Continuous cultivation of plants

Abstract

The present invention relates to a method of cultivating a plant, comprising the steps of suspending a plant comprising a stem and a root portion, said plant being suspended freely by the top of said stem, said root portion hanging freely from said stem in a substantially enclosed root compartment in the absence of a growing medium; watering said plant, e.g. by providing water containing nutrients and / or oxygen to said plant, i.e. to said root portion in said root compartment; and lowering said plant after growing said plant, said steps comprising the steps of: suspending said plant freely by the top of said stem, said root portion hanging freely from said stem in a substantially enclosed root compartment in the absence of a growing medium; watering said plant, e.g. providing water containing nutrients and / or oxygen to said plant, i.e. to said root portion in said root compartment; after the step of lowering the plant so that a bottom portion of the stem hangs freely into the root compartment and growing new roots at the bottom of the stem in the root compartment, the step of lowering the plant includes a step of re-suspending the plant by the new growth of the stem, i.e., the new growth of the stem that is above the top of the stem; pruning at least a portion of the roots at the bottom end; and repeating the steps of lowering the plant and pruning the roots each time the plant is grown.

Description

[Technical field]

[0001] The present invention relates to a method for cultivating plants, for example a method for continuously cultivating plants in a greenhouse. The present invention further relates to a cultivation assembly, a root growth promoter and an indoor farm for target plants. [Background technology]

[0002] During normal growth of plants, especially in greenhouses, such as tomatoes, peppers, cucumbers, and eggplants, the length of the plant's stem increases over time. The new growth of the plant usually grows leaves and produces at some point along the stem, but the stem itself continues to grow, so that when the crop is harvested, new stems grow above the harvested crop. As a result, the length of the stem between the roots of the plant and the crop increases over time, resulting in efficiency losses and eventually the plant will stop producing. Thus, it requires more energy for the plant to transport nutrients from the roots to the crop, which is impractical; i.e., the excess stems need to be accommodated in the greenhouse.

[0003] Prior art PCT application WO 01 / 97599 A2 discloses a cultivation system comprising a movable support wire extending in a loop adapted to be fixed to a plant. The plant is guided by the support wire with its stem substantially upright and its roots lying in the water supply tube. During the growth of the plant, the support wire moves and the stem drops so that the excess of the roots now lies on the inclined part above the water supply tube. This upward inclination, under the influence of gravity, forces any hormones towards the newly lowered horizontal part of the stem, which eventually ends up with its bottom end, i.e. including the oldest roots, protruding from the water supply tube. This allows the stem to grow further along the vertical part of the support wire and allows the bottom of the stem to develop new roots in the water supply tube, e.g. allowing the excess roots to be pruned. In this way, the net length of the plant, i.e. including the stem and roots, remains substantially constant, effectively resulting in a continuous renewal of the plant.

[0004] A second example of such a continuous growth cultivation system is disclosed in Jan Janse et.al. "Ontwikkeling continuteelt komkommer (2005)", Praktijkonderzoek plant omgeving, Wageningen UR. This scientific publication discloses a similar system, in which the cucumber plants are partially suspended from the roof of the greenhouse and the roots of the plants are partially suspended in and out of a spray trough that is held in an arc while being sprayed. Also in this disclosure, the lower end of the roots is held upwards, so that the hormone flows down the arc, i.e., towards the stem.

[0005] However, these known assemblies have the drawback of being relatively complex as a result of the horizontal water supply pipe feed and the support wire loops, both of which are relatively voluminous, for example, compared to conventional cultivation systems. Secondly, the systems have several moving parts, especially due to the support wire guides and the movement mechanism. This makes it difficult to install the known assemblies in existing greenhouses. Furthermore, these systems are labor intensive, requiring manual labor to lower the plants and cut the roots.

[0006] SE 424 399 B discloses a method of cultivation in which plants are suspended and sprayed with their roots suspended in a closed channel. The channel comprises a number of upper openings through which the plant stems can extend during plant growth. Furthermore, this prior art document teaches that the plants can first be cultivated in a conventional manner with their roots placed in soil, i.e. in a moisture absorbing ball. Only after a certain time can the plants be placed with their roots in the enclosed channel. Moreover, in this existing cultivation method, the positions of the plants are strictly limited by the upper openings of the closed channel, and each plant position is provided with two dedicated spray nozzles to supply water and nutrients to the plants. Summary of the Invention [Problem to be solved by the invention]

[0007] It is therefore an object of the present invention to provide a cultivation method and assembly which is more convenient to operate and install than existing methods and systems, or which at least provides an alternative cultivation method and assembly. [Means for solving the problem]

[0008] The present invention relates to a method of growing plants, e.g. a method of growing plants in a greenhouse, comprising the steps of suspending a plant comprising a stem and a root portion, said plant being suspended freely by the top of said stem, said root portion hanging freely from said stem in a substantially enclosed root compartment, e.g. in the absence of a growth medium; watering said plant, e.g. watering said plant with water comprising nutrients and / or oxygen, i.e. watering said root portion in said root compartment; and lowering said plant after growing said plant. the step of lowering the plant including a step of re-suspending the plant by the new growth of the stem, i.e., the new growth of the stem that is above the top of the stem, after the step of lowering the plant so that the bottom of the stem hangs freely into the root compartment and growing new roots at the bottom of the stem in the root compartment; pruning at least a portion of the roots at the bottom end; and repeating the steps of lowering the plant and pruning the roots each time the plant is grown.

[0009] The method is configured to grow the plants continuously and substantially straight and vertically, so that the length of the plant, i.e. the length of the stem, is substantially the same each time the plant is lowered, i.e. after it has been partially lowered into the root compartment. The method is particularly efficient in greenhouse cultivation, where there is a greenhouse roof structure above the plant from which the plant can be suspended. The plant may be suspended from a wire, such as a metal wire, or any other support structure.

[0010] The plants grown in this manner comprise a stem and a root. Thus, the stem of a plant may be defined as the part of the plant that is substantially free of roots, but rather produces roots and has leaves attached thereto, while the root may be defined as the part that includes the roots, e.g., produces stems, leaves, and lateral branches contained in the plant, is pruned, and develops root growth under the influence of certain conditions, e.g., humidity, low light levels, and oxygen levels.

[0011] When the method is performed, the roots are located in the root compartment, while the stem is located outside the root compartment, e.g., above the root compartment. The method is particularly useful for growing plants that have a relatively long stem compared to the length of the plant roots, such as tomatoes, peppers, cucumbers, and / or eggplants, and plants that can form roots in the stem under certain conditions, such as humidity, low light levels, and oxygen levels.

[0012] Contrary to existing methods, in this method the plants are freely suspended, meaning that substantially the entire plant is suspended under the influence of gravity, without at least partially resting horizontally, without being placed in any type of root growth medium and preferably without the roots being supported separately by the root compartment, i.e. thus suspended substantially vertically.

[0013] The plant is held at the top, e.g., at one or more points at the top of its stem. The top of the stem may be defined as the top 25% of the stem in terms of height. However, the plant does not have to be held only at the top, but may additionally be held at, e.g., the middle and / or bottom.

[0014] Free hanging of a plant produces a plant that is substantially completely self-supporting, such that all parts of the plant below the top, e.g., the middle and bottom of the stem, and at least a portion of the root, hang completely down from the top and are otherwise substantially unsupported in a vertical direction.

[0015] The roots of the plant are suspended in the root compartment, preferably freely suspended, so that the roots are also completely suspended from the stem without being supported in any other way. The root compartment is substantially closed from the surroundings, for example only including a single opening at the top through which the plant can grow. The root compartment is substantially empty, meaning that the plant roots are not placed in any type of growing medium such as soil, rock wool, etc., but instead the plant roots hang freely in the air inside the root compartment. The plant roots may hang vertically in the root compartment. However, if the length of the roots is relatively long compared to the height of the root compartment, the bottom of the roots may be tied to the plant stem to prevent the bottom of the roots from contacting the bottom of the root compartment.

[0016] In the root compartment, water containing nutrients may be supplied to the plant roots. This nutrient supply may include supplying water to be absorbed by the roots, i.e. combined with nutrients, oxygen, fertilizers, etc. Supply may include spraying of water with nutrients to the roots, which may rely on droplets having different sizes, e.g., small to large droplet sizes resulting in atomization or generation of a mist to provide some degree of direct penetration by the water of the plant. In one embodiment, the size, i.e., diameter, of the droplets may range from 20 μm to 80 μm.

[0017] Alternatively, the watering may include temporarily submerging the roots in a body of water that contains particular nutrients. In addition to the water, oxygen may be actively supplied to the water, for example by bubbling, to provide additional oxygen and turbulence to the submerged roots. As a further alternative, the watering may involve dripping the roots, for example by releasing water droplets into the internal volume of the root growth promoter that is filled by the roots.

[0018] Plants can grow under the influence of nutrients, for example under exposure to light.During growth, plants can form new shoots of stems on top of the top, so that this first top becomes the previous top, and then the new shoot becomes the top.Furthermore, growth can concern the growth of roots inside the root compartment, for example, in terms of root size and / or new root formation, and can concern the growth of crops, leaves and shoots.

[0019] After growing the plant, the length of the stem will increase. In order to keep the length of the stem substantially constant, the plant is lowered after some growth. Lowering means that the hanging of the plant changes and the plant droops. Therefore, the bottom of the root is pruned.

[0020] After the step of lowering, the bottom of the stem becomes free to hang in the root compartment, i.e., hangs from the stem of the plant located above the root compartment. Thus, the root compartment is not lowered with the plant and therefore remains substantially stationary. After lowering, the bottom of the stem and the original root are united to become the new root, and the new bottom of the stem is defined just above the root compartment.

[0021] The original bottom part of the stem, now located in the root compartment, is exposed to water, for example with nutrients and / or oxygen, thereby developing new roots. Thus, the plant may automatically develop new roots where the environment is moist and the light level, i.e., light intensity, is relatively low. In particular, new roots may form in the dark, i.e., in the absence of light.

[0022] After descending and waiting for a certain time, the original base of the stem, i.e. together with its new roots, forms the original root part of the plant, the inner root part of the root compartment. It is thus noted that the definition of which part of the plant belongs to the root part changes each time the plant descends.

[0023] The descent of the plant refers to the release of the plant from its original suspension, i.e. the plant is suspended from its original top. After release, the plant descends and hangs again. However, the plant is now suspended at least in part by the newly grown growth, i.e. the stem of the plant, being above the original top. As a result, this growth is by definition the topmost part of the stem. It should be noted that the entire plant is not necessarily suspended by the new growth, but may be suspended by a combination of both the new growth and the original top.

[0024] Pruning is done to prevent the roots from growing too large inside the root compartment, so that after lowering, the length of the part of the plant inside the root compartment will be larger. Pruning therefore involves pruning the bottom of the roots, so that the new root length is substantially the same as the original root length, i.e., before lowering.

[0025] Pruning can be manual or automatic, but within the meaning of the invention it is always carried out as an active step during which part of the root is removed, which differs, for example, from prior art growing methods in which the base of the root is killed, i.e. in the absence of water, and only then cut.

[0026] Finally, these steps are repeated, i.e., the plant is allowed to grow while being watered, followed by lowering and root pruning. In this way, the plant is allowed to continuously "refresh" itself while having substantially the same length, e.g., the combined length of stem and root, each time the plant is lowered and pruned. However, alternatively, the plant can be maintained at a constant length that suits the current and / or future needs of the plant. This length may change over time, e.g., due to seasonal effects, and can be selected for each repetition of the steps.

[0027] The present invention offers the advantage that the plant footprint can be significantly smaller than that of the prior art plants as a result of the plants being completely hung vertically instead of having a horizontal configuration. As a result of this smaller footprint, the risk of entanglement of the roots of two adjacent plants is minimized, since the roots of each plant are located only below the stem and do not extend substantially to the sides.

[0028] The present invention offers the surprising advantage that it is not essential that the roots be in contact with a growing medium, or even with water as in the prior art methods of hydroponics.

[0029] The ability to grow without a growing medium allows the plant to hang freely, so that it can essentially completely support its own weight, which is very difficult to do if the plant is grown in a growing medium, as the plant's stem would likely not be able to support the additional weight of the growing medium, and the growing medium would require constant replenishment with each cycle the plant descends.

[0030] The present invention is more intuitive for those skilled in the art because the above-mentioned prior art documents teach that hormones flow under the influence of gravity, and the lower end of the root dies. Due to this prejudice, the skilled person would never hang the plant vertically under its own weight, because they would assume that gravity would cause hormone accumulation at the bottom end. The present inventors have surprisingly found that this gravity-based hormone descent does not occur in the present invention.

[0031] However, the main advantage of plants being suspended vertically under their own weight is the convenience of being able to move them around, for example in a greenhouse, etc. Thus, the plants only have a free hanging root portion that hangs straight down below the support structure and is not located in a bulky, heavy plant pot or substrate.

[0032] Furthermore, the plant is not attached to the root compartment, but is merely suspended therein. Preferably, the roots are substantially free hanging in the root compartment, but instead, a portion of the roots may be present on the bottom wall of the root compartment. In the absence of such attachment, as in the prior art, it is not necessary to move the plant, to replace the support of the roots inside the root compartment, or to detach the roots from the loop wire that runs through the root compartment, if desired. Instead, the plant support structure can simply be moved, for example via a rail system, trolley and / or motorized carriage, while the roots move out of the root compartment, while the plant follows the movement of the support structure.

[0033] Furthermore, the method according to the invention cultivates the plant in the absence of a growth medium around the roots throughout substantially the entire life cycle of the plant. Thus, the plant seed is initially inserted into the vermiculite to initiate root growth. However, as soon as the roots begin to develop, the seed is removed from the vermiculite and placed in the root compartment. This differs from existing cultivation methods in which the plant seedlings are initially cultivated in soil, i.e. in wicking balls, and the soil is only removed at a later stage. This may provide the advantage that the method results in less waste, since no soil or other growth medium is utilized. Furthermore, the method may provide less stress to the plant, since it is no longer subject to changes in conditions, i.e. from cultivation in soil to soilless cultivation.

[0034] Finally, the method may rely on fewer spray nozzles than existing cultivation methods. Thus, according to the present invention, the location of the plants does not necessarily have to be defined at a separate, fixed location. Instead, the location of the plants may vary and each spray device may have a relatively wide spray range, thereby allowing multiple different plants to be sprayed inside the root compartment. The present invention essentially decouples the location of the plants from the spray device, which provides improved flexibility of the cultivation system, allows for use for multiple different types of plants, and provides mobility for the plants.

[0035] In one embodiment, the method further comprises the step of harvesting the horticultural crop from the stem after growing the plant, e.g., prior to the step of lowering, whereby the step of repeating comprises repeating the steps of harvesting, lowering, and root pruning.

[0036] According to this embodiment, the crop is harvested at each cycle of drop and root pruning, since the crop usually grows when the stem of the plant is allowed to grow. Similarly, when the crop is harvested, any leaves and shoots may be cut off from the stem of the plant. Thus, these leaves and shoots would otherwise absorb nutrients, thus reducing the yield of the plant.

[0037] However, instead, no harvesting takes place between each repetition, which may be the case if the duration of plant growth, for example to reach a threshold level of stem growth in a cycle, is shorter than the duration of crop growth and / or grain filling.

[0038] In an embodiment of the method, the hanging step further comprises clamping the top of the stem with at least one clamp of a support structure, which may, for example, comprise two or three clamps positioned on top of each other to hold the top of the plant together.

[0039] The advantage of having a clamp is that the plant can be held securely since the entire weight of the plant is hanging from it, while avoiding disturbing the flow of nutrients in the plant. Furthermore, the clamp is relatively convenient to install, for example by a human worker or a robot, so that the hanging of the plant can be performed efficiently.

[0040] In a further embodiment of the method, the lowering step includes releasing the at least one clamp and re-clamping the stem growth with the at least one clamp.

[0041] Lowering may thereby involve releasing the clamp at an original position at the original apex of the plant stem, lowering after release, and releasing the clamp at a new position on the plant stem, i.e., new growth above the original apex.

[0042] According to this embodiment, if the clamping is performed with multiple clamps, one of the clamps can clamp the new growth of the stem, while another of the clamps still clamps the original top of the stem, but instead clamps its higher part, but alternatively both clamps can clamp the new growth of the stem after descent.

[0043] In one embodiment of the method, the step of watering comprises spraying the plant in the root compartment with water, for example with nutrients and / or oxygen.

[0044] Thereby, a spraying device configured to spray the roots with water can be provided inside the root compartment. The spraying of the roots can be sufficient to expose the roots to the required amount of water, which can render the roots obsolete to be submerged in water. The spraying can rely on droplets having a variety of sizes, from small droplet sizes that effectively mist or fog the spray, to large droplet sizes, for example to affect a certain degree of direct penetration of the roots with water. In one embodiment, the size, i.e., diameter, of the droplets can range from 20 μm to 80 μm.

[0045] An additional benefit of spraying is that mist water may be present in the root compartment and that the humidity in the root compartment may be higher than the surroundings outside the root compartment, i.e., around the stem of the plant. This higher humidity may promote the formation of new roots at the base of the plant stem just down into the root compartment and may also promote the growth of existing roots in the root compartment.

[0046] In an embodiment of the method, spraying may include spraying multiple plants with a single spray device. The method according to this embodiment may rely on fewer spray nozzles than existing cultivation methods. Thus, according to this embodiment, the location of the plants does not necessarily need to be defined at individual locations. Instead, the locations of the plants may vary and each spray device may have a relatively wide spray range, thereby allowing multiple different plants to be sprayed inside the root compartment.

[0047] In an embodiment of the method, the spraying of water is performed intermittently for a spray duration, with subsequent spraying episodes separated by a pause duration.

[0048] According to this embodiment, the spraying is not performed continuously, but during a certain discrete spraying interval. The spraying can be performed for a certain spraying time, for example, a spraying time ranging between 1 second and 10 minutes, such as a spraying time of about 1 minute. After each spraying action, i.e., when the spraying time is over, the spraying can be paused for a certain pause time, for example, a pause time ranging between 1 second and 10 minutes, such as a pause time of 4 minutes.

[0049] In that sense, the nebulization ratio may be defined as the percentage of time that nebulization is performed. For the exemplary values ​​above, the nebulization ratio is 1 minute out of every 5 minutes, thus 20%.

[0050] In one embodiment, the method includes measuring an input mass flow rate of water supplied towards the spraying device after being sprayed onto plant roots in the root compartment, and measuring an output mass flow rate of water exiting the root compartment, the input mass flow rate and the output mass flow rate may be different from each other, the difference of which may represent the total amount of water absorbed by the plant roots.

[0051] In a further embodiment, the water supply towards the spraying device, i.e. the supply mass flow rate, can be controlled based on the difference between the supply mass flow rate and the discharge mass flow rate. In that way, the water supply towards the plant roots can be minimized to the amount of water actually absorbed by the plant roots. This can reduce the water runoff and reduce the consumption of energy required to pump water towards the spraying device.

[0052] In one embodiment of the method, the root compartment is substantially opaque, in particular substantially opaque to light in the visible and ultraviolet spectrum.

[0053] The inventors have found that opaque root compartments, i.e., those with relatively low light levels, provide improved conditions for the formation of new roots and the growth of existing roots. Particularly in the absence of light, i.e., in the dark, the formation of new roots may be promoted. When the bottom of the stem is lowered into the root compartment, i.e., during each stage of descent, it is not only provided with water, but is also subjected to an environment that promotes root growth. In this sense, the formation of new roots is promoted, but also the growth of the remaining roots, for example after pruning, is promoted so that the roots can return faster to their initial root volume.

[0054] In one embodiment of the method, the pruning step includes pruning the bottom end of the root section over a height substantially equal to the height to which the plant is lowered. According to this embodiment, the total length of the root section remains substantially the same before and after lowering and root pruning. Thus, the bottom of the stem is lowered into the root compartment for a height, which is equal to the height of the root section to be cut off.

[0055] In one embodiment of the method, the root portion is at least partially tightly surrounded by a peripheral root growth promoter, which is preferably supported exclusively under the influence of an outward clamping force acting on the root growth promoter about the periphery of the root portion.

[0056] The root growth promoter is configured to surround the root of the plant and form a lateral restriction for the growth of the root. The root, i.e., the part of the stem that includes the bottom that descends into the root compartment, is surrounded by the root growth promoter on the side, for example horizontally. The root may be in contact with the root growth promoter, but the root growth promoter may be distant from the stem. The root growth promoter is configured to physically block the lateral growth of the root. Thus, the root of the plant is usually less likely to develop when it encounters a physical barrier. In this way, root pruning can remove a certain amount of roots each time, resulting in better plant balance and production, minimizing shock and stress to the plant, and preventing the dominant root zone of the root from growing too large.

[0057] Instead, the plant will develop and grow roots in places where there are no roots, e.g., places that are not yet restrained by the root growth promoter. Thus, the plant will have extra motivation to grow roots at the bottom of the stem, down into the root compartment, because the root growth promoter is away from the stem and thus not yet preventing root growth.

[0058] Apart from promoting uniform root growth, root growth promoters can confine the roots of a plant to avoid entanglement of the roots of several different plants, for example during movement of the plants.

[0059] As a further advantage, the root growth promoter may form a fixed reference point at certain processing stations for the plants, such as inspection and / or harvesting stations, where the plants can be held by their root growth promoter, which is uniform for each plant, allowing for a more secure grip compared to when the roots themselves are gripped.

[0060] The root growth promoter preferably sags at the root and is not supported by any other means. This sagging can occur due to contact between the root and the root growth promoter. Thus, as the roots grow against the root growth promoter, they for example come together and exert pressure on the root growth promoter. This pressure can be aligned radially outward, e.g. horizontally, as seen against the vertical direction in which the stem grows. This pressure therefore results in a clamping effect on the outside of the root growth promoter, thereby ensuring full support of the root growth promoter.

[0061] Alternatively, the root growth promoter may be provided with an annular clamp flap at its apical end, e.g. a truncated cone flap made of a flexible material such as rubber, to suspend the root growth promoter from the root section. The clamp flap may be configured to clamp a part of the root section, e.g. the bottom of the plant stem, under the influence of gravity acting on the root growth promoter. However, the clamp flap may allow upward movement of the root growth promoter when counteracting gravity to allow convenient shifting of the root growth promoter.

[0062] According to this embodiment, the root growth promoter may not include any other suspension means, in this way the plant is suspended to support not only its own weight but additionally the weight of the root growth promoter.

[0063] In a further embodiment of the method, the root growth promoter comprises a peripheral wall defining a through passage along the longitudinal axis and one or more side openings providing access to the through passage in one or more transverse directions perpendicular to the longitudinal axis.

[0064] According to this embodiment, the peripheral wall can form a physical barrier to prevent root growth, while the side openings in the peripheral wall can allow the passage of water and nutrients so that they can be received by the roots restricted to the root growth promoter.

[0065] In alternative or additional embodiments of the method, the peripheral wall of the root growth promoter extends along the long axis for a length substantially equal to the length of the root portion, ie perpendicularly.

[0066] According to this embodiment, substantially the entire root is contained in the root growth promoter. In that way, the growth of existing roots in the original root can be restricted, while the root growth promoter allows the growth of new roots at the bottom of the stem that has just been lowered into the root compartment. Thus, this bottom of the stem also forms part of the root after descent, and is therefore also restricted by the root growth promoter.

[0067] In alternative or additional embodiments of the method, the lowering step further comprises shifting the root growth promoter upwardly relative to the plant over a height substantially equal to the height to which the plant has been lowered, such that the bottom of the stem in the root compartment becomes at least partially surrounded by the root growth promoter.

[0068] Each time the plant descends, according to this embodiment, the root growth promoter shifts upwards, thus causing the bottom part of the stem, which is just lowered into the root compartment and will form part of the root, to become surrounded by the root growth promoter and ultimately restricted from growing roots.

[0069] As a result of the upward shift of the root growth promoter, the bottom end of the root may become exposed below the root growth promoter, but this bottom end of the root is not of any practical use and is usually pruned off before or after the plant has dropped.

[0070] In one embodiment, the method further comprises the step of scrutinizing, e.g. optically scrutinizing, one or more parameters of the plant. Scrutinizing can be performed autonomously, e.g. optically by one or more cameras, to obtain knowledge about the physical state of the plant.

[0071] Typically, parameters that may be examined may be, but are not limited to, plant length, leaf size and / or number, crop presence and / or ripeness, and the like.

[0072] In an embodiment of the method, the steps of lowering, root pruning, inspection and / or harvesting are performed in one or more respective stations, e.g., respective lowering stations, root pruning stations, inspection stations and / or harvesting stations, which are located away from the cultivation location, which may be the location where the plants are placed once they are allowed to grow, e.g., in the root compartment. The stations, according to this embodiment, are not located at the cultivation location, but are located in a different location of the greenhouse, e.g., a centralized processing location.

[0073] According to this embodiment, the method further comprises the steps of: lowering, pruning, inspecting and / or harvesting are performed at one or more respective stations located away from a cultivation location; moving the plant from the cultivation location to the station prior to the lowering, pruning, inspecting and / or harvesting steps; and moving the plant from the station to the cultivation location after the lowering, pruning, inspecting and / or harvesting steps.

[0074] To allow inspection, lowering, root pruning and / or harvesting to take place at a remote station, the plants are transported there and then returned to the growing site. This transport is possible because the plants are freely suspended above and below by their own weight. Thus, the plants only have a free hanging root part that hangs straight down below the support structure and is not located in a bulky and heavy plant pot or substrate.

[0075] In a further embodiment of the method, the plants are suspended from a movable support structure, which may, for example, comprise one or more wheels or rollers and engage with a rail system. Alternatively, the movable support structure may comprise a suspended chain from which the plants may be suspended, or any other system from which the plants may be suspended in a mobile manner.

[0076] The movable support structure is configured to move either actively, e.g., by an internal actuator or motor, or passively, by an external actuator, e.g., attached to a driven conveyor or chain. The movable support structure can simply move, e.g., via a rail system, trolley, and / or motorized carriage, while the plant roots move out of the root compartment, while the plant follows the movement of the support structure.

[0077] In one embodiment, the step of suspending the plant relates to suspending the seedling when no growth medium is present. According to this embodiment, the plant is cultivated without a growth medium around the roots throughout the entire life cycle of the plant. This differs from existing cultivation methods in which the plant seedling is cultivated in soil initially and the soil is only removed at a later stage. This may provide the advantage that the method according to this embodiment may result in less waste since no soil or other growth medium is utilized. Furthermore, the method may provide less stress to the plant since it is no longer subject to a change in conditions, i.e., from cultivation in soil to soil-free cultivation.

[0078] According to a second aspect, the present invention provides a cultivation assembly for carrying out the method described above, comprising a support structure configured to suspend the stem of the plant, a substantially enclosed root compartment configured to receive the roots of the plant, and a watering device arranged at least partially in the root compartment and configured to supply the water, e.g. the nutrients and / or the oxygen to the plant, i.e. to the roots.

[0079] The cultivation assembly may be provided in a greenhouse and may then be used to grow plants such as tomatoes, peppers, cucumbers and / or eggplants, which in greenhouse cultivation are able to form roots in the stems under certain conditions such as humidity, low light levels and oxygen levels.

[0080] The support structure is configured to hold the plant, e.g., to hold the plant substantially stationary during growth, such that one part of the plant, i.e., the stem, is thereby exposed to light, while another part of the plant, e.g., the roots, hangs down into the root compartment, whereby the root compartment is located below the support structure.

[0081] The watering device is arranged inside the root compartment and is configured to supply water to the roots of the plant. The supply of nutrients may include supplying water, i.e., water combined with nutrients, oxygen, fertilizers, hormones, and / or pesticides, etc., for absorption by the roots. The watering device may be configured to spray the water with nutrients onto the roots or may be specifically configured to temporarily submerge the roots with nutrients in a body of water.

[0082] A cultivation assembly according to the present invention may include one or more of the features exemplified herein in view of the cultivation method according to the present invention and / or may have one or more of the benefits exemplified herein in relation to the cultivation method.

[0083] In an embodiment of the growing assembly, the support structure includes at least one clamp configured to clamp a stem of a plant. The at least one clamp may be fixedly connected to a frame portion of the support structure or may be attached, for example, to a rope or chain that is suspended to support the plant.

[0084] The support structure may, for example, comprise two or three clamps arranged on top of one another that are configured together to hold the top of the plant.

[0085] The advantage of having a clamp is that it can hold the plant securely, since the entire weight of the plant is hanging from it, while avoiding disturbing the flow of nutrients in the plant. Furthermore, the clamp is relatively easy to install, for example by a human worker or a robot, so that the hanging of the plant can be performed efficiently.

[0086] In an embodiment of the cultivation assembly, the root compartment is substantially opaque, in particular substantially opaque to light in the visible and ultraviolet spectrum.

[0087] The inventors have found that opaque root compartments, i.e., those with relatively low light levels, provide improved conditions for the formation of new roots and the growth of existing roots. Particularly in the absence of light, i.e., in the dark, the formation of new roots may be promoted. When the bottom of the stem is lowered into the root compartment, i.e., during each stage of descent, it is not only provided with nutrients, but is also subjected to an environment that promotes root growth. In this sense, the formation of new roots is promoted, but also the growth of the remaining roots, for example after pruning, is promoted so that the roots can return to their initial size more quickly.

[0088] In an embodiment of the cultivation assembly, the root compartment comprises a substantially enclosed trough and is configured to receive the roots of a plurality of plants arranged in a row extending parallel to the trough.

[0089] Such a trough allows the placement of multiple roots of multiple different plants in the same root compartment, i.e., in the same trough, which may be hung, for example, in vertical rows in a greenhouse aisle, each row parallel to its own trough.

[0090] The substantially enclosed trough may include a slit at its top, which may be relatively narrow compared to the width of the trough, i.e. the width perpendicular to the longitudinal direction of the trough, through which the plants enter the trough. The advantage of having only a narrow slit is that the climate of the trough, e.g. a moist climate with relatively low light levels, may be more effectively maintained to obtain optimal growing conditions for the roots.

[0091] This trough is particularly useful when moving plants through, for example, a greenhouse, because the plants may be moved along, for example, a row, so that their roots are in the trough for a long period of time, as compared to when they should each be kept in an individual root compartment for a single plant.In particular, the plant stems may be moved through the slits as they are moved towards the central aisle of the greenhouse.

[0092] Furthermore, the trough may provide an advantage over existing cultivation assemblies having separate root compartments with top openings in that the position of the individual plants does not need to be precisely defined. Thus, in existing cultivation assemblies, each plant must be placed in its own top opening, which fixes the position of the plant. With the trough, the plants can be placed anywhere along the length of the slit. This provides the possibility to be able to adjust the mutual distance between the plants, improving the flexibility of the cultivation assembly and making it possible, for example, to cultivate different types of plants and to cultivate the plants at different densities, i.e. mutual distances.

[0093] In one embodiment of the growing assembly, the watering device comprises a spraying device configured to protrude into the root compartment and to spray, for example, nutrients onto the roots of the root compartment, the spraying of the roots being sufficient to expose the roots to the required amount of water and nutrients, which may render the roots obsolete to be submerged in water.

[0094] The advantage of spraying is that mist water may be present in the root compartment, and the humidity in the root compartment may be higher than the surroundings outside the root compartment, i.e., the surroundings of the plant stem. In addition, spraying can wet the roots and provide oxygen to the roots. All of this may promote the formation of new roots at the bottom of the plant stem that just dropped into the root compartment, and may also promote the growth of existing roots in the roots.

[0095] In a further embodiment, each spraying device is configured to spray multiple plants in the root compartment. The method according to this embodiment can rely on fewer spray nozzles than existing cultivation methods. Thus, according to this embodiment, the location of the plants does not necessarily have to be defined at individual locations. Instead, the locations of the plants may vary and each spraying device may have a relatively wide spray range, thereby allowing multiple different plants to be sprayed inside the root compartment.

[0096] This embodiment may be particularly beneficial when the root compartment is embodied as a trough with a slit at its top. The trough allows the plants to be placed anywhere along the length of the slit, eliminating the need to place each plant at its own top opening. Furthermore, this embodiment offers the advantage that each spraying device has a large spray range and therefore can cover multiple plants, without the need to precisely position the plants in front of the spraying devices, as in the prior art.

[0097] In one embodiment, the cultivation assembly is configured to measure an inlet mass flow rate of water supplied towards the spraying device and an outlet mass flow rate of water pumped out of the root compartment after being sprayed onto the plant roots inside the root compartment, the inlet mass flow rate and the outlet mass flow rate may be different from each other, and this difference may represent the total amount of water absorbed by the plant roots.

[0098] In a further embodiment, the cultivation assembly may be configured to control the water supply, i.e. the supply mass flow rate, towards the spraying device based on the difference between the supply and discharge mass flow rates. In that way, the water supply towards the plant roots may be minimized to the amount of water actually absorbed by the plant roots. This may reduce water runoff and reduce the consumption of energy required to pump water towards the spraying device.

[0099] In one embodiment, the cultivation assembly further includes a plant, such as a tomato, pepper, cucumber and / or eggplant, or a plant capable of forming roots in the stem under certain conditions, such as humidity, low light levels, and oxygen levels, comprising a stem and a root portion, the plant hanging freely from the support structure by the stem tip and the root portion hanging freely from the stem, e.g., in the absence of a growing medium, in the root compartment.

[0100] Contrary to existing cultivation assemblies, the plants in the cultivation assembly according to the present embodiment are configured to be freely suspended, meaning that substantially the entire plant is suspended under the influence of gravity, i.e. suspended substantially vertically, without at least partially resting horizontally and preferably without the roots being supported separately by a root compartment.

[0101] The plant is held at the top and configured to fully support its own weight. Thus, all parts of the plant below the top, e.g., the middle and bottom of the stem, at least a portion of the root, hang completely down from the top and are otherwise substantially unsupported in a vertical direction. However, the plant need not be held only at the top, but may additionally be held at, e.g., the middle and / or bottom.

[0102] The roots of the plant are suspended in the root compartment, preferably suspended freely, so that the roots are also suspended completely from the stem without being supported in any other way. The root compartment is substantially empty, meaning that the roots of the plant are not placed in any type of growth medium, such as soil, rock wool, etc., but instead, the roots of the plant hang freely in the air inside the root compartment, possibly inside a root growth promoter. However, the roots of the plant may hang vertically in the root compartment, but if the length of the roots is relatively long compared to the height of the root compartment, the bottom of the roots may be tied to the plant stem so that it does not contact the bottom of the root compartment.

[0103] In one embodiment, the cultivation assembly further comprises a root growth promoter configured to at least partially surround the root portion, the root growth promoter preferably configured to be exclusively supported under the influence of an outward clamping force acting on the root growth promoter about the periphery of the root portion.

[0104] The root growth promoter is configured to surround the root of the plant and form a lateral restriction for the growth of the root. The root, i.e., the part of the stem that includes the bottom that descends into the root compartment, is surrounded by the root growth promoter and configured to be oriented sideways, for example horizontally. The root is configured to be in contact with the root growth promoter, but the root growth promoter may be spaced apart from the stem. The root growth promoter is configured to physically block the lateral growth of the root. Thus, the roots of the plant are usually less likely to develop when they encounter a physical barrier. In this way, and by root pruning, a certain amount of roots is removed each time, minimizing shock and stress to the plant, resulting in better plant balance and production, and the dominant root zone of the root can be prevented from growing too large.

[0105] Instead, the plant will develop and grow roots in places where there are no roots, e.g., places that are not yet restrained by the root growth promoter. Thus, the plant will have extra motivation to grow roots at the bottom of the stem, just down into the root compartment, because the root growth promoter is away from the stem and thus not yet preventing root growth.

[0106] Apart from promoting uniform root growth, root growth promoters can confine the roots of a plant to avoid entanglement of the roots of several different plants, for example during movement of the plants.

[0107] As a further advantage, the root growth promoter may form a fixed reference point at certain processing stations for the plants, such as inspection and / or harvesting stations, where the plants can be held by their root growth promoter, which is uniform for each plant, allowing for a more secure grip compared to when the roots themselves are gripped.

[0108] The root growth promoter may preferably be configured to sag at the root portion, so that it is not supported by any other means. This sagging may occur due to contact between the root portion and the root growth promoter. Thus, as the roots grow against the root growth promoter, they may, for example, come together and exert pressure on the root growth promoter. This pressure may be aligned radially outward, e.g., horizontally, as seen relative to the vertical direction in which the stem extends. This pressure thus results in a clamping effect on the outside of the root growth promoter, thereby ensuring full support of the root growth promoter.

[0109] Alternatively, the root growth promoter may be provided with an annular clamp flap at its apical end, for example a truncated cone flap made of a flexible material such as rubber, to suspend the root growth promoter from the root. The clamp flap may be configured to clamp a part of the root, for example the bottom of the former stem of the plant, under the effect of gravity acting on the root growth promoter. However, the clamp flap may allow for an upward movement of the root growth promoter, i.e. when countering gravity, to allow convenient shifting of the root growth promoter.

[0110] According to this embodiment, the root growth promoter may not include any other suspension means, in this way the plant is not only configured to support its own weight by being suspended, but additionally also supports the weight of the root growth promoter.

[0111] In a further embodiment of the cultivation assembly, the root growth promoter comprises a peripheral wall defining a through passage along the longitudinal axis and comprising one or more side openings providing access to the through passage in one or more transverse directions perpendicular to the longitudinal axis.

[0112] According to this embodiment, the peripheral wall can form a physical barrier to prevent root growth, while the side openings in the peripheral wall can allow the passage of water and nutrients so that they can be received by the roots restricted to the root growth promoter.

[0113] An additional advantage of the side opening is that when the root growth promoter is slid upwards, the roots growing out of the side opening will either fold inwards on the root growth promoter, thereby further filling the root growth promoter or being automatically pruned. Both options may be desirable for different types of plants, and whether the first or second option occurs may depend on the shape of the opening. For example, a round shape may cause the roots to fold inwards, while a narrow vertical slit may cut off the roots as the root growth promoter slides upwards.

[0114] The peripheral wall can be viewed along the long axis and includes a cross section, which may have an enclosed hollow shape, for example, the peripheral wall may have a rectangular, e.g., square, shape, or a round, e.g., circular, shape.

[0115] Likewise, the side opening may have a shape viewed laterally, e.g. horizontally. The side opening may, for example, have a rectangular, e.g. square, shape or may have a round, e.g. circular, shape.

[0116] Additionally, the size and / or shape of the side openings of the root growth promoter may vary across its vertical length, i.e., its height. At the top of the root growth promoter, the side openings may be relatively larger to allow more water and nutrients to enter the roots at the top of the root section. At the opposing bottom of the root growth promoter, the side openings may be relatively narrower to more effectively stop root growth.

[0117] In an advantageous embodiment, the side opening may be embodied as a slit having a rectangular shape and being substantially elongated along the long axis of the root growth promoter, i.e. vertically, and relatively narrow in the vertical, i.e. horizontal, direction.

[0118] In one embodiment, the cultivation assembly further includes a lowering station, a root pruning station, an inspection station and / or a harvesting station, each configured to lower the plant onto the support structure, sever a portion of the roots, inspect one or more parameters of the plant, and harvest the crop from the plant.

[0119] In a further embodiment of the cultivation assembly, the drop station, the root pruning station, the inspection station and / or the harvesting station are located at a location remote from the cultivation location, which may be the location where the plants are placed once they have been allowed to grow, for example in the root compartment. The stations, according to this embodiment, are not located at the cultivation location, but are instead located at a different location of the greenhouse, for example at a centralized processing location.

[0120] According to this embodiment of the cultivation assembly, the support structure is configured to move plants between the cultivation location and one or more of the stations.

[0121] To allow inspection, lowering, root pruning and / or harvesting to take place at a remote station, the plants are transported there and then returned to the growing site. This transport is possible because the plants are freely suspended above and below by their own weight. Thus, the plants only hang directly below the support structure and have a free hanging root part that is not located in the pot or substrate of a bulky and heavy plant.

[0122] In a further embodiment of the growing assembly, the support structure is a mobile support structure with one or more wheels or rollers that engage with a rail system. Alternatively, the mobile support structure can comprise a suspended chain to which a hook system can be attached and from which the plants can be suspended, or any other system from which the plants can be suspended in a mobile manner.

[0123] The movable support structure is configured to move either actively, e.g., by an internal actuator or motor, or passively, by an external actuator, e.g., attached to a driven conveyor or chain. The movable support structure can simply move, e.g., via a rail system, trolley, and / or motorized carriage, while the plant roots move out of the root compartment, while the plant follows the movement of the support structure.

[0124] According to a further aspect, the present invention provides a root growth promoter for a cultivation assembly as disclosed herein, which may include one or more of the features set out herein in view of the root growth promoter described in relation to the cultivation method and / or cultivation assembly according to the present invention and / or may have one or more of the benefits set out herein in relation to the cultivation method and / or cultivation assembly.

[0125] According to yet another aspect, the present invention provides an indoor farm, in particular a greenhouse, for growing plants comprising a growing assembly as disclosed herein, wherein a support structure is attached to a roof structure of the greenhouse, the plants being advantageously configured to be suspended from the roof structure when the support structure is attached to the roof structure, for example forming part of a rail system attached to the roof structure.

[0126] In an indoor farm embodiment, the roof structure may, for example, comprise a movable support structure extending between at least the growing location and one or more of the drop-off station, the root pruning station, the inspection station and / or the harvesting station, the movable support structure comprising, for example, one or more wheels or rollers configured to be supported and rolled by a rail system or comprising a suspended chain having a hook system attached thereto. [Brief description of the drawings]

[0127] Further features of the invention will now be described with reference to embodiments thereof which are illustrated in the accompanying drawings.

[0128] [Figure 1] FIG. 1 is a schematic depiction of the steps of an embodiment of a cultivation method according to the invention. [Diagram 2] FIG. 2 is a schematic depiction of the steps of an embodiment of a cultivation method according to the invention. [Diagram 3] FIG. 3 is a schematic depiction of the steps of an embodiment of a cultivation method according to the invention. [Figure 4] FIG. 4 illustrates diagrammatically the steps of an embodiment of a cultivation method according to the invention. [Diagram 5] FIG. 5 is a schematic depiction of an embodiment of a cultivation assembly according to the invention. [Figure 6A] FIG. 6A is a schematic depiction of various embodiments of root growth promoters according to the present invention. [Figure 6B] FIG. 6B is a schematic depiction of various embodiments of root growth promoters according to the present invention. [Figure 6C] FIG. 6C is a schematic depiction of various embodiments of root growth promoters according to the present invention. [Figure 6D] FIG. 6D is a schematic depiction of various embodiments of root growth promoters according to the present invention. [Figure 6E] FIG. 6E is a schematic depiction of various embodiments of root growth promoters according to the present invention. [Figure 7A] FIG. 7A is a schematic depiction of an embodiment of a portion of an indoor farm according to the present invention. [Figure 7B] FIG. 7B is a schematic depiction of an embodiment of a portion of an indoor farm according to the present invention. [Figure 7C] FIG. 7C is a schematic depiction of an embodiment of a portion of an indoor farm according to the present invention. [Figure 8A] FIG. 8A is a schematic depiction of an embodiment of a greenhouse according to the present invention. [Figure 8B] FIG. 8B is a schematic depiction of an embodiment of a greenhouse according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0129] Throughout the drawings, the same reference numbers are used to refer to corresponding components or components with corresponding functionality.

[0130] 1 to 4 show diagrammatically the steps of an embodiment of a cultivation method according to the present invention. The present method is carried out for cultivating a plant, indicated generally by the reference numeral 100.

[0131] The plants 100 are arranged to grow continuously and substantially straight, parallel to a vertical direction V. In this embodiment of the method, the plants 100 are suspended in the greenhouse 200 from a roof structure 201 by a support structure embodied as a wire, for example a metal wire 202.

[0132] The plant 100 cultivated by the method includes a stem 110 and a root portion 120. The stem 110 of the plant 100 is defined as the portion of the plant 100 that is substantially free of roots 121, but rather includes the crop 111 and leaves 112 associated therewith. The root portion 120 may thus be defined as the portion of the plant 100 that includes the root 121. According to the method, the root 121 forms at the original base B of the previously housed stem, producing the crop 111 and leaves 112.

[0133] The roots 120 of the plant 100 are best placed in the root compartment 10 when practicing the method, with the stem 110 positioned above the root compartment 10, as shown in FIG.

[0134] The plant 100 grown in this embodiment of the method is a tomato 100, which typically has a relatively long stem 110 compared to the length of the root portion 120 of the plant 100. Alternative plants suitable for growing with the method are peppers, cucumbers and / or eggplants, and plants that are capable of forming roots in the stem under certain conditions such as humidity, low light levels and oxygen levels.

[0135] According to this method, the plant 100 is freely hanging, meaning that the entire plant 100 is suspended under the influence of gravity acting vertically downwards. The plant 100 hangs substantially vertically, without resting horizontally, and without the roots 121 being separately supported in the root compartment 10.

[0136] The plant 100 is held at its top T, and in particular at two holding points at the top T of its stem 110. In this embodiment, the top T of the stem 110 is defined as the upper 25% of the stem 110 in terms of height.

[0137] The plant 100 fully supports its own weight because all portions of the plant 100 below the top T hang completely from the top T and are otherwise substantially unsupported in the vertical direction V.

[0138] The roots 120 of the plant 100 are suspended in the root compartment 10, which is substantially closed off from the surroundings. In the embodiment of Figures 1-4, the root compartment 10 only comprises a single opening 11 at the upper end through which the plant 100 extends. The root compartment 10 is substantially empty and the roots 121 of the plant 100 are not disposed in any type of growing medium.

[0139] The root compartment 10 is substantially opaque to light in the visible and ultraviolet spectrum. This provides for the interior of the root compartment 10 to have relatively low light levels, providing improved conditions for the formation of new roots and the growth of existing roots. New root formation may be encouraged, especially in the absence of light, i.e., in the dark.

[0140] In the root compartment 10, a spraying device 20 provides nutrient-containing water to the roots 121 of the plant 100. The spraying device 20 is configured to spray the water with nutrients to the roots 120. The spraying relies on droplets having a range of sizes, from small droplet sizes where the spray results in atomization or generation of a mist, to larger droplet sizes, for example, to provide some degree of direct penetration of the plant 100 with the water.

[0141] In an embodiment of the cultivation assembly 1 according to the invention, a spraying device 20 is provided inside the root compartment 10, the spraying device 20 being configured to spray water onto the root portion 120, as best shown in FIG.

[0142] In this embodiment of the method, the spraying of water is not continuous. Instead, the spraying is intermittent for a discrete spraying interval, the duration of the spraying. The spraying is performed for a spraying period of about 1 minute. After each spraying event, i.e., at the end of the spraying period, the spraying is paused for a rest period of 4 minutes. Thus, the spraying rate is 1 minute out of every 5 minutes, or 20%.

[0143] 1-4 show that the root portion 120 of the plant 100 is tightly surrounded by a peripheral root growth promoter 30. The root growth promoter 30 is configured to surround the root portion 120 of the plant 100 and form a lateral constraint for the growth of the roots 121 of the root portion 120. The root portion 120 is in contact with the root growth promoter 30, which is configured to physically block the lateral growth of the roots 121. Instead, the plant 100 will develop and grow the roots 121 in a location where the roots 121 are not already restrained by the root growth promoter 30.

[0144] The root growth promoter 30 sags from the root portion 120 and is not supported by any other means. This sagging is caused, at least in part, by contact between the root portion 120 and the root growth promoter 30, i.e., by pressure exerted by the root portion 120 on the root growth promoter 30. Further details of the root growth promoter 30 are discussed below in connection with various embodiments of the root growth promoter 30 shown in Figures 6A-6E.

[0145] In the method steps shown in Figure 1, the plant 100 is allowed to grow under the influence of nutrients and exposure to light entering the greenhouse 200 through the glass roof. During growth, the plant 100 forms a new growth N of the stem 110 above the top T, as best shown in Figure 4. Figure 4 represents the plant 100 before growth and before the state shown in Figure 1.

[0146] After growth of the plant 100, the original apex T becomes the previous apex and the new growth N then becomes the apex, as shown in Figure 4. The growth of the plant 100 further involves the growth of the roots 120 inside the root compartment 20, which in turn involves the growth of the crop 111 and leaves 112.

[0147] After growing the plant 100, the method includes the step of harvesting the crop 111 and leaves 112 from the stem 110, as shown in Figure 2, where the crop 111 and leaves 112 are cut from the bottom B of the stem 110, i.e. the part of the stem 110 located immediately above the root 120 and the root compartment 10. Thus, the remaining bottom B essentially consists of only a portion of the stem 110 and no longer contains any produce or leaves.

[0148] After the plant 100 has grown, the length of the stem 110 is increased. In order to keep the length of the stem 110 substantially constant, the plant 100 is lowered after some growth. The lowering, represented in Figure 3 by the downward arrow L, means that the suspension of the plant 100 relative to the greenhouse roof structure 201 is changed so that the plant 100 hangs down.

[0149] Thus, prior to lowering, the plant 100 was suspended at a height H below the greenhouse roof structure 201, as shown in Figures 1 and 2. After lowering, the plant 100 was suspended at a lower height H' below the greenhouse roof structure 201, as shown in Figures 3 and 4. The plant 100 is therefore lower than a lower height h, which is equal to the lower height H' minus the original height H.

[0150] During descent, the clamps clamping the stem 110 of the plant 100 at the top T are released. After descent, the clamps are clamped again, so that at least one of the clamps is configured to clamp the new growth N of the stem 110, i.e. above the original top T. The plant 100 is now at least partially suspended by the new growth N, which then becomes, by definition, the new top of the stem.

[0151] After the descending step, the bottom B of the stem 110 likewise becomes free to hang down into the root compartment 10. Thus, the root compartment 10 remains substantially stationary and does not descend with the plant 100.

[0152] The lowering step further includes an upward shift of the root growth promoter 30 relative to the plant over a height h substantially equal to the height h to which the plant 100 is lowered. In this way, the bottom B of the stem 110 in the root compartment 10 becomes surrounded by the root growth promoter 30 as well. The root growth promoter 30 is configured to thereby effect the plant 100 to develop and grow roots 121 at a position where the roots 121 are not yet restrained by the root growth promoter 30. Thus, the plant 100 will have extra motivation to grow roots 121 at the bottom B of the stem 110 that has just been lowered into the root compartment 10, since the root growth promoter 30 is away from the stem 110 and thus does not yet impede root growth at the bottom B.

[0153] The original bottom portion B of the stem 110 , which is now disposed in the root compartment 10 , will be exposed to nutrients, oxygen and water sprayed by the spraying device 20 .

[0154] After descent, the base B of the stem 110 and the original root 120 join together to form a new root 120 ′, and a new base B′ of the stem 110 is defined immediately above the root compartment 10 .

[0155] As a result of the upward shift of the root growth promoter 30, the bottom end 122 of the root portion 130 becomes exposed below the root growth promoter 30. This bottom end 122 is no longer useful as new roots 121 form at the bottom B of the stem 110. According to this embodiment of the method, the root portion 120 is pruned at the bottom end 122 after the plant 100 has descended.

[0156] Pruning is performed to prevent the root section 120 from growing too large inside the root compartment 10. After pruning, the length of the new root section 120' is substantially the same as the length of the original root section 120 before it was lowered.

[0157] Pruning involves pruning the bottom end 122 of the root section 120 to a height h substantially equal to the height h to which the plant has been lowered, ie, equal to the original height H minus a lower height H'.

[0158] Finally, these steps are repeated so that the step of Figure 4 is again followed by the step of Figure 1. During the repetition, the plant 100 is grown while being watered with the spraying device 20, followed by lowering and root pruning.

[0159] Figure 5 shows an embodiment of a cultivation assembly 1 according to the invention, which is similar to the cultivation assembly shown in Figures 1 to 4 and illustrates an embodiment of the cultivation method shown in those figures. In comparison to Figures 1 to 4, the cultivation assembly 1 in Figure 5 includes a root portion 120 that hangs freely in the root compartment 10 in the absence of a root growth promoter, thereby clearly showing the roots 121 of the plant 100.

[0160] Figures 6A-6E show various embodiments of root growth promoters 30 according to the present invention, which are suitable for inclusion in the cultivation assembly 1 shown in Figures 1-4 and which illustrate the embodiments of the cultivation method shown in these figures or in the cultivation assembly 1 shown in Figure 5.

[0161] All of the embodiments of the root growth promoter 30 in Figures 6A-6E are configured to surround the root portion 120 of the plant 100 and are configured to be supported under the influence of an outward clamping force acting on the root growth promoter 30 around the periphery of the root portion 120. The root growth promoter 30 is configured to form a lateral constraint for the growth of the root portion 120. The root growth promoter 30 is thereby configured to physically block the lateral growth of the roots 121.

[0162] The root growth promoter 30 is configured to form a fixed reference point at a processing station for the plant 100, for example at an inspection station and / or a harvesting station. At such stations, the plant 100 may be further held by its root growth promoter 30. Each root growth promoter 30 is uniform for each plant 100, allowing for a more secure grip compared to when the root portion 120 itself is gripped.

[0163] The root growth promoter 30 is configured to hang down from the root portion 120, such that it is not supported by any other external means, such as being attached to the root compartment 10. This hanging can occur due to contact between the root portion 120 and the root growth promoter 30, i.e., the pressure of the root portion 120 on the root growth promoter 30.

[0164] The root growth promoter 30 of the present invention may comprise a frusto-conical annular clamping flap 31 at its apical end made of a flexible material such as rubber. The clamping flap 31, shown in Figure 6A, is configured to be under the influence of gravity acting on the root growth promoter 30 and to clamp the bottom B of the stem 110 of the plant 100. As a result of its flexibility and downwardly pointing frusto-conical shape, the clamping flap 31 is configured to allow upward movement of the root growth promoter 30 relative to the stem 110 of the plant 100.

[0165] All of the embodiments of the root growth promoter 30 shown in Figures 6A-6E include a peripheral wall 32 that defines a longitudinal axis E of the through passage 33. When viewed along the longitudinal axis E, all of the embodiments of the root growth promoter 30 shown in Figures 6A-6E include a peripheral wall 32 that has a hollow cross-section having a circular shape.

[0166] The root growth promoter 30 includes a plurality of side openings 34 in the peripheral wall 32 each providing access to a through passage 33 in one or more horizontal directions H perpendicular to the longitudinal axis E, the side openings 34 in the peripheral wall 32 being configured to allow the passage of water and nutrients to the roots 121 of the root portion 120 restricted to the through passage 33.

[0167] The embodiments of root growth promoter 30 in Figures 6A-6E differ in the size and shape of the side openings 34. In the embodiment of Figure 6A, the side openings 34 have a circular shape and are arranged relative to one another along a spiral line 35 around the circumference of peripheral wall 32, as best seen in the enlarged detail view in Figure 6A.

[0168] The root growth promoter 30 in FIG. 6B extends substantially parallel to the longitudinal axis E, i.e., in a vertical direction V, and has relatively narrow rectangular side openings 36, e.g., rectangular slits, in a horizontal direction H perpendicular to the vertical direction V, the rectangular side openings 36 being arranged in a linear horizontal row extending around the circumference of the peripheral wall 32 in the horizontal direction H.

[0169] The root growth promoter 30 of Figure 6C also has rectangular side openings 37, but these are wider in the horizontal direction H compared to the side openings 36 of Figure 6B. Additionally, the side openings 37 of the root growth promoter 30 of Figure 6C have rounded upper and lower edges which may be beneficial in cutting off roots 121 that may protrude through the side openings 37 as the root growth promoter 30 is moved upward.

[0170] In the embodiment of the root growth promoter 30 of Figure 6D, side openings 38 having a triangular shape are provided. And the triangular shaped side openings 37 are arranged in linear rows parallel to the horizontal direction H around the perimeter of the peripheral wall 32.

[0171] In the embodiment of the root growth promoter 30 of Figure 6E, the peripheral wall 32 includes circular side openings 34. In contrast to the circular side openings 34 of Figure 6A, the circular side openings 34 in the embodiment of Figure 6E are arranged in straight horizontal rows around the circumference of the peripheral wall 32, parallel to the horizontal direction H.

[0172] 7A-7C show schematic diagrams of an embodiment of a part of an indoor farm according to the present invention. The indoor farm is embodied as a greenhouse 200 including a greenhouse roof structure 201. The greenhouse 200 is configured to grow plants 100, such as tomatoes in this embodiment, and includes a number of growing assemblies 1 as shown in FIG.

[0173] The roof structure 201 of the greenhouse 200 is configured to fully support the plants 100 such that the plants 100 hang freely from the roof structure 201. The greenhouse 200 includes a central support wire 203 that extends substantially perpendicular to the roof structure 201. Each of the growing assemblies 1 includes a wire, e.g., a metal wire 202, attached to the central support wire 203, each configured to support a respective plant 100.

[0174] The cultivation assemblies 1 are arranged next to each other such that the plants 100 are arranged in a row R below a central support wire 203. The cultivation assemblies 1 share a single root compartment, which is embodied as an enclosed root trough 10'. The root trough 10' extends substantially parallel to the central support wire 203 such that all the plants 100 in the plant row R have their respective roots 120 located in the root growth promoter 30 of the root trough 10'.

[0175] The root trough 10' is substantially enclosed and includes a slit 11' at its top. The slit 11' receives the plants 100 such that the roots 120 of all the plants 100 in the row R enter the root trough 10'. The root trough 10' thus includes a plurality of spray devices 20 spread over the length of the root trough 10'.

[0176] The central support wire 203 is configured to permit movement of the metal wires 202 and thus movement of the plants 100, allowing the plants 100 to slide along the row R. The roots 120 of the plants 100 thereby move through the root trough 10' so that even during movement of the plants 100 the roots 120 remain enclosed in the root trough 10' and can remain sprayed by the spraying device 20 whilst being moved through the slits 11'.

[0177] The greenhouse 200 further comprises a winch 204 associated with the central support wire 203. The winch 204 is configured to transport the movable plants 100' through the greenhouse 200 and move the plants 100 from the growing location, i.e., the root trough 10', towards one or more processing stations, which may be one or more of a drop station, a root pruning station, an inspection station and / or a harvesting station.

[0178] The embodiments of Figures 7A and 7B differ from each other in that the plants 100 in the embodiment of Figure 7A each have a root growth promoter 30 around their roots, and a dedicated spraying device 20 is provided for each of the plants 100. In the embodiment of Figure 7B, instead, the roots of the plants 100 are not provided with a root growth promoter, but are freely exposed in the root gutter 10'.

[0179] Furthermore, fewer spray devices 20' are provided in the embodiment of Fig. 7B compared to Fig. 7A. However, each spray device 20' can spray over a wider spray area, so that each spray device 20' can provide water and nutrients to multiple different plants 100 instead of just one.

[0180] In the embodiment of Figure 7C, the plant 100 is provided with a root growth promoter 30, similar to that of Figure 7A. However, the embodiment of Figure 7C includes a broad area spray device 20' present in the embodiment of Figure 7B instead of the individual spray devices. Thus, the position of the spray device 20' is not coordinated with the position of the plant 100.

[0181] As an alternative to the central support wire 203 and winch 204, the roof structure may, for example, comprise rails extending at least between the growing location and the processing station. A movable support structure may then be provided, comprising one or more wheels or rollers, supported by the rails and configured to roll on the rails.

[0182] 8A and 8B show diagrammatically an embodiment of a greenhouse 200 according to the invention. The greenhouse 200 comprises a growing area C in which are located a number of rows R of plants 100. Each of the plants 100 has its roots arranged in a respective root compartment 10.

[0183] The greenhouse 200 comprises a roof structure 201 on which a number of chains 205 are attached, for example in chain loops 205', that extend through the greenhouse 200. At the growing location C, each row R of plants 100 includes its own chain 205 that extends across the root compartment 10. Each of the plants 100 is suspended from a hook system attached to the chains 205, and the plants 100 are moved through the greenhouse 200 by cycling the chains 205.

[0184] The greenhouse 200 further comprises a centralized treatment location P, which is separated from the cultivation location C by a greenhouse wall 206. A chain loop 205' extends from the cultivation location C to the treatment location P and defines a transport path for the moving plants 100'. The transport path is represented by an arrow in FIG. 8.

[0185] The chain loop 205' is provided at a treatment location P and passes along a number of treatment locations located away from the cultivation location C, and upon passing the treatment location C, the moving plant 100' can receive a certain amount of treatment at the treatment location P which in the prior art was performed at the cultivation location.

[0186] After entering the processing location P, each plant 100' first moves along an inspection station 210 as it moves along the transport path. The inspection station 210 is configured to inspect one or more parameters of the plant 100', i.e. by optical inspection. This inspection is performed autonomously by a number of cameras in order to gain knowledge about the physical state of the plant 100'. Typically, the inspected parameters may be, but are not limited to, the length of the plant 100', the size and / or number of leaves 112, and / or the presence and / or ripeness of the crop 111.

[0187] The plant 100' then passes along a harvesting station 220 on its transport path. The harvesting station 220 is configured to harvest the crop 111 from the plant 100', and in particular harvest the crop 111 that is detected at the inspection station 210 to be sufficiently ripe.

[0188] After the harvesting station 220, the plant 100' passes along a defoliation station 230 that is configured to remove the lowest leaves 112 from the plant 100', i.e., to harvest the leaves 112 at the point along the stem of the plant where the crop 111 was harvested.

[0189] Finally, before returning to the cultivation location C, the plant 100′ passes along a human worker station 240. At the human worker station 240, the plant 100′ may be lowered by a human worker 241 to allow the plant to grow further. Additionally, the human worker 241 at the human worker station 240 may be configured to prune a bottom end of the root portion of the plant 100′ before the plant 100′ returns along the transport path to the cultivation location C. Additionally, the human worker 241 at the human worker station 240 may remove leaves 112 that were erroneously or not removed at the harvesting station 220 to produce 11 from the plant 100.

[0190] The embodiments of Figures 8A and 8B differ in that the plants 100 in the embodiment of Figure 8A are each arranged in their own root compartment 10, which is embodied as an individual vertical tube for each of the plants. In the embodiment of Figure 8B, the root compartment is embodied as an enclosed root trough 10' with a slit 11' at the top, so that the plants 100 can move along the length of the slit 11' and adjust the spacing between adjacent plants 100.

Claims

1. A method for cultivating a plant (100, 100'), comprising: suspending a plant including a stem (110) and a root part (120), including freely suspending the plant by the top of the stem, wherein when there is no growth medium, the root part hangs freely from the stem in a substantially enclosed root compartment (10, 10'), the root compartment is provided with a substantially enclosed trough, and is configured to receive the root parts of a plurality of plants arranged in rows (R) extending parallel to the trough, the trough includes a slit (11') at its top, the width of the slit is narrower than the width of the trough, i.e., the width perpendicular to the elongated direction of the trough, and the plant enters the trough through the slit; the step of suspending the plant; supplying water to the root part in the root compartment; the step of supplying water to the plant; lowering the plant after growing the plant, such that the bottom (B) of the stem hangs freely into the root compartment, and growing new roots at the bottom of the stem in the root compartment; after the step of lowering the plant, the step of suspending the plant again by a newly grown part (N) of the stem; the step of lowering the plant; pruning at least a part of the root part at the bottom end; repeating the step of lowering the plant and the step of pruning the root each time the plant is grown; A method comprising the above steps.

2. The step of suspending the plant further includes clamping the top of the stem with at least one clamp of a support structure. The method according to Claim 1.

3. The step of supplying water includes spraying the water onto the root part in the root compartment. The method according to Claim 1 or 2.

4. The method according to any one of Claims 1 to 3, wherein the root compartment is substantially opaque, particularly substantially opaque to visible light and ultraviolet spectral light.

5. The root part is at least partially densely surrounded by an outer peripheral root growth promoter. The method according to any one of Claims 1 to 4, wherein the root growth promoter is preferably exclusively supported under the influence of an outward clamping force around the root part acting on the root growth promoter. **Claim 6**: The method according to claim 4 or 5, wherein the lowering step further comprises a upward shift of the root growth promoter with respect to the plant over a height substantially equal to the height to which the plant has been lowered, such that the bottom of the stem in the root compartment is at least partially surrounded by the root growth promoter. **Claim 7**: The method according to any one of claims 1 to 6, further comprising a step of inspecting, for example, optically, one or more parameters of the plant. **Claim 8**: The lowering step, the step of pruning the roots, the step of inspecting and / or harvesting are performed at each of one or more stations located away from the cultivation site (C), prior to the lowering step, the step of pruning the roots, the step of inspecting and / or harvesting, a step of moving the plant from the cultivation site to the station, after the lowering step, the step of pruning the roots, the step of inspecting and / or harvesting, a step of moving the plant from the station back to the cultivation site, The method according to any one of claims 1 to 7, further comprising. **Claim 9**: The method according to claim 8, wherein the plant is suspended from a movable support structure. **Claim 10**: A support structure configured to suspend the stem of the plant, a substantially enclosed root compartment configured to receive the root portion of the plant, a water supply device (20) at least partially disposed in the root compartment and configured to supply the water to the root portion, comprising: the root compartment comprises a substantially enclosed trough, configured to receive the root portions of a plurality of plants arranged in a row (R) extending parallel to the trough, the trough includes a slit (11') at its top, the width of the slit is narrow compared to the width of the trough, i.e., the width perpendicular to the elongated direction of the trough, and the plant enters the trough through the slit. A cultivation assembly (1) for performing the method according to any one of claims 1 to 9. **Claim 11**: Further comprising a lowering station configured to lower the plants relative to the support structure, a root pruning station configured to cut off a part of the root, an inspection station for examining one or more parameters of the plant and / or a harvesting station configured to harvest crops from the plant, wherein the lowering station, the root pruning station, the inspection station and / or the harvesting station are preferably arranged at a location remote from the cultivation location, wherein the support structure is configured to move the plant between the cultivation location and one or more stations. The cultivation assembly according to claim 10. **Claim 12**: An outer peripheral root growth promoter for the cultivation assembly according to claim 10 or 11, wherein the root growth promoter is preferably configured to at least partially and tightly surround the root and be exclusively supported under the influence of an outward clamping force in the circumferential direction of the root acting on the root growth promoter. **Claim 13**: Defining a through-passage along the long axis, having one or more side openings, and having a peripheral wall providing access to the through-passage in one or more transverse directions perpendicular to the long axis, and / or the peripheral wall of the root growth promoter extends over a length substantially equal to the length of the root, i.e., along the long axis in the vertical direction. The outer peripheral root growth promoter according to claim 12. **Claim 14**: A greenhouse (200) for cultivating plants, comprising the cultivation assembly according to claim 10 or 11, wherein the support structure is attached to the roof structure of the greenhouse. **Claim 15** wherein the roof structure comprises the movable support structure extending, for example, at least between the cultivation location and one or more of the lowering station, the root pruning station, the inspection station and / or the harvesting station. The greenhouse (200) according to claim 14.

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