WO2023023542A1

WO2023023542A1 - Method for improving yield and height of short-cycle leafy greens using far-red light

Info

Publication number: WO2023023542A1
Application number: PCT/US2022/075058
Authority: WO
Inventors: Renner ILSE
Original assignee: Upward Enterprises Inc.
Priority date: 2021-08-17
Filing date: 2022-08-17
Publication date: 2023-02-23

Abstract

A method for enhancing yield of short-cycle plants includes producing a broad- spectrum white light with a plurality of white light sources, the broad-spectrum white light having a wavelength range of 350 nm to 800 nm and a FAR-PAR ratio of about 3%; producing FAR light with a plurality of FAR light sources; and exposing the plants to a combined light for a predetermined time period each day for a predetermined number of days, the combined light comprising the broad-spectrum white light and the FAR light, the combined light having a photosynthetic photon flux density of about 200 and a FAR-PAR ratio of about 5% to about 30%.

Description

METHOD FOR IMPROVING YIELD AND HEIGHT OF SHORT-CYCLE LEAFY GREENS USING FAR-RED LIGHT

Cross-Reference to Related Applications

[0001] This application claims priority to U.S. Provisional Application No. 63/234,078, filed on August 17, 2021 , titled "Enhanced height and yield of short-cycle leafy greens grown using fixed-spectrum LED fixture," which is hereby incorporated by reference.

Technical Field

[0002] This application relates generally to methods for growing agricultural products.

Background

[0003] Indoor vertical farms use light emitting diodes (LEDs) to supply energy for photosynthesis and information to growing plants that impacts phenotype (e.g., size, height, shape, color, smell, molecular properties, etc.). A phenotypic trait desired in most vertical farms is compactness in order to grow more plants within a given area. However, under certain conditions, and with certain crop types, spectra that promote taller plants with larger leaves are beneficial. Microgreens and baby greens lack a formal definition but are considered immature plants harvested early in development with microgreens being even younger than baby greens. Phenotypes that are less compact and have greater leaf expansion result in greater biomass accumulation of the aerial tissue resulting in greater potential yields. It has been challenging with prior methods to harvest young tender green edible plants of the type described herein, in part because an automated or mechanized harvester could not easily access enough space below the plants and so the plants had to remain in the ground longer or a portion of the plants intended for commercial use could be lost if this portion was damaged as a result of the harvesting process.

Summary

[0004] Example embodiments described herein have innovative features, no single one of which is indispensable or solely responsible for their desirable attributes. The following description and drawings set forth certain illustrative implementations of the disclosure in detail, which are indicative of several exemplary ways in which the various principles of the disclosure may be carried out. The illustrative examples, however, are not exhaustive of the many possible embodiments of the disclosure. Without limiting the scope of the claims, some of the advantageous features will now be summarized. Other objects, advantages and novel features of the disclosure will be set forth in the following detailed description of the disclosure when considered in conjunction with the drawings, which are intended to illustrate, not limit, the invention.

[0005] An aspect of the invention is directed to a method for enhancing a yield of short-cycle plants, comprising: providing a broad-spectrum white light with a plurality of white light sources, the broad-spectrum white light having a wavelength range that is greater than or equal to 350 nm and less than or equal to 800 nm and a FAR-PAR ratio of about 3%, wherein FAR is far-red light having a wavelength range that is greater than or equal to 700 nm and less than or equal to 750 nm, and PAR is photosynthetically active radiation having a wavelength range that is greater than or equal to 400 nm and less than or equal to 700 nm; producing FAR light with a plurality of FAR light sources; and exposing the plants to a combined light for a predetermined time period each day for a predetermined number of days, the combined light comprising the broad-spectrum white light and the FAR light, the combined light having a photosynthetic photon flux density of about 200 and a FAR-PAR ratio of about 5% to about 30%.

[0006] In one or more embodiments, the white light sources and the FAR light sources are mounted on a common light fixture. In one or more embodiments, the white light sources comprise white light-emitting diodes (LEDs) and the FAR light sources comprise FAR LEDs. In one or more embodiments, the white LEDs and the FAR LEDs are fixed-spectrum LEDs.

[0007] In one or more embodiments, the method further comprises harvesting the plants with a mechanical harvester. In one or more embodiments, the predetermined time period is about 8 hours to about 24 hours, and the predetermined number of days is about 6 days to about 12 days. In one or more embodiments, the method further comprises placing the plants in a chamber having a controlled light environment.

[0008] In one or more embodiments, the plants comprise Brassica plants and/or Brassicaceae plants. In one or more embodiments, the method further comprises placing the plants in a chamber having a controlled light environment.

[0009] Another aspect of the invention is directed to a method for enhancing a yield of short-cycle plants, comprising: producing a light with a plurality of variable- frequency light sources, the light having a photosynthetic photon flux density of about 200 and a FAR-PAR ratio of about 5% to about 30%, wherein FAR is far-red light having a wavelength range that is greater than or equal to 700 nm and less than or equal to 750 nm, and PAR is photosynthetically active radiation having a wavelength range of that is greater than or equal to 400 nm and less than or equal to 700 nm; and exposing the plants to the light for a predetermined time period each day for a predetermined number of days.

[0010] In one or more embodiments, the variable-frequency light sources comprise variable-frequency light-emitting diodes. In one or more embodiments, the method further comprises harvesting the plants with a mechanical harvester. In one or more embodiments, the method further comprises placing the plants in a chamber having a controlled light environment.

Brief Description of the Drawings

[0011] For a fuller understanding of the nature and advantages of the concepts disclosed herein, reference is made to the detailed description of preferred embodiments and the accompanying drawings.

[0012] Fig. 1 is a side view of an indoor growing system according to an embodiment.

[0013] Fig. 2 is an example spectrum of a broad-spectrum white light.

[0014] Fig. 3 is an example spectrum of a narrowband far-red light.

[0015] Fig. 4 is an example of a combined spectrum having a FAR-PAR ratio of about 5% to about 30%. [0016] Fig. 5 is a bottom view of the light fixture illustrated in Fig. 1 according to an embodiment.

[0017] Fig. 6 is a bottom view of the light fixture illustrated in Fig. 1 according to another embodiment.

[0018] Fig. 7 is a bottom view of the light fixture illustrated in Fig. 1 according to another embodiment.

[0019] Fig. 8 is a side view of an indoor growing system according to another embodiment.

[0020] Fig. 9 is a side view of an indoor growing system according to another embodiment.

[0021] Fig. 10 is a block diagram of the controller illustrated in Fig. 8 according to an embodiment.

[0022] Figs. 11 , 12, 13, and 14 are graphs of experimental results for the cultivars kohlrabi, kale, radish, and broccoli, respectively.

[0023] Figs. 15A-D are side views of simplified illustrations of microgreen stages 1 -4, respectively, according to an embodiment.

[0024] Fig. 16 is a flow chart of a method for improving the yield of short-cycle plants according to an embodiment.

[0025] Fig. 17 is a flow chart of a method for improving the yield of short-cycle plants according to another embodiment. Detailed Description

[0026] The production of short-cycle leafy greens such as microgreens or baby greens harvested by a mechanical harvester for all aerial biomass (plant material above the growing medium) benefit from having a less compact and taller stature as this allows for a cleaner harvest and thus greater realized yields. In some aspects, the present invention employs a combination of broadband white light and far-red light (e.g., in or within the 700 to 750 nm wavelength range) to affect the growth cycle of brassica microgreens and similar agricultural vegetation. The present inventors have found this to enhance the growth of the stemmata of said plants so as to beneficially extend the plants upwards and elongate the stemmata to better allow for automated and/or mechanical harvesting (cutting) of the plants at or near said stemmata. An aspect of the present invention yields harvestable plants where the leaves can be desirably tender and young but where the stems of the plants are artificially elongated for the foregoing purpose (sometime referred to as "leggy" plants). This method stands in contrast to conventional thinking regarding leafy green produce growing where emphasis was conventionally placed on developing the edible leafy portions and little interest was taken in encouraging growth of the generally non-edible stems.

[0027] Fig. 1 is a side view of an indoor growing system 10 according to an embodiment. The system 10 includes a container 100 that holds a growing medium 1 10 for growing agricultural plants 115. The growing medium 1 10 can comprise or consist of soil. Alternatively, the growing medium 1 10 can comprise or consist of a soilless growing medium. For example, the container 100 and growing medium 1 10 can form a hydroponic or an aquaponic system. In a hydroponic system, the growing medium 1 10 can include coconut husk and/or grow rocks. In an aquaponic system, the growing medium 110 can include clay pellets.

[0028] A plurality of grow lights 120 are located above the container 100 and mounted on a light fixture 130. A power source 140 is electrically coupled to the grow lights 120. The power source 140 can provide AC electric power or DC electric power to the grow lights 120. The container 100, the grow lights 120, the light fixture, and optionally the power source are located in a chamber 150 having a controlled-light environment, such as a shipping container. A controller 141 such as a microcontroller, processor, application specific integrated circuit or similar device configured and arranged to execute program instructions and to exchange data with a network over a network connection 142 may optionally be used in some embodiments to modulate or control power to the power source 140 and thus to programmably affect the delivery, timing, duty cycle, time-varying power and/or time-varying fraction of the constituent wavelengths of light delivered to the growing plants. In some examples, the delivery of light and the intensity and mixture of wavelengths in the delivered light may be varied over the course of a day and may correspond to the natural day/night (light/dark) cycle of the environment.

[0029] The grow lights 120 are preferably LEDs but can be or include other grow lights. For example, the grow lights 120 can comprise or consist of high-pressure sodium (HPS) grow lights, high intensity discharge (HID) grow lights, metal halide (MH) grow lights, and/or other grow lights. The grow lights 120 are configured to produce a customized or tailored spectra that includes photosynthetically active radiation (PAR) and far-red (FAR) light. In general, PAR includes or consists of the spectral range of 400 nm to 700 nm. For example, PAR can be greater than or equal to 400 nm and less than or equal to 700 nm. In another example, PAR can be 400 nm to 600 nm, 500 nm to 700 nm, 400 nm to 500 nm, or another value or range between any two of the foregoing wavelengths. The FAR spectrum includes or consists of the spectral range of 700 nm to 750 nm. For example, the FAR spectrum can be greater than or equal to 700 nm and less than or equal to 750 nm, including 710 nm, 720 nm, 730 nm, 740 nm, or any value or range between any two of the foregoing wavelengths. In an optional embodiment, the FAR spectrum can include or consist of the spectral range of 700 nm to 800 nm, for example greater than or equal to 700 nm and less than or equal to 800 nm. For example, the FAR spectrum can be greater than or equal to 700 nm and less than or equal to 750 nm, including 710 nm, 720 nm, 730 nm, 740 nm, 750 nm, 760 nm, 770 nm, 780 nm, 790 nm, or any value or range between any two of the foregoing wavelengths.

[0030] The customized spectra can have a FAR-PAR ratio of about 5% to about 30%, including about 7%, about 10%, about 15%, about 20%, about 25%, or any value or range between any two of the foregoing values. As used herein, "about" means plus or minus 10% of the relevant value. The FAR-PAR ratio indicates the amount of FAR light in a spectrum compared to PAR light. For example, the FAR-PAR ratio is determined by dividing the number the photons emitted per unit time in the FAR spectrum (e.g., greater than or equal to 700 nm and less than or equal to 750 nm) divided by the number the photons emitted per unit time in the PAR spectrum (greater than or equal to 400 nm and less than or equal to 700 nm). Thus, the FAR-PAR ratio is equal to ^{pflotonS700nm}-^750nm There are several ways to quantify the amount of FAR light Photons_400nm-700nm in a spectrum, but for the purposes of this disclosure the FAR-PAR ratio will be used. [0031] The grow lights 120 can have various configurations to produce a FAR- FAR ratio of about 5% to about 30%. In one example, the grow lights 120 are fixed spectrum and include white lights 122 and FAR lights 124. The white lights 122 can be or include broad-spectrum white lights, such as broad-spectrum white LEDs. An example spectrum 20 of a broad-spectrum white light is illustrated in Fig. 2. The example spectrum 20 includes a primary peak of relative intensity between 400 nm and 500 nm (e.g., at 450 nm) and a secondary peak of relative intensity between 600 nm and 700 nm (e.g., at 675 nm). The relative intensity generally decreases from the primary peak to the secondary peak and then decreases further after the secondary peak. The relative intensity of the wavelengths above 700 nm is low. The wavelengths of the broad-spectrum white light can range from 350 nm to 800 nm, For example, the wavelengths of the broad-spectrum white light can be greater than or equal to 350 nm and less than or equal to 800 nm, including 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, or any value or range between any two of the foregoing wavelengths.

[0032] The FAR lights 124 can be or include FAR LEDs or another type of grow light 120. An example spectrum 30 of a FAR light 124 is illustrated in Fig. 3. The example spectrum 30 includes a peak of relative intensity between 700 nm and 800 nm (e.g., at 750 nm). In one example, the peak is at 730 nm and the relative intensity can be high from 720 nm to 740 nm. In another example, the peak is at 730 nm and the relative intensity can be high from 700 nm to 800 nm. The relative intensity is low or zero below 650 nm (e.g., between 400 nm and 650 nm) and above 800 nm. The relative intensity begins to increase around 650 nm and increases sharply at 700 nm. The wavelengths of the FAR light 124 can range from 650 nm to 800 nm. For example, the wavelengths of the FAR light 124 can be greater than or equal to 650 nm and less than or equal to 800 nm, including 675 nm, 700 nm, 725 nm, 750 nm, 775 nm, or any value or range between any two of the foregoing wavelengths.

[0033] The white lights 122 and FAR lights 124 are configured to produce a combined or net spectrum have a FAR-PAR ratio of about 5% to about 30%. An example combined spectrum 40 having a FAR-PAR ratio of about 5% to about 30% is illustrated in Fig. 4. The example combined spectrum 40 includes a first peak of relative intensity between 400 nm and 500 nm (e.g., at 450 nm) and a second peak of relative intensity between 600 nm and 700 nm (e.g., at 675 nm). The relative intensity of the first peak can be greater than or about equal to the relative intensity of the second peak. The relative intensity generally decreases from the primary peak to the second peak and then decreases further after the second peak. The relative intensity of the wavelengths below 400 nm and above 800 nm is low or zero. The relative intensity is elevated but below the first and second peaks between 500 nm and 700 nm.

[0034] In an alternative embodiment, the grow lights 120 can be variablespectrum and can be controlled to produce a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40.

[0035] The system 10 can grow a variety of plants 115 such as microgreens, Brassica and/or Brassicaceae plants (e.g., turnips, kohlrabi, cabbage, collard greens, kale, cauliflower, broccoli, Brussels sprouts, radish, and/or cabbage). Plants 115 grown under grow lights 120 that produce a FAR-PAR ratio of about 5% to about 30% have an increase in plant height (e.g., hypocotyl extension), leaf area, and biomass compared to the same plants grown only under broad-spectrum white lights (e.g., spectrum 20) over the same time period. The time period of interest is generally a short cycle to produce microgreens. An example time period is about 6 days to about 12 days after seeding. A FAR-PAR ratio of greater than about 30% (e.g., about 30% to about 40%) can be used, but may not be as effective as a FAR-PAR ratio of about 5% to about 30%. The benefits of an increase in plant height (e.g., longer stems) is to allow the plants 115 to be automatically harvested (e.g., with a mechanical or electromechanical harvester). Increases in leaf area and biomass improve the yield of the plants 115.

[0036] Fig. 5 is a bottom view of the light fixture 130 according to an embodiment. In this embodiment, the light fixture 130 includes an array of grow lights 120. The white lights 122 and FAR lights 124 are arranged in a repeating pattern such that the FAR lights 124 are uniformly distributed (or substantially uniformly distributed) throughout the array so to provide a uniform (or a substantially uniform) spectrum to the plants 115 (Fig. 1). The spectrum produced the grow lights 120 has a FAR-PAR ratio of about 5% to about 30% and can appear the same as or similar to the example combined spectrum 40.

[0037] Fig. 6 is a bottom view of the light fixture 130 according to another embodiment. In this embodiment, the pattern of the white lights 122 and FAR lights 124 is offset in row 602 compared to rows 601 and 603, which can improve the uniformity of the spectrum produced by the grow lights 120.

[0038] Fig. 7 is a bottom view of the light fixture 130 according to another embodiment. In this embodiment, the white lights 122 and FAR lights 124 are arranged randomly or pseudo-randomly in the array, which can improve the uniformity of the spectrum produced by the grow lights 120.

[0039] Fig. 8 is a side view of an indoor growing system 80 according to another embodiment. System 80 is the same as system 10 except that system 80 includes a controller 800. The controller 800 can be that is electrically coupled to and/or in electrical communication with the grow lights 120. In one example, the grow lights 120 have a variable or controllable spectrum and the controller 800 is configured to send control signals to the grow lights 120 to produce a spectrum having a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40. The controller 800 can cause some of the grow lights 120 to function as white lights 122 and some of the grow lights 120 to function as FAR lights 124, for example as described above. Alternatively, the controller 800 can cause some or all of the grow lights 120 to produce a spectrum having a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40.

[0040] In another embodiment, the controller 800 can be configured to send a first control signal to the grow lights 120 that causes cause some or all of the grow lights 120 to operate in a first state and to send a second control signal that causes cause some or all of the grow lights 120 to operate in a second state. In one example, some or all of the grow lights 120 are variable or controllable spectrum lights that function as white lights 122 in the first state and as FAR lights 124 in the second state. For example, some or all of the grow lights 120 can function as white lights 122 (e.g., in the first state) for a first time period and as FAR lights 124 (e.g., in the second state) for a second time period. The length/duration of the first and second time periods can be selected such that the cumulative or net output of the grow lights 120 has a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40.

[0041] In another embodiment, the controller 800 can be configured to send a first control signal to the power source 140 that can cause the power source 140 to provide power to the white lights 122 (e.g., when the grow lights 120 are fixed- spectrum) for a first time period and to provide power to the FAR lights 124 for a second time period. The length/duration of the first and second time periods can be selected such that the cumulative or net output of the grow lights 120 is equivalent to a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40.

[0042] In another embodiment, the controller 800 can cause the power source 140 to vary the output power of the white lights 122 and the FAR lights 124 (e.g., when the grow lights 120 are fixed-spectrum). The output power of the white lights 122 can be the same as or different than the output power of the FAR lights 124. The output power of the white lights 122 and the FAR lights 124 can be selected such that the cumulative or net output of the grow lights 120 has a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40.

[0043] In some embodiments, the controller 800 is electrically coupled to an array of switches 910, as illustrated in Fig. 9. The switches 910 can be internal to the power source 140, internal to the light fixture 130, or external to the power source 140 and light fixture 130. The switches 910 can include solid-state switches and/or contact switches. In the closed state, a respective switch 910 electrically couples the power source 140 to one or more grow lights 120. In the open state, the respective switch 910 electrically decouples the power source 140 from the grow light(s) 120. The controller 800 can send control signals to the array of switches 910 to cause each switch 910 (or each group of switches) to be in the opened or closed state.

[0044] In one example, the control signals can cause the power source 140 to provide power to the white lights 122 (e.g., when the grow lights 120 are fixed- spectrum) for a first time period and to provide power to the FAR lights 124 for a second time period. The length/duration of the first and second time periods can be selected such that the cumulative or net output of the grow lights 120 is equivalent to a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40.

[0045] In another example, the control signals cause some or all of the switches 910 to transition between the open and closed states to have a duty cycle. For example, the control signals can cause the switches 910 for the white lights 122 to be in the closed state for a predetermined time period while the switches 910 for the FAR lights 124 are opened and shut in a repeatable (e.g., duty cycle) or random pattern such that the net time in which the switches 910 for the FAR lights 124 are in the closed state causes the grow lights 120 to produce a spectrum having a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40. In another example, the control signals can cause the switches 910 for the FAR lights 124 to be in the closed state for a predetermined time period while the switches 910 for the white lights 122 are opened and shut in a repeatable (e.g., duty cycle) or random pattern such that the net time in which the switches 910 for the white lights 122 are in the closed state causes the grow lights 120 to produce a spectrum having a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40. In another example, the control signals can cause the switches 910 for the white lights 122 to have a first duty cycle and the switches 910 for the FAR lights 124 to have a second duty cycle such that the grow lights 120 produce a spectrum having a FAR-PAR ratio of about 5% to about 30%, such as the example combined spectrum 40.

[0046] Fig. 10 is a block diagram of the controller 800 according to an embodiment. The controller 800 includes one or more microprocessors 1010 (e.g., hardware-based microprocessors) and one or more articles of manufacture that comprise non-transitory computer-readable storage media (e.g., computer memory 1020 and one or more non-volatile storage media 1030). The microprocessor(s) 1010 may control writing data to and reading data from the memory 1020 and the nonvolatile storage device 1030 in any suitable manner. The non-transitory computer- readable storage media may store one or more programs, software, instructions, data, and/or other information for operation of the controller 800. In at least some embodiments, the one or more programs include one or more instructions to be executed by the microprocessor 1010 to provide one or more portions of one or more tasks and/or one or more portions of one or more methods disclosed herein. In some embodiments, the non-transitory computer-readable storage media includes data for one or more portions of one or more tasks and/or one or more portions of one or more methods disclosed herein. To perform any of the functionality described herein, the microprocessor 1010 may execute one or more processor-executable instructions stored in one or more non-transitory computer-readable storage media (e.g., in the memory 1020 and/or non-volatile storage device 1030), which may serve as non- transitory computer-readable storage media storing processor-executable instructions for execution by the microprocessor 1010.

[0047] In at least some embodiments, the controller 800 may have one or more communication devices 1040, which may be used to interconnect the controller 800 to one or more other devices and/or systems, such as, for example, one or more networks in any suitable form, including a local area network or a wide area network, such as an enterprise network, an intelligent network, and/or the Internet. Such networks may be based on any suitable technology and may operate according to any suitable protocol and may include wireless networks or wired networks. [0048] Also, in at least some embodiments, the controller 800 may have or be in electrical communication with one or more input devices 1050 and/or one or more output devices 1060. These devices can be used, among other things, to present a user interface. Examples of output devices 1060 that may be used to provide a user interface include printers or display screens for visual presentation of output and speakers or other sound generating devices for audible presentation of output. Examples of input devices 1050 that may be used for a user interface include keyboards, and pointing devices, such as a computer mouse, touch pad, or digitizing tablet. As another example, the controller 800 may receive input information through speech recognition or in other audible formats.

[0049] An embodiment is directed to a system for enhancing a yield of shortcycle plants under artificial light, comprising a plurality of light emitting diodes (LEDs) providing said artificial light, including a plurality of broad-spectrum white light LEDs delivering a first light output covering a wavelength range between 350 nm and 800 nm, and having a FAR-PAR ratio of about 3% from said white light LEDs where said PAR comprises photosynthetically active radiation having a wavelength range between 400 nm and 700 nm. The system also includes a plurality of far-red LEDs delivering a second light output covering a FAR wavelength range between 700 nm and 750 nm.

[0050] In addition, the system comprises a processor-based controller, configured and arranged to receive input signals, execute programmed machine readable instructions and to provide output control signals, said controller programmably outputting one or more control signals to control said broad-spectrum white LEDs and said far-red LEDs. [0051] In an embodiment, said one or more control signals determine a first intensity of said first light output and a second intensity of said second light output, and wherein said one or more control signals modulate said first and second intensities so as to achieve a FAR-PAR ratio of at least 5% from both said plurality of while light LEDs and said plurality of far-red LEDs. The overall combined light from the white LEDs and the far-red LEDs may have a FAR-PAR ration ranging from 5% as stated up to about 30% in some examples. Thus the inclusion and modulation of the relative intensities including said far-red light (second) intensity is used to increase the FAR-PAR ratio and affect the desired grown and enhanced yield.

[0052] An exemplary experiment by the inventors determined the effect of FAR light on the growth of short-cycle leafy green plants. All plants were grown in the same pond, which shares the same irrigation water. Additionally, to help control for changes down the length of a pond, the pond is zoned into four zones, the first zone is a control (broad-spectrum white light only), the second zone is an experimental FAR light treatment, the third zone is another control, and the fourth zone is another experimental FAR light treatment. The experimental FAR light treatment zones were grown with a FAR-PAR value of about 8% to about 9%. Though leaf size was not measured, we did measure cotyledon size but leaf size is different. Cotyledon size did not seem to be affected by FAR light exposure but rather, leaf size likely would be (i.e., tested so far only on microgreens which do not have expanded true leaves typically). All plants were subjected to the same cycle length (within a cultivar) and the same conditions expert for the added FAR light in the experimental FAR augmented conditions. [0053] Exemplary trials included some conditions where all treatments were set to 200 PPFD (photosynthetic photon flux density), which is the typical light intensity used in microgreen production, followed by trials on 100 PPFD versus 200 PPFD with and without added FAR light. In the cases where the inventors performed two different PPFDs of intensity there were four unique treatments (i.e. 200 PPFD + FAR light, 200 PPFD + no FAR light, 100 PPFD + FAR light, 100 PPFD + no FAR light).

[0054] Under 200 PPFD, on broccoli plants, the per-raft yield increase was 16% in one trial and 87% in a second trial when FAR light was added. Both results were statistically significant. The greater increase was seen when plants were harvested at a shorter canopy height. This may have caused the increase to be greater than would be seen if the plants were harvested a day or two later. Under 100 PPFD, the per-raft yield increase was 25%.

[0055] On radish plants, under 200 PPFD, the per-raft yield increase was 3.8% in one trial and 5% in a second trial when FAR light was added. Under 100 PPFD, the per- raft yield increase was 2.5%. The yield increases under 200 PPFD and 100 PFD were not statistically significant.

[0056] On kohlrabi plants, under 200 PPFD, the per-raft yield increase was 15% in one trial and 23% in a second trial when FAR light was added. The yield increases in each trial was statistically significant. Under 100 PPFD, the per-raft yield increase was 2.1 % but was not statistically significant.

[0057] On kale plants, under 200 PPFD, the per-raft yield increase was 8% when FAR light was added, which was statistically significant.

[0058] Statistically significant indicates that differences in yield are due to the treatment effect rather than due to chance. It is relevant to note that there is always a trend towards greater yield under added FAR light even if the difference is not statistically significant, because it occurs across the board it does indicate yield enhancement even at small effect sizes (percent differences in yield).

[0059] The tests also considered comparing 100 PPFD without FAR light to 200 PPFD with FAR light. The reason being that increases in height can also be created by supplying lower PPFDs. In these cases (three trials total including radish, kohlrabi, and broccoli), there was a trend towards greater yield under the 200 PPFD condition with added FAR light compared to the 100 PPFD condition without added FAR light, in radish and kohlrabi this trend was statistically significant, whereas in broccoli the trend was present but it was not statistically significant. The foregoing results were not previously understood and the present invention seeks to benefit from such results and realizations.

[0060] Additional data on dry matter content and cotyledon size is variable and inconsistent with respect to treatment. Changes in cotyledon size and dry matter content do not appear to be consistently related to FAR light treatments. In some treatments FAR light-treated plants had larger cotyledons, and in other cases the cotyledons were smaller. Therefore, risks of altering cotyledon size appear minimal. However, if harvesting plants at a younger age, it is likely that cotyledon size would decrease due to harvesting at an earlier developmental stage.

[0061] Figs. 11-14 are graphs of experimental results for the cultivars kohlrabi, kale, radish, and broccoli, respectively. The graphs illustrate the canopy height (in cm) of each cultivar as a function of time (the number of days after seeding). Two conditions are illustrated in each graph. The first condition (labeled as 3%) is the control condition using only wide-spectrum white light, which has a FAR-PAR ratio of about 3% (e.g., about 2.5%). The second condition (labeled as 7%) is the experimental condition that includes FAR light exposure to provide a FAR-PAR ratio of 7%.

[0062] Broccoli and kohlrabi reached a similar height at 8 days with a FAR-PAR ratio of 7% versus 10 days with broad-spectrum white light. Kale reached a similar height with a FAR-PAR ratio of 7% at 9 days versus 10 days with broad-spectrum white light. Microgreen stages are also more desirable at these cycle lengths.

[0063] Some embodiments and methods using FAR light may allow plants to reach a critical canopy height for harvesting under a shortened cycle time and maintain per year yields and get the product to the desired specification (microgreen stage 1 or 2) rather than the current specs which are microgreen stage 3 or 4 typically (which is undesirable from a microgreen product perspective). This is further illustrated in the table below.

[0064] Figs. 15A-D are side views of simplified illustrations of microgreen stages 1 -4, respectively, according to an embodiment. In stage 1 , only the cotyledons (embryonic leaves) 1510 appear on the stem 1500. In stage 2, signs of the first true leaf 1520 appear on the stem 1500. In stage 3, the first true leaf 1520 has fully expanded. In stage 4, two true leaves 1520 appear on the stem 1500.

[0065] Cotyledons (also known as seed leaves) are plant organs that actually exist in the seed itself and serve to allow the plant to start growing. Cotyledons physically look different from true leaves, and the cotyledon's physical appearance depends on the cultivar. For example, in the case of a Brassica plant, the cotyledon is typically heart shaped. In addition, cotyledons typically fall off the plant once enough true leaves have been established to conduct photosynthesis. While cotyledons can perform photosynthesis, they typically are understood to do it less so than true leaves and instead tend to have resource reserves that are used to feed the plant until the plant is established with leaves.

[0066] Another experiment was run to determine, assuming cycle-time reduction with FAR light is possible (i.e. biomass is similar at reduced cycle time compared to current production time), whether there are any perceived flavor differences when crops are grown under FAR light vs the white light control (broad-spectrum white light). The crops under the white light control were grown for a 10-day cycle (for 10 days after seeding). The crops under the experimental FAR light condition were grown for an 8- day cycle (for 8 days after seeding).

[0067] Broccoli, kohlrabi, and mustard (the only cultivars tested) had no detectable sensory differences in the foregoing tests. This indicates that these plants can be grown using FAR light without having consumers note any differences in the flavor, so while there may be biochemical differences, these at least did not seem to be driving any perceptible changes in the cultivars grown for sensory evaluation.

[0068] Based on these experiments, it was determined that FAR light effectiveness is likely dependent on overall PPFD (irradiance) where under low irradiance the benefit is not realized. The experiments only tested up to 200 PPFD so the effect of higher radiance is not known. Therefore, in an aspect, the present benefit was greater under 200 PPFD than under 100 PPFD.

[0069] The added FAR light may not have a dilution effect and sensory differences in broccoli, kohlrabi, and mustard did not exhibit any perceivable differences (via a tetrad test). Some participants did correctly identify the different product and this tended to be mostly due to flavor attributes, so some differences in glucosinolates (the major flavor contributor in brassica vegetables) may occur, but that this difference overall is not perceptibly different. Further understanding of the differences in the glucosinolate profile in FAR-augmented production systems are possible using the present tests and methods. In non-brassica plants (i.e. sorrel) a benefit was also seen, however since sorrel is a non-glucosinolate producing plant it is not subject to the same assumptions regarding these compounds.

[0070] FAR light will likely benefit yield and allow yield maintenance under reduced cycle times to achieve a more desirable microgreen product but this will depend on the cultivar. No negative effect in yield has been observed. Rather, in some cases, like in radish, the impact of FAR was negligible. However, in most crops trialed there was an increase in yield when grown under added FAR light.

[0071] Fig. 16 is a flow chart of a method 1600 for improving the yield of shortcycle plants (e.g., leafy greens) according to an embodiment. The method 1600 can be performed using indoor growing system 10 or 80.

[0072] In step 1610, broad-spectrum white light is produced with a plurality of white light sources. The white light sources can be the same as white lights 122. The broad-spectrum white light has a wavelength range of 350 nm to 800 nm and a FARRAR ratio of about 3%. For example, the wavelength range of the broad-spectrum white light can be greater than or equal to 350 nm and less than or equal to 800 nm, including 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, or any value or range between any two of the foregoing wavelengths. The broad-spectrum white light can have the same spectrum as example spectrum 20.

[0073] In step 1620, FAR light is produced with a plurality of FAR light sources.

The FAR lights sources can be the same as FAR lights 124. The FAR light has a wavelength range of 700 nm to 750 nm. For example, the wavelength range of the FAR light can be greater than or equal to 700 nm and less than or equal to 750 nm, including 710 nm, 720 nm, 730 nm, 740 nm, or any value or range between any two of the foregoing wavelengths. In another embodiment, the FAR light can have a wavelength range of 700 nm to 800 nm. For example, the wavelength range of the FAR light can be greater than or equal to 700 nm and less than or equal to 800 nm, including 710 nm, 720 nm, 730 nm, 740 nm, 750 nm, 760 nm, 770 nm, 780 nm, 790 nm, or any value or range between any two of the foregoing wavelengths. The FAR light can have the same spectrum as example spectrum 30.

[0074] In step 1630, the plants, including the seeds and seedlings, are exposed to a combined light that includes the broad-spectrum white light and the FAR light. The combined light has a PPFD of about 200 and a FAR-PAR ratio of about 5% to about 30%. The plants are exposed to the combined light in a controlled light environment such as a container in a vertical indoor farm.

[0075] It is noted that initially the seeds may be located in a growing media in which case the seeds are indirectly exposed to the combined light. The plants can be exposed to the combined light for a predetermined time period each day for a predetermined number of days. An example range of the predetermined time period of exposure to the combined light in a day of exposure is about 8 hours to about 24 hours. The plants can be exposed to the combined light for the predetermined time period each day for a predetermined number of days, such as about 6 days to about 12 days. The predetermined number of days is considered to be a short cycle.

[0076] In optional step 1640, the plants are harvested with a mechanical harvester. The plants can be harvested after a predetermined number of days of exposure to the combined light. The plants can be exposed to the combined light for a predetermined time period in each day of exposure.

[0077] Fig. 17 is a flow chart of a method 1700 for improving the yield of shortcycle plants (e.g., leafy greens) according to another embodiment. The method 1700 can be performed using indoor growing system 10 or 80.

[0078] In step 1710, light is produced with a plurality of variable-frequency light sources. The variable-frequency light sources can be the same as grow lights 120. The lights are controlled (e.g., with a controller) such that the produced light has a PPFD of about 200 and a FAR-PAR ratio of about 5% to about 30%. The wavelength range of the light produced in step 1710 can be greater than or equal to 350 nm and less than or equal to 800 nm, including 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, or any value or range between any two of the foregoing wavelengths.

[0079] In step 1720, the plants, including the seeds and seedlings, are exposed to the light in a controlled light environment such as a container in a vertical indoor farm.

[0080] It is noted that initially the seeds may be located in a growing media in which case the seeds are indirectly exposed to the light. The plants can be exposed to the light for a predetermined time period each day for a predetermined number of days. An example range of the predetermined time period of exposure to the light in a day of exposure is about 8 hours to about 24 hours. The plants can be exposed to the light for the predetermined time period each day for about 6 days to about 12 days.

[0081] In optional step 1730, the plants are harvested with a mechanical harvester. The plants can be harvested after a predetermined number of days of exposure to the light. The plants can be exposed to the light for a predetermined time period in each day of exposure.

[0082] A further advantage and aspect of some embodiments is that the system and method described herein can be networked to other machines or human users and data storage systems and processors. For example, the present method and system can be controlled and updated or monitored remotely over such data communication networks using data communication interfaces. Software applications or apps can be used to accept management settings, make changes to operations of the method and system, report status and alarms or warnings, and other communication functions.

[0083] The invention should not be considered limited to the particular embodiments described above. Various modifications, equivalent processes, as well as numerous structures to which the invention may be applicable, will be readily apparent to those skilled in the art to which the invention is directed upon review of this disclosure. The above-described embodiments may be implemented in numerous ways. One or more aspects and embodiments involving the performance of processes or methods may utilize program instructions executable by a device (e.g., a computer, a processor, or other device) to perform, or control performance of, the processes or methods.

[0084] In this respect, various inventive concepts may be embodied as a non- transitory computer readable storage medium or multiple non-transitory computer readable storage media, e.g., a computer memory of any suitable type including transitory or non-transitory digital storage units, circuit configurations in Field Programmable Gate Arrays or other semiconductor devices, or other tangible computer storage medium, encoded with one or more programs that, when executed on one or more computers or other processors, perform methods that implement one or more of the various embodiments described above. When implemented in software (e.g., as an app), the software code may be executed on any suitable processor or collection of processors, whether provided in a single computer or distributed among multiple computers.

[0085] Also, the present processing components may have one or more communication devices, which may be used to interconnect the computer to one or more other devices and/or systems, such as, for example, one or more networks in any suitable form, including a local area network or a wide area network, such as an enterprise network, and intelligent network (IN) or the Internet. Such networks may be based on any suitable technology and may operate according to any suitable protocol and may include wireless networks or wired networks.

[0086] Additionally, a processor as may be used herewith can have one or more input devices and/or one or more output devices. These devices can be used, among other things, to present a user interface. Examples of output devices that may be used to provide a user interface include printers or display screens for visual presentation of output and speakers or other sound generating devices for audible presentation of output. Examples of input devices that may be used for a user interface include keyboards, and pointing devices, such as mice, touch pads, and digitizing tablets. As another example, a computer may receive input information through speech recognition or in other audible formats.

[0087] The non-transitory computer readable medium or media may be transportable, such that the program or programs stored thereon may be loaded onto one or more different computers or other processors to implement various one or more of the aspects described above. In some embodiments, computer readable media may be non- transitory media.

[0088] The terms "program," "app," and "software" are used herein in a generic sense to refer to any type of computer code or set of computer-executable instructions that may be employed to program a computer or other processor to implement various aspects as described above. Additionally, it should be appreciated that, according to one aspect, one or more computer programs that when executed perform methods of this application need not reside on a single computer or processor, but may be distributed in a modular fashion among a number of different computers or processors to implement various aspects of this application.

[0089] Computer-executable instructions may be in many forms, such as program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that performs particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or distributed as desired in various embodiments.

[0090] Also, data structures may be stored in computer-readable media in any suitable form. For simplicity of illustration, data structures may be shown to have fields that are related through location in the data structure. Such relationships may likewise be achieved by assigning storage for the fields with locations in a computer-readable medium that convey relationship between the fields. However, any suitable mechanism may be used to establish a relationship between information in fields of a data structure, including through the use of pointers, tags or other mechanisms that establish relationship between data elements. [0091] Thus, the disclosure and claims include new and novel improvements to existing methods and technologies, which were not previously known nor implemented to achieve the useful results described above. Users of the method and system will reap tangible benefits from the functions now made possible on account of the specific modifications described herein causing the effects in the system and its outputs to its users. It is expected that significantly improved operations can be achieved upon implementation of the claimed invention, using the technical components recited herein.

[0092] Also, as described, some aspects may be embodied as one or more methods. 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.

[0093] What is claimed is:

Claims

1 . A method for enhancing a yield of short-cycle plants, comprising: providing a broad-spectrum white light with a plurality of white light sources, the broad-spectrum white light having a wavelength range that is greater than or equal to 350 nm and less than or equal to 800 nm and a FAR-PAR ratio of about 3%, wherein:

FAR is far-red light having a wavelength range that is greater than or equal to 700 nm and less than or equal to 750 nm, and

PAR is photosynthetically active radiation having a wavelength range that is greater than or equal to 400 nm and less than or equal to 700 nm; producing FAR light with a plurality of FAR light sources; and exposing the plants to a combined light for a predetermined time period each day for a predetermined number of days, the combined light comprising the broadspectrum white light and the FAR light, the combined light having a photosynthetic photon flux density of about 200 and a FAR-PAR ratio of about 5% to about 30%.

2. The method of claim 1 , wherein the white light sources and the FAR light sources are mounted on a common light fixture.

3. The method of claim 1 , wherein the white light sources comprise white light-emitting diodes (LEDs) and the FAR light sources comprise FAR LEDs.

4. The method of claim 3, wherein the white LEDs and the FAR LEDs are fixed- spectrum LEDs.

5. The method of claim 1 , further comprising harvesting the plants with a mechanical harvester.

6. The method of claim 1 , wherein: the predetermined time period is about 8 hours to about 24 hours, and the predetermined number of days is about 6 days to about 12 days.

7. The method of claim 1 , further comprising placing the plants in a chamber having a controlled light environment.

8. The method of claim 1 , wherein the plants comprise Brassica plants and/or Brassicaceae plants.

9. The method of claim 8, further comprising placing the plants in a chamber having a controlled light environment.

10. A method for enhancing a yield of short-cycle plants, comprising: producing a light with a plurality of variable-frequency light sources, the light having a photosynthetic photon flux density of about 200 and a FAR-PAR ratio of about 5% to about 30%, wherein:

FAR is far-red light having a wavelength range of greater than or equal to 700 nm to and less than or equal to 750 nm, and

PAR is photosynthetically active radiation having a wavelength range of greater than or equal to 400 nm to and less than or equal to 700 nm; and exposing the plants to the light for a predetermined time period each day for a predetermined number of days.

11 . The method of claim 10, wherein the variable-frequency light sources comprise variable-frequency light-emitting diodes.

12. The method of claim 10, further comprising harvesting the plants with a mechanical harvester.

13. The method of claim 10, further comprising placing the plants in a chamber having a controlled light environment.

14. A system for enhancing a yield of short-cycle plants under artificial light, comprising: a plurality of light emitting diodes (LEDs) providing said artificial light, including a plurality of broad-spectrum white light LEDs delivering a first light output covering a wavelength range between 350 nm and 800 nm, and having a FAR-PAR ratio of about 3% from said white light LEDs where said PAR comprises photosynthetically active radiation having a wavelength range between 400 nm and 700 nm; a plurality of far-red LEDs delivering a second light output covering a FAR wavelength range between 700 nm and 750 nm; a processor-based controller, configured and arranged to receive input signals, execute programmed machine readable instructions and to provide output control signals, said controller programmably outputting one or more control signals to control said broad-spectrum white LEDs and said far-red LEDs; and wherein said one or more control signals determine a first intensity of said first light output and a second intensity of said second light output, and wherein said one or more control signals modulate said first and second intensities so as to achieve a FAR-PAR ratio of at least 5% from both said plurality of while light LEDs and said plurality of far-red LEDs.