew J. LAROSA; Nico Hawley-Weld; Ilse RENNER; Michelle M. MCDONALD; Jin Xin
Original assignee: Upward Enterprises Inc.
Priority date: 2021-05-17
Filing date: 2022-05-17
Publication date: 2022-11-24

Abstract

A hydrophobic soil amendment can be applied to growing media for sub-irrigation crop-growth systems to reduce an amount of growing media needed for these systems and to reduce a portion of the growing medium in a container where the growing medium may be oxygen deficient.

Description

Growing-Media Amendment for Crop Production in Containers Utilizing

Sub-irrigation

FIELD OF THE INVENTION

[0001] The described implementations relate to the fields of horticulture and agriculture. More specifically, the implementations relate to hydrophobic soil amendments or additives that may be applied to growing media for crop-production containers that are sub-irrigated.

BACKGROUND

[0002] In the production of plants and other crops, growing media provides, among other things, physical support for the crop and water transport to the crop. The transport of water through growing media via capillary action is a fundamental process in horticulture. In the industry, growing media such as cellulose (as described in international Patent Publication No.

WO 1997016960A1, which is incorporated herein by reference in its entirety) and cloth (as described in U.S. Published Patent Application No. 2014/0137471, which is incorporated herein by reference in its entirety) can provide improved capillary strengths appropriate for specific growing conditions. Similarly, sphagnum peat is often manufactured with a wetting agent to encourage the uptake of water after the peat has been dried (See, Sheldrake Jr, R. and Matkin, O.A., “Wetting agents for peat moss,” ActaHortic. 18, 37-42 (1971)).

[0003] In open-field agriculture and for some greenhouse agricultural applications, a new class of soil amendments has emerged that render an upper surface-layer of soil hydrophobic, examples of which are described in U.S. Published Patent Application Nos. 2005/0150417 and 2016/0208166 and in international Patent Publication No. WO2016126887, each of which applications is incorporated by reference herein in its entirety. The intended use of hydrophobic amendments is to apply a liquid coating to the upper soil layer, which upon drying, forms a hydrophobic surface layer of soil that helps retain water in the soil below the upper layer and near the plants’ roots, reduces evaporation, and thus reduces the total amount of irrigation required. Substantial work has been done to develop cost-effective and easy-to-apply hydrophobic additives for this purpose. SUMMARY

[0004] The inventors have recognized and appreciated that conventional approaches to sub irrigation crop-growth systems include a region of growing medium in crop containers or rafts that can be unhealthy for developing and mature crops. In particular, the inventors have recognized and appreciated that there can be an oxygen-deficient region in the growing medium between the sub-irrigation system ( e.g ., the water level of a liquid on which a raft containing crops and growing medium floats) and a top region of the growing medium. The oxygen- deficient region may lie in a high-moisture region of the growing medium where there is an insufficient gaseous oxygen reservoir in the growing medium and where the crop has depleted oxygen from the liquid reservoir in the oxygen-deficient region and the liquid cannot be exchanged at a sufficient rate in the region to replace the depleted oxygen. This oxygen- deficient region is due in part to the capillary strength of the growing medium that wicks moisture up into the medium from the sub-irrigation system. The thickness of the oxygen- deficient region can be proportional to the total thickness of the growing medium in the raft or container that is sub-irrigated. The oxygen-deficient region can extend an appreciable distance in conventional thicknesses of growing media and can impede crop growth.

[0005] In view of the foregoing, the present disclosure relates to hydrophobic soil amendments (also referred to as “hydrophobic additives”) that are used in a novel way for sub-irrigation systems, such as deep-water and shallow-water agricultural production systems, to impede the transport of water into the growing media that supports one or more crops. The crops may be germinated and grown in one or more containers that are at least partly filled with a growing medium and irrigated from below the container with a sub-irrigation system. In some cases, a selected amount of hydrophobic soil amendment may be applied to or dispersed in the entire growing medium to make the entire growing medium partially hydrophobic. In other cases, a hydrophobic soil amendment can be applied to at least part of the growing medium (e.g., a lower layer). Such hydrophobic treatment can reduce the thickness of the oxygen-deficient region in the container and mitigate its effect on crop growth.

[0006] Some implementations relate to a rowing medium to be placed in a container for growth of at least one crop in the growing medium with a sub-irrigation system. The growing medium can include a growing medium component and a hydrophobic soil amendment applied to the growing medium component to form a treated component that reduces the capillary action of the growing medium and impedes the transport of the liquid into the growing medium, when irrigated by the liquid from below the growing medium with the sub-irrigation system, compared to the growing medium having the same amount of growing medium component without the hydrophobic soil amendment applied to the growing medium component.

[0007] Some implementations relate to a sub-irrigation crop-growth system comprising: a raft having a container to support growing medium and at least one crop; and growing medium in the container treated with a hydrophobic soil amendment to reduce the capillary action of the growing medium and impede the transport of water from the sub-irrigation into the growing medium.

[0008] Some implementations relate to a growing medium to be placed in a container for growth of at least one crop in the growing medium with a sub-irrigation system. The growing medium can include a growing medium component and hydrophobic particles mixed with the growing medium component to reduce the capillary action of the growing medium and impede the transport of the liquid into the growing medium, when irrigated by the liquid from below the growing medium with the sub-irrigation system, compared to the growing medium without the hydrophobic particles mixed therein.

[0009] Some implementations relate to a method of making growing medium for growing one or more crops in a container using a sub-irrigation system. The method can include acts of: applying a hydrophobic soil amendment to a growing medium component to form a treated component that, when placed in the container and irrigated by a liquid from below the growing medium, reduces the capillary action of the growing medium and impedes the transport of the liquid into the growing medium compared to the growing medium having the same amount of growing medium component without the hydrophobic soil amendment applied to the growing medium component; and forming the growing medium from at least the treated component.

[0010] Some implementations relate to a system for growing at least one crop with a sub irrigation system. The system can include: a container having at least one cell in which a plant can grow; at least one opening in a base of the at least one cell to allow ingress of liquid from the sub-irrigation system; and growing medium within the at least one cell. The growing medium can include a growing medium component and a hydrophobic soil amendment applied to the growing medium component to form a treated component that reduces the capillary action of the growing medium and impedes the transport of the liquid into the growing medium, when irrigated by the liquid from below the growing medium, compared to the growing medium having the same amount of growing medium component without the hydrophobic soil amendment applied to the growing medium component.

[0011] All combinations of the foregoing concepts and additional concepts discussed in greater detail below (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter disclosed herein. In particular, all combinations of claimed subject matter appearing at the end of this disclosure are contemplated as being part of the inventive subject matter disclosed herein. The terminology explicitly employed herein that also may appear in any disclosure incorporated by reference should be accorded a meaning most consistent with the particular concepts disclosed herein.

BRIEF DESCRIPTIONS OF THE DRAWINGS

[0012] The skilled artisan will understand that the drawings primarily are for illustrative purposes and are not intended to limit the scope of the inventive subject matter described herein. The drawings are not necessarily to scale; in some instances, various aspects of the inventive subject matter disclosed herein may be shown exaggerated or enlarged in the drawings to facilitate an understanding of different features. In the drawings, like reference characters generally refer to like features (e.g., functionally similar and/or structurally similar components).

[0013] FIG. 1A depicts a container and sub-irrigation system for germinating and growing a crop.

[0014] FIG. IB depicts an example of a container that can be used with the growing medium as depicted in FIG. 1A.

[0015] FIG. 1C depicts a portion of the growing medium and container of FIG. 1A.

[0016] FIG. 2 depicts a first method for preparing partially-hydrophobic growing media.

[0017] FIG. 3 depicts a second method for preparing partially-hydrophobic growing media. [0018] FIG. 4 depicts apparatus for measuring the water uptake of growing media. DETAILED DESCRIPTION

[0019] Crop production systems of particular interest in recent years include deep water culture or shallow water culture growing systems. These growing systems are examples of sub irrigation systems where the primary source of water (typically with added nutrients) is provided from below the crops. In deep water or shallow water sub-irrigation systems, crops are contained within rafts that float on ponds of primarily water. Deep and shallow water production systems offer high thermal stability and are easy to automate by using water as a “frictionless conveyor” to transport the rafts (See, Jensen, M.. “Deep Flow Hydroponics-Past, Present and Future,” Environmental Science (2010). As used herein “crops” can refer to edible vegetable crops, berry crops, flowers, and mushrooms, though the invention is not limited to only these types of crops.

[0020] FIG. 1A depicts a simplified example of a sub-irrigation crop-growth system 100. Only one container 102 is shown for a single seedling or crop 130 to simplify the drawing. In an implemented growing system, there can be tens to hundreds of such containers 102 each containing one or more seedlings 130. In some cases, there can be hundreds to thousands of seedlings per container 102. The container 102 can include one or more cells 115 or compartments separated by walls as shown in FIG. IB. Each cell 115 can contain one or more plants and include a hole at the base of the cell to allow ingress of liquid 110 to the growing medium and outward growth of roots into the liquid. The container 102 can be configured to float with the growing medium on the liquid 110.

[0021] The containers 102 can be adapted for sub-irrigation and may be formed as a raft that floats on the liquid 110 below the raft. The liquid 110 used can comprise water with added nutrients ( e.g ., fertigation water) or may be plain irrigation water. In some cases, the liquid 110 can be present throughout the entire growth cycle of the crops. In some implementations, the liquid 110 can be applied and removed periodically during the growth cycle of the crops. In yet other implementations, the liquid 110 may be sprayed onto the roots and/or underside of the containers 102 continuously or periodically.

[0022] Each container can be filled or partially filled with a growing medium 120 in which a seed germinates and grows to a harvestable crop. Each container 102 can have one or more openings to admit the liquid 110. A lower portion of the growing medium in each container may contact the liquid 110. In some cases, at least some of the crops’ root systems grow into the liquid, as depicted in FIG. 1A. When the crop matures, an edible portion of the crop can be harvested. For some implementations, remaining crop matter and growing medium 120 can be removed from the containers 102 so that the containers can be cleaned and reused. In some cases, the growing medium 120 may be cleaned and reused.

[0023] The term “growing medium” refers to physically self-contiguous matter that supports plant growth and which can include one or more growing medium components. For example, a growing medium can have two growing medium components such as peat and wood fibers. In some cases, a growing medium can comprise a synthetic or natural mesh that is impregnated with another component ( e.g ., peat moss). Growing medium components can include, but are not limited to, granules, fibers, chips, textiles, foams, membranes, and gels, coir, peat, perlite, vermiculite, mineral wool, cellulose, wood products, polymers, seed hulls, bagasse, and porous concrete. The growing medium can be loose or formed into solid plugs or sheets. In some cases, the growing medium can be formed as a composite of two or more different types of growing media that are mixed together (e.g., to form a composite loose mixture) and then laminated, bound with a binding agent, and/or pressed together into a solid plug or sheet.

[0024] For early and later stages of germination and crop growth, constant exposure of the growing medium 120 to the liquid 110 in sub -irrigation production systems can create horticultural challenges. Such challenges can include excess moisture at or near the root-stem junction and deoxygenation of a layer of the growing media 120. Oxygen supply to the growing crops’ roots can come from two reservoirs within the growing medium 120. One reservoir is a gaseous reservoir of air within the porous growing medium. A second reservoir is a liquid reservoir from oxygen-containing liquid (e.g, water) within the porous growing medium. The gaseous reservoir may be replenished by diffusion of air in and out of the porous medium as the crop consumes oxygen from this reservoir. Replenishment of the liquid reservoir as it is depleted of oxygen by the growing crop can be more problematic. Although oxygenation of the liquid 110 below the container 102 can be controlled with relative ease, exchange of oxygen-depleted liquid within the growing medium may not be at sufficient rates for thick growing media. As a result, there can be an oxygen-deficient region 140 that develops in the growing medium 120 within the zone of high moisture 150, as depicted in FIG. 1C. Oxygenation of the liquid reservoir within this region can be uncontrollable in practice and the region may have a deficient supply of oxygen for the growing crop.

[0025] One way to mitigate these challenges, as depicted in FIG. 1A, is to implement a sufficient capillary distance D_c from the sub-irrigation water level 112 to the bottom of the safe seeding zone (a layer of the growing medium in the container where seeding and germination occur). In the safe seeding zone 105, the gaseous reservoir can provide an adequate supply of oxygen to the young crop. When sub-irrigation is combined with untreated growing medium that has high capillary strength, a relatively high capillary distance D_c (e.g, from 1 inch to 4 inches) may be required from the water level 112 to the safe seeding zone 105 depending upon the type of crop. However, increasing the distance D_c to the safe seeding zone 105 can increase costs of operation. For example, increasing the value D_c requires a taller raft, more growing media 120 within the raft’s containers, and a more massive raft when filled with growing media. A taller raft represents an increased cost in terms of space to accommodate the rafts as well as construction materials for the raft. In large-scale operations, the rafts may be stacked outside the fertigation ponds for a period of time and taller rafts would require more space. Additionally, the fertigation ponds may be stacked vertically, and a taller raft requires a larger vertical spacing between the fertigation ponds. An increase in growing media for each raft represents a direct increase in financial cost. An increase in mass carried by the raft can require increased buoyancy (an increase in size of buoyant features on the raft) to float the raft, growth media, and crops. An increase in buoyant feature sizes may decrease an amount of raft area available for crop growth, increase raft complexity and manufacturing cost, and also contribute to an increase in raft size. Additionally, the growing crop may still grow downward through a region that is oxygen deficient until its roots reach the liquid 110 where oxygenation can be readily controlled.

[0026] The inventors have recognized and appreciated that hydrophobic soil amendments may be used for sub-irrigation crop-growth systems in an opposite approach to conventional uses described above for open-field and greenhouse agricultural production. Instead of using a hydrophobic soil amendment to trap water around the plants’ roots, as is done in the open-field and greenhouse applications, the hydrophobic soil amendment can be applied to impede the flow of water into the growing medium and to the safe-seeding zone 105 where the young crop germinates and begins to grow. [0027] For sub-irrigation crop-growth systems, one or more hydrophobic soil amendments may be applied to the entire growing medium in the container 102 or to part of the growing medium 120 in each container ( e.g ., a lower layer such as the zone of high moisture 150) to impede the capillary action and flow of liquid 110 into the growing medium and to the safe-seeding zone 105. The reduction in capillary action can be compensated for by reducing the capillary distance Dc. As a result, the thickness or depth of the growing medium 120 can be reduced compared to an untreated growing medium. As a result, the thicknesses of the zone of high moisture 150 and the oxygen-deficient region 140 can be decreased. As just one example, the thickness of the growing medium 120 can be decreased from 2.5 inches to 1.75 inches for one type of crop. This reduction in total thickness of the growing medium means that less growing medium 120 is required in each container 102. In some cases, the reduction in depth leads to a reduction in growing media from 10% up to 50%, which can be a substantial cost reduction in large-scale crop-production enterprises. Additionally, the raft sizes can have a smaller height and be less massive when filled with growing media, reducing costs associated with space occupied by rafts, buoyant features, and raft complexity.

[0028] A reduction in the capillary distance can reduce the thickness of an oxygen-deficient region 140 within the zone of high moisture 150. Essentially, the layer thicknesses of the zone of high moisture 150 and oxygen-deficient region 140 are reduced as a result of the reduction of total thickness in growing medium 120. The reduction in thickness of the oxygen-deficient region 140 provides less of an impediment to rapid crop development. For example, the developing roots of the plant have a shorter distance to penetrate before entering the region below where oxygen and nutrients are readily supplied by the liquid 110.

[0029] Sub-irrigation crop-growth systems that can benefit from such hydrophobic soil amendments include crop-growth systems where the growing media 120 is irrigated from below, such as deep-water culture, shallow-water culture, and/or flood-and-drain systems. Sub irrigation can be continuous or intermittent and can be implemented in the form of bulk liquid irrigation or alternatively as droplets such in a spray, fog, or mist.

[0030] The column of growing medium 120 in each container 102 can be treated, in whole or in part, with a hydrophobic soil amendment. The amount of hydrophobic soil amendment applied should not make the resulting treated growing medium 120 completely hydrophobic such that it blocks capillary action and uptake of liquid 110. Instead, the treated growing medium 120 should be partial hydrophobic such that its capillary action and uptake of liquid 110 is impeded when compared to untreated growing medium 120. Examples of hydrophobic soil amendments include, but are not limited to sodium methylsiliconate, potassium methylsiliconate, sodium orthosilicate, potassium orthosilicate, sodium metasilicate, potassium metasilicate, an alkali metal alkyl siliconate compound, an alkali metal silicate compound, polysorbate, hydrophobic- coated particles (with coatings such as poly-caprolactone (PCL), poly-beta-hydroxyalkanoates (PHA), poly-glycolic acid (PGA), poly -lactic acid (PLA), and poly-lactic-co-glycolic acid (PLGA)), hydrophobic particles formed from a synthetic polymer-based material such as plastic, silicone, or rubber ( e.g ., polystyrene, polytetrafluoroethylene (PTFE), polymethyl methacrylate PMMA, nylon, polyethylene terephthalate (PET), polydimethylsiloxane, etc.), paraffin wax, plant waxes, plant oils, organic acids, and latexes or some combination of these hydrophobic soil amendments.

[0031] It will be appreciated from the foregoing description that there are at least two ways to deploy treated, partially -hydrophobic growing medium into containers 102 that are used in sub irrigation growing systems. One way is to only place partially-hydrophobic growing medium in a sub-surface layer of the containers. For example, the partially-hydrophobic growing medium can be covered by at least one layer of untreated growing medium in the container. Another approach is to only dispose partially-hydrophobic growing medium in the containers 102 ( i.e ., there is no layer of untreated growing medium in the container), such that the partially- hydrophobic growing medium extends from the surface to the bottom of the container and plant roots extend throughout the partially-hydrophobic growing medium.

[0032] In some cases, treatment of the entire growing medium 120 to be placed in growing containers 102 can be beneficial as opposed to treating growing medium for a sub-surface layer within each container. For example, application of the hydrophobic soil amendment to the entire growing medium provides a uniform modification of the medium’s capillary strength throughout the container, which may provide a more even distribution of crop roots within the container. Uniform treatment of the growing medium 120 can make it easier to tune the capillary strength of the growing medium and know its value throughout the container. Capillary strength for growing medium may be determined from water uptake measurements, examples of which are described below in connection with FIG. 4. Further, a uniformly-treated growing medium 120 may be easier to load into the containers compared to a non-uniform, layered structure of differently treated growing media. Additionally, a uniformly-treated growing medium 120 may also reduce evaporation at the surface (compared to a container having an untreated surface layer), which can reduce moisture buildup (and risk of fungus) in a dense canopy above the growing medium. However, some implementations may employ one or more layers of growing media in each container that have been treated differently with hydrophobic soil amendment(s) and there may also be a layer of untreated growing medium 120 in each container.

[0033] Hydrophobic soil amendments can be applied to growing media in several ways. One example method for treating growing media is depicted in FIG. 2. In this approach, a first untreated growing medium is treated with a hydrophobic soil amendment to make (act 210) the growing medium fully hydrophobic (i.e., it will not uptake water when placed in contact with water). The treatment of the growing medium may be quantified, for example, as a weight ratio (e.g. pounds of hydrophobic soil amendment to pounds of untreated growing medium), though other ways to quantify the treatment are possible (e.g, volume of liquid amendment to weight or volume of growing medium).

[0034] The method can further include selecting (act 220) and/or adjusting the mixing ratio A:B between the fully hydrophobic growing medium and untreated growing medium to tune the partial hydrophobicity of the resulting composition to have the desired water uptake characteristic. The treated, fully-hydrophobic growing medium can then be mixed (act 230) according to the selected ratio A:B (e.g, by volume or weight) with the untreated growing medium to produce a partially-hydrophobic growing medium having the desired water uptake characteristic. The mixing ratio (by volume or weight) may be from 25:75 to 90: 10 for some applications. In some cases, the mixing ratio (by volume or weight) may be from 5:95 to 95:5.

In yet other cases, the mixing ratio (by volume or weight) may be from 15:85 to 70:30. The resulting partially-hydrophobic growing medium can be added (act 240) to one or more containers in which plants will be grown using a sub-irrigation system.

[0035] Other methods of treatment are possible. For example, one growing medium, multiple growing media, or one or more growing medium components can be combined with one growing medium, multiple growing media, or one or more growing medium components that has or have been treated with a hydrophobic soil amendment. In some implementations, a fully hydrophobic component ( e.g silicone or silicone-coated particles) can be mixed with untreated and/or treated growing medium to adjust the water uptake characteristic of the resulting composition. In some cases, a first growing medium may be treated with a reduced amount of hydrophobic soil amendment, such that the treated growing medium is partially hydrophobic, before it is mixed with one or more other untreated or treated growing medium components to produce a growing medium having a desired water uptake characteristic.

[0036] FIG. 3 depicts another process for treating a growing medium with a hydrophobic soil amendment to produce a partially-hydrophobic growing medium. In this approach, a liquid hydrophobic soil amendment is diluted (act 310) with a diluent by a selected amount to produce a diluted soil amendment. A mixing ratio of the diluted liquid soil amendment to untreated growing medium can be selected (act 320) to obtain a growing medium have a desired water uptake characteristic. The mixing ratio can be any of the above-described ratios by volume or weight. The diluted liquid hydrophobic amendment can then be applied (act 330) to an untreated growing medium. The resulting mix of diluted soil amendment to untreated growing medium is a partially-hydrophobic growing medium. In this method, the dilution level allows for the partial hydrophobicity of the final growing medium to be carefully tuned. In an alternative approach, the diluted hydrophobic amendment may be applied to a growing medium component that is later added to at least one other component of a growing medium to produce a partially- hydrophobic growing medium. The resulting partially-hydrophobic growing medium can be added (act 340) to one or more growing containers in which plants will be grown using a sub irrigation system.

[0037] Acts of the methods depicted in FIG. 2 and FIG. 3 may be combined for some implementations. For example, the partially-hydrophobic growing media produced by each process may be mixed together to form a partially-hydrophobic growing medium. Alternatively, the partially-hydrophobic growing medium produced by the process depicted in FIG. 3 may be used in place of the fully-hydrophobic growing medium in the process of FIG. 2. A drying step and/or compression step (not shown) can also be included after any step in which the hydrophobic soil amendment is applied. Drying and/or compression can be used for packaging and shipping purposes. [0038] Another method for producing a partially-hydrophobic growing medium is to use a method depicted in FIG. 2 or FIG. 3, or some combination thereof, where the first untreated growing medium is a dried or dehydrated growing medium such as peat or coir, for example.

The untreated growing medium may have been dried (and possibly compressed) for shipment.

In such a method, the hydrophobic coating or diluted hydrophobic coating can be added to the untreated growing medium as part of a rehydration process of that growing medium. A drying step may or may not be used after rehydration.

[0039] Alternatively, in some cases a method of FIG. 2, FIG. 3, or some combination thereof may be employed to produce a partially-hydrophobic or fully-hydrophobic growing medium such as peat or coir before the growing medium is dried (and possibly compressed) prior to shipment. In this case, the growing medium would be ready for use by the consumer without the need to apply a hydrophobic coating by the consumer. The shipped growing medium may be partially hydrophobic or may be fully hydrophobic. A shipped fully-hydrophobic growing medium may be used in the method of FIG. 2 to produce a partially-hydrophobic growing medium. The shipped growing medium may be provided with instructions for mixing the partially hydrophobic or fully-hydrophobic growing medium with untreated growing medium to obtain a desired water uptake characteristic when used in a sub-irrigation system. The instructions may include one or more tables that lists mixing ratios to be used for different types of untreated growing media and different thicknesses of growing media to be used in a container 102. Packages in which partially-hydrophobic or fully-hydrophobic growing medium is marketed can indicate that the growing medium is intended for sub-irrigation applications.

[0040] To quantify the hydrophobicity or capillary strength of the treated growing medium, the water uptake characteristic method (WOK) can be used (See, Geuijen, W.H.C. and Verhagen, J.B.G.M., “Analysis of water uptake of growing media on the relation to water uptake in horticultural practice,” Acta Hortic. (2017) 1168, pp. 113-118). In this method, the growing medium is dried completely and placed in a 10 cm column above a thin film of water. The mass and therefore volume of water uptake over time is measured.

[0041] FIG. 4 depicts apparatus 400 that can be used in one of several approaches to measuring the water uptake characteristic for growing media that may be used in sub-irrigation crop- production systems. In a first basin 401, a body of water 410 (as opposed to a thin film of water) can be located beneath the column of growing medium 120. The growing medium 120 can be supported in a container 402 that has openings to admit water into the container. The body of water 410 and arrangement of the growing medium 120 as depicted in FIG. 4 may better emulate growing environments in which the growing medium will be used. The body of water 410 can be maintained at a constant level with supply-and-return tubes 440 running to a second basin 404, for example. The growing medium 120 and container 402 can be supported by a scaffold 420, which may be adjustable in height, such that the growing medium 120 can be located with respect to the water level in the container 402 ( e.g ., at a same height as it would be located in a raft on a fertigation pond in a sub-irrigation crop-growth system). A scale 450 can support the basin 401 and be used to measure the amount of water uptake in the growing medium 120

[0042] Using the apparatus of FIG. 4 to determine water uptake, partially-hydrophobic growing media of the above-described implementations can reach, at equilibrium, a 5-75% volumetric water content (VWC) on average throughout a 10-cm-high column of growing medium. The partially-hydrophobic growing media of the above-described implementations can also reduce the capillary strength (measured by equilibrium VWC) by 5-95% of the original capillary strength of the untreated growing medium.

[0043] Growing medium, containers, sub-irrigation systems, and related methods may be implemented in different configurations, some of which are listed below.

(1) Growing medium to be placed in a container for growth of at least one crop in the growing medium with a sub-irrigation system, the growing medium comprising: a growing medium component; and a hydrophobic soil amendment applied to the growing medium component to form a treated component that reduces the capillary action of the growing medium and impedes the transport of the liquid into the growing medium, when irrigated by the liquid from below the growing medium with the sub-irrigation system, compared to the growing medium having the same amount of growing medium component without the hydrophobic soil amendment applied to the growing medium component.

(2) The growing medium of configuration (1), wherein the treated component is the only component of the growing medium. (3) The growing medium of configuration (1) or (2), wherein the treated component is fully hydrophobic.

(4) The growing medium of any one of configurations (1) through (3), further comprising at least a second growing medium component that is mixed with the treated component.

(5) The growing medium of any one of configurations (1) through (4), wherein the growing medium component comprises coir or peat.

(6) The growing medium of any one of configurations (1) through (5), wherein the growing medium component comprises perlite or vermiculite.

(7) The growing medium of any one of configurations (1) through (6), wherein the growing medium component comprises cellulose or seed hulls.

(8) The growing medium of any one of configurations (1) through (7), wherein the growing medium component comprises wood products or bagasse.

(9) The growing medium of any one of configurations (1) through (8), wherein the hydrophobic soil amendment comprises sodium methylsiliconate or potassium methylsiliconate.

(10) The growing medium of any one of configurations (1) through (9), wherein the hydrophobic soil amendment comprises sodium metasilicate or potassium metasilicate.

(11) The growing medium of any one of configurations (1) through (10), wherein the hydrophobic soil amendment comprises sodium orthosilicate or potassium orthosilicate.

(12) The growing medium of any one of configurations (1) through (11), wherein the hydrophobic soil amendment comprises an alkali metal alkyl siliconate compound.

(13) The growing medium of any one of configurations (1) through (12), wherein the hydrophobic soil amendment comprises an alkali metal silicate compound.

(14) The growing medium of any one of configurations (1) through (13), wherein the hydrophobic soil amendment comprises hydrophobic-coated particles.

(15) The growing medium of configuration (14), wherein a coating of the hydrophobic- coated particles comprises poly-caprolactone. (16) The growing medium of configuration (14), wherein a coating of the hydrophobic- coated particles comprises poly-glycolic acid.

(17) The growing medium of configuration (14), wherein a coating of the hydrophobic- coated particles comprises poly-lactic acid.

(18) The growing medium of configuration (14), wherein a coating of the hydrophobic- coated particles comprises poly-lactic-co-glycolic acid.

(19) The growing medium of configuration (14), wherein a coating of the hydrophobic- coated particles comprises at least one of paraffin wax.

(20) The growing medium of configuration (14), wherein a coating of the hydrophobic- coated particles comprises at least one of a plant wax or a plant oil.

(21) The growing medium of any one of configurations (1) through (20), wherein the hydrophobic soil amendment comprises polysorbate.

(22) The growing medium of any one of configurations (1) through (21), wherein the hydrophobic soil amendment comprises poly-beta-hydroxyalkanoates.

(23) The growing medium of any one of configurations (1) through (22), wherein the hydrophobic soil amendment comprises an organic acid.

(24) The growing medium of any one of configurations (1) through (23), wherein the hydrophobic soil amendment comprises a latex.

(25) The growing medium of any one of configurations (1) through (24), wherein the hydrophobic soil amendment comprises at least one of a paraffin wax, a plant wax, or a plant oil.

(26) Growing medium to be placed in a container for growth of at least one crop in the growing medium with a sub-irrigation system, the growing medium comprising: a growing medium component; and hydrophobic particles mixed with the growing medium component to reduce the capillary action of the growing medium and impede the transport of the liquid into the growing medium, when irrigated by the liquid from below the growing medium with the sub irrigation system, compared to the growing medium without the hydrophobic particles mixed therein. (27) The growing medium of configuration (26), wherein the growing medium component comprises coir or peat.

(28) The growing medium of configuration (26) or (27), wherein the growing medium component comprises perlite or vermiculite.

(29) The growing medium of any one of configurations (26) through (28), wherein the growing medium component comprises cellulose or seed hulls.

(30) The growing medium of any one of configurations (26) through (29), wherein the growing medium component comprises wood products or bagasse.

(31) The growing medium of any one of configurations (26) through (30), wherein the hydrophobic particles are formed from a synthetic polymer-based material.

(32) The growing medium of configuration (31), wherein the polymer-based material comprises polystyrene.

(33) The growing medium of configuration (31) or (32), wherein the polymer-based material comprises polytetrafluoroethylene.

(34) The growing medium of any one of configurations (31) through (33), wherein the polymer-based material comprises polymethyl methacrylate.

(35) The growing medium of any one of configurations (31) through (34), wherein the polymer-based material comprises nylon.

(36) The growing medium of any one of configurations (31) through (35), wherein the polymer-based material comprises polyethylene terephthalate.

(37) The growing medium of any one of configurations (31) through (36), wherein the polymer-based material comprises rubber.

(38) The growing medium of any one of configurations (31) through (37), wherein the polymer-based material comprises polydimethylsiloxane.

(39) The growing medium of any one of configurations (31) through (38), wherein the polymer-based material comprises latex. (40) The growing medium of any one of configurations (31) through (39), wherein the polymer-based material comprises paraffin wax.

(41) A method of making growing medium for growing one or more crops in a container using a sub-irrigation system, the method comprising: applying a hydrophobic soil amendment to a growing medium component to form a treated component that, when placed in the container and irrigated by a liquid from below the growing medium, reduces the capillary action of the growing medium and impedes the transport of the liquid into the growing medium compared to the growing medium having the same amount of growing medium component without the hydrophobic soil amendment applied to the growing medium component; and forming the growing medium from at least the treated component.

(42) The method of (41), further comprising: adding the treated component into the container in a sub-surface layer of the growing medium; and covering the treated component with a layer of growing medium that does not contain the hydrophobic soil amendment.

(43) The method of (41) or (42), further comprising adding the treated component into the container such that the treated component is distributed throughout the entire thickness of the growing medium in the container.

(44) The method of any one of (41) through (43), wherein applying the hydrophobic soil amendment makes the treated component fully hydrophobic, the method further comprising: mixing the treated component with a second growing medium component to form a partially - hydrophobic growing medium.

(45) The method of (44), wherein a ratio by weight of the treated component to the second growing medium component has a value in a range from 5:95 to 95:5.

(46) The method of (44) or (45), further comprising dehydrating the partially- hydrophobic growing medium.

(47) The method of any one of (41) through (43), wherein applying the hydrophobic soil amendment comprises: diluting a liquid hydrophobic soil amendment to form a diluted liquid soil amendment; and applying the diluted liquid soil amendment to the growing medium component. (48) The method of (47), wherein a ratio by weight of the diluted liquid soil amendment to the growing medium component has a value in a range from 5:95 to 95:5.

(49) The method of (47) or (48), wherein applying the diluted liquid soil amendment to the growing medium component hydrates the growing medium component from a dehydrated and compressed state.

(50) The method of any one of (47) through (48), further comprising: dehydrating the growing medium after applying the hydrophobic soil amendment to the growing medium component.

(51) A system for growing at least one crop with a sub-irrigation system, the system comprising: a container having at least one cell in which a plant can grow; at least one opening in a base of the at least one cell to allow ingress of liquid from the sub -irrigation system; and growing medium within the at least one cell. The growing medium comprises: a growing medium component; and a hydrophobic soil amendment applied to the growing medium component to form a treated component that reduces the capillary action of the growing medium and impedes the transport of the liquid into the growing medium, when irrigated by the liquid from below the growing medium, compared to the growing medium having the same amount of growing medium component without the hydrophobic soil amendment applied to the growing medium component.

(52) The system of configuration (51), wherein the treated component is located in a sub surface layer of the growing medium.

(53) The system of configuration (51), wherein the treated component is distributed throughout an entire thickness of the growing medium within the at least one cell.

(54) The system of any one of configurations (51) through (53), wherein the container is configured to float on the liquid while containing the growing medium.

CONCLUSION

[0044] While various inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the inventive teachings is/are used. Those skilled in the art will recognize or be able to ascertain, using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.

[0045] Also, various inventive concepts may be embodied as one or more methods, of which an example has been provided. The acts performed as part of the method may be ordered in any suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include performing some acts simultaneously, even though shown as sequential acts in illustrative embodiments.

[0046] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms.

[0047] The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.”

[0048] The phrase “and/or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the components so conjoined, i.e., components that are conjunctively present in some cases and disjunctively present in other cases. Multiple components listed with “and/or” should be construed in the same fashion, i.e., “one or more” of the components so conjoined. Other components may optionally be present other than the components specifically identified by the “and/or” clause, whether related or unrelated to those components specifically identified. Thus, as a non-limiting example, a reference to “A and/or B”, when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A only (optionally including components other than B); in another embodiment, to B only (optionally including components other than A); in yet another embodiment, to both A and B (optionally including other components); etc.

[0049] As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and/or” as defined above. For example, when separating items in a list, “or” or “and/or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of components, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of’ or “exactly one of,” or, when used in the claims, “consisting of,” will refer to the inclusion of exactly one component of a number or list of components. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e. “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” when used in the claims, shall have its ordinary meaning as used in the field of patent law.

[0050] As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more components, should be understood to mean at least one component selected from any one or more of the components in the list of components, but not necessarily including at least one of each and every component specifically listed within the list of components and not excluding any combinations of components in the list of components.

This definition also allows that components may optionally be present other than the components specifically identified within the list of components to which the phrase “at least one” refers, whether related or unrelated to those components specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and/or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including components other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including components other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other components); etc.

[0051] In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of’ and “consisting essentially of’ shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.

Claims

1. Growing medium to be placed in a container for growth of at least one crop in the growing medium with a sub-irrigation system, the growing medium comprising: a growing medium component; and a hydrophobic soil amendment applied to the growing medium component to form a treated component that reduces the capillary action of the growing medium and impedes the transport of the liquid into the growing medium, when irrigated by the liquid from below the growing medium with the sub-irrigation system, compared to the growing medium having the same amount of growing medium component without the hydrophobic soil amendment applied to the growing medium component.

2. The growing medium of claim 1, wherein the treated component is the only component of the growing medium.

3. The growing medium of claim 2, wherein the treated component is fully hydrophobic.

4. The growing medium of claim 1, further comprising at least a second growing medium component that is mixed with the treated component.

5. The growing medium of claim 1, wherein the growing medium component comprises coir or peat.

6. The growing medium of claim 1, wherein the growing medium component comprises perlite or vermiculite.

7. The growing medium of claim 1, wherein the growing medium component comprises cellulose or seed hulls.

8. The growing medium of claim 1, wherein the growing medium component comprises wood products or bagasse.

9. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises sodium methylsiliconate or potassium methylsiliconate.

10. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises sodium metasilicate or potassium metasilicate.

11. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises sodium orthosilicate or potassium orthosilicate.

12. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises an alkali metal alkyl siliconate compound.

13. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises an alkali metal silicate compound.

14. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises hydrophobic-coated particles.

15. The growing medium of claim 14, wherein a coating of the hydrophobic-coated particles comprises poly-caprolactone.

16. The growing medium of claim 14, wherein a coating of the hydrophobic-coated particles comprises poly-glycolic acid.

17. The growing medium of claim 14, wherein a coating of the hydrophobic-coated particles comprises poly-lactic acid.

18. The growing medium of claim 14, wherein a coating of the hydrophobic-coated particles comprises poly-lactic-co-glycolic acid.

19. The growing medium of claim 14, wherein a coating of the hydrophobic-coated particles comprises at least one of paraffin wax.

20. The growing medium of claim 14, wherein a coating of the hydrophobic-coated particles comprises at least one of a plant wax or a plant oil.

21. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises polysorbate.

22. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises poly-beta-hydroxyalkanoates.

23. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises an organic acid.

24. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises a latex.

25. The growing medium of any one of claims 1 through 8, wherein the hydrophobic soil amendment comprises at least one of a paraffin wax, a plant wax, or a plant oil.

26. Growing medium to be placed in a container for growth of at least one crop in the growing medium with a sub-irrigation system, the growing medium comprising: a growing medium component; and hydrophobic particles mixed with the growing medium component to reduce the capillary action of the growing medium and impede the transport of the liquid into the growing medium, when irrigated by the liquid from below the growing medium with the sub-irrigation system, compared to the growing medium without the hydrophobic particles mixed therein.

27. The growing medium of claim 26, wherein the growing medium component comprises coir or peat.

28. The growing medium of claim 26, wherein the growing medium component comprises perlite or vermiculite.

29. The growing medium of claim 26, wherein the growing medium component comprises cellulose or seed hulls.

30. The growing medium of claim 26, wherein the growing medium component comprises wood products or bagasse.

31. The growing medium of any one of claims 26 through 30, wherein the hydrophobic particles are formed from a synthetic polymer-based material.

32. The growing medium of claim 31, wherein the polymer-based material comprises polystyrene.

33. The growing medium of claim 31, wherein the polymer-based material comprises poly tetrafluoroethy 1 ene .

34. The growing medium of claim 31, wherein the polymer-based material comprises polymethyl methacrylate.

35. The growing medium of claim 31, wherein the polymer-based material comprises nylon.

36. The growing medium of claim 31, wherein the polymer-based material comprises polyethylene terephthalate.

37. The growing medium of claim 31, wherein the polymer-based material comprises rubber.

38. The growing medium of claim 31, wherein the polymer-based material comprises polydimethylsiloxane.

39. The growing medium of claim 31, wherein the polymer-based material comprises latex.

40. The growing medium of claim 31, wherein the polymer-based material comprises paraffin wax.

41. A method of making growing medium for growing one or more crops in a container using a sub-irrigation system, the method comprising: applying a hydrophobic soil amendment to a growing medium component to form a treated component that, when placed in the container and irrigated by a liquid from below the growing medium, reduces the capillary action of the growing medium and impedes the transport of the liquid into the growing medium compared to the growing medium having the same amount of growing medium component without the hydrophobic soil amendment applied to the growing medium component; and forming the growing medium from at least the treated component.

42. The method of claim 41, further comprising: adding the treated component into the container in a sub-surface layer of the growing medium; and covering the treated component with a layer of growing medium that does not contain the hydrophobic soil amendment.

43. The method of claim 41, further comprising adding the treated component into the container such that the treated component is distributed throughout the entire thickness of the growing medium in the container.

44. The method of any one of claims 41 through 43, wherein applying the hydrophobic soil amendment makes the treated component fully hydrophobic, the method further comprising: mixing the treated component with a second growing medium component to form a partially-hydrophobic growing medium.

45. The method of claim 44, wherein a ratio by weight of the treated component to the second growing medium component has a value in a range from 5:95 to 95:5.

46. The method of claim 44, further comprising dehydrating the partially-hydrophobic growing medium.

47. The method of any one of claims 41 through 43, wherein applying the hydrophobic soil amendment comprises: diluting a liquid hydrophobic soil amendment to form a diluted liquid soil amendment; and applying the diluted liquid soil amendment to the growing medium component.

48. The method of claim 47, wherein a ratio by weight of the diluted liquid soil amendment to the growing medium component has a value in a range from 5:95 to 95:5.

49. The method of claim 47, wherein applying the diluted liquid soil amendment to the growing medium component hydrates the growing medium component from a dehydrated and compressed state.

50. The method of claim 47, further comprising: dehydrating the growing medium after applying the hydrophobic soil amendment to the growing medium component.

51. A system for growing at least one crop with a sub-irrigation system, the system comprising: a container having at least one cell in which a plant can grow; at least one opening in a base of the at least one cell to allow ingress of liquid from the sub -irrigation system; and growing medium within the at least one cell, wherein the growing medium comprises: a growing medium component; and a hydrophobic soil amendment applied to the growing medium component to form a treated component that reduces the capillary action of the growing medium and impedes the transport of the liquid into the growing medium, when irrigated by the liquid from below the growing medium, compared to the growing medium having the same amount of growing medium component without the hydrophobic soil amendment applied to the growing medium component.

52. The system of claim 51, wherein the treated component is located in a sub-surface layer of the growing medium.

53. The system of claim 51, wherein the treated component is distributed throughout an entire thickness of the growing medium within the at least one cell.

54. The system of any one of claims 51 through 53, wherein the container is configured to float on the liquid while containing the growing medium.