Patent Publication Number: US-2021161090-A1

Title: High-density cultivation system, apparatus used therein, and methods of operation thereof

Description:
FIELD OF TECHNOLOGY 
     The present disclosure relates generally to the field of high-density plant cultivation, and, more specifically, to an improved high-density soil-less hydroponic cultivation system, apparatus used therein, and methods of operation thereof. 
     BACKGROUND 
     High-density plant cultivation usually refers to the cultivation of plants in a small indoor environment, often in the absence of soil. Plants in such an environment are often grown vertically using hydroponics and artificial grow lights. Indoor vertical cultivation offers advantages to conventional outdoor soil-based cultivation since growers are free from having to deal with insects, invasive weeds, or soil-borne pests, thereby reducing the need for harmful insecticides or herbicides. 
     However, most traditional high-density plant cultivation systems are often beset with a litany of problems including root rot, the spread of bacteria through contaminated water, plants suffering from heat stress, and high water and electricity bills. The latter problem is often the result of cultivation systems that waste water or are not efficient in their water usage. In addition, while artificial lights such as high-pressure sodium lamps or metal halide lamps can mimic natural outdoor sunlight, such lights can also raise the temperature of an indoor grow environment above ideal temperature ranges and cause heat damage to young plants. Traditional high-density cultivation systems are often set up such that certain plants within the grow environment are exposed to too much light while other plants are exposed to too little light. Furthermore, most traditional hydroponic systems are designed such that components of the system cannot be cleaned or disassembled for cleaning unless all plant matter is removed from the system. This can make it difficult to maintain the system on a regular basis without disturbing the grow environment. 
     Therefore, a solution is needed which addresses the above shortcomings and disadvantages. Such a solution should optimize water and energy usage, control the amount of heat generated by artificial lights, and reduce any disparities in light exposure. In addition, such a system should be easy to disassemble for cleaning and maintenance and easy to re-assemble when done. Such a system, including components used therein, should be cost-effective to manufacture and not overly complicated to operate. 
     SUMMARY 
     Disclosed are high-density soil-less hydroponic cultivation systems, apparatus, and devices used by such systems, and methods of cultivating plants in a high-density environment without soil. In some embodiments, the high-density soil-less hydroponic cultivation system disclosed herein can be used to cultivate plants of the genus  Cannabis  including  Cannabis sativa  plants,  Cannabis indica  plants, or hybrids thereof. In other embodiments, the high-density soil-less hydroponic cultivation system disclosed herein can also be used to cultivate, inter alia, beets, tomatoes, eggplants, lettuce, kale, basil and other herbs, strawberries, blueberries, cucumbers, pumpkins, or watermelons. 
     In one embodiment, the high-density cultivations system comprises one or more grow columns, each having a column lumen, and one or more angled housings coupled to the grow columns. The grow columns can each be made in part of a plurality of detachable column segments connected by column couplers. At least one angled housing can be coupled to one of the plurality of detachable column segments. 
     Each of the angled housings can comprise a housing lumen in fluid communication with the column lumen. Each of the angled housings can be configured to accommodate at least one plant or plantlet. In some embodiments, the housing lumen can allow the roots of the plant to grow deeper into the housing lumen. In other embodiments, the housing lumen and the column lumen can both allow the roots of the plant to grow deeper into such lumens. 
     At least one of the angled housings can comprise a basket having one or more perforations along at least one of a bottom and side of the basket. The basket can be positioned within at least part of the housing lumen. The basket can be configured to hold the plant matter and accommodate root growth further into the housing lumen. 
     One or more angled housings can also comprise a light-blocking collar configured to block or obstruct light from entering the housing lumen. The light-blocking collar can have a port configured to allow at least part of the plant to extend through the port. In some embodiments, the light-blocking collar can be made in part of a water-resistant synthetic rubber such as polychloroprene (e.g., Neoprene®) or an elastomeric polymer such as ethylene-vinyl acetate. In other embodiments, at least one angled housing can comprise a porous reticulated foam support. The porous reticulated foam support can occupy at least part of the housing lumen and can be defined by a cavity or channel configured to accommodate plant matter. 
     The system can also comprise a nutrient reservoir configured to contain a nutrient solution to be delivered to the grow columns. The nutrient reservoir can be in fluid communication with or fluidly coupled to the grow columns via one or more fluid delivery pipes or conduits. 
     At least a segment of a fluid delivery pipe can be positioned above a column lumen of a grow column. The system can further comprise a spray sprinkler coupled to the segment of the fluid delivery pipe positioned above the column lumen. The spray sprinkler can be configured to spray the nutrient solution flowing through the fluid delivery pipe into the column lumen. 
     In some embodiments, the spray sprinkler can spray the nutrient solution into the column lumen periodically, intermittently, or a combination thereof. The spray sprinkler can spray the nutrient solution into the column lumen at intervals or periodically such that spray periods are followed by dry periods where no nutrient solution is delivered into the column lumen. For example, the spray sprinkler can spray the nutrient solution into the column lumen between about 10 minutes to about 15 minutes every sixty minutes. In other embodiments, the spray sprinkler can spray the nutrient solution into the column lumen between about 30 seconds to about 45 seconds every 5 minutes. 
     The system can further comprise a liquid cooling unit, such as a water chiller, for cooling the nutrient solution between about 65 degrees to about 68 degrees Fahrenheit. The liquid cooling unit can be in fluid communication with the nutrient reservoir such that the nutrient solution is circulated through the liquid cooling unit to be cooled. 
     The system can further comprise one or more capture conduits or pipes coupled to the grow columns. The capture conduits can comprise capture lumens in fluid communication with the column lumens. The capture conduits can be configured to capture (and recapture) nutrient solution flowing through the grow columns. In one embodiment, the capture conduits can be positioned beneath the grow columns. 
     The system can also comprise a capture reservoir configured to collect the captured or recaptured nutrient solution from the capture conduits. The captured or recaptured nutrient solution can be collected to be delivered to the nutrient reservoir for reuse. The capture reservoir can comprise a reservoir inlet. The reservoir inlet can be covered by a submersible filter configured to capture and filter out particulates from the captured or recaptured nutrient solution collected by the capture conduits. 
     The system can further comprise an omnidirectional light tower configured to shine light on the one or more angled housings to induce plant growth within the angled housings. In some embodiments, the omnidirectional light tower can be surrounded (e.g., on four sides) or encircled by a plurality of grow columns. In these embodiments, the angled housings can extend toward the omnidirectional light tower such that foliage of plant matter contained within the angled housings are exposed to light emitted by the omnidirectional light tower. 
     The omnidirectional light tower can comprise a columnar housing extending vertically and at least two types of high-intensity discharge (HID) lamps positioned vertically in an alternating manner within the columnar housing. At least part of the columnar housing comprising the HID lamps can be transparent. In some embodiments, the two types of HID lamps can comprise high-pressure sodium (HPS) lamps and dual arc hybrid lamps. In these embodiments, the HPS lamps and the dual arc hybrid lamps can be positioned in an alternating manner vertically within the columnar housing. 
     In certain embodiments, the dual arc hybrid lamp can be a combination HPS and metal halide (MH) lamp. In other embodiments, the dual arc hybrid lamp can be a combination HPS and ceramic metal halide (CMH) lamp. 
     The omnidirectional light tower can also comprise an activated-carbon air filter serving as a base of the omnidirectional light tower. The activated-carbon air filter can comprise a filter housing surrounding a filter cavity comprising activated carbon. In some embodiments, the activated-carbon air filter can also have a cloth filter or mesh filter covering the filter housing. 
     The filter cavity can be in fluid communication with a housing space within the columnar housing. The HID lamps, including the HPS lamps and the dual arc hybrid lamps, can be housed within the housing space. The omnidirectional light tower can also comprise an inline duct fan positioned above the HID lamps. Moreover, the inline duct fan can be in fluid communication with the housing space. 
     The inline duct fan can be configured to cool the omnidirectional light tower and ventilate an indoor grow environment by drawing in air through the activated-carbon air filter into the filter cavity and up through the housing space to be expelled outside of the indoor grow environment. 
     A method of cultivating plants without soil is also disclosed. The method comprises providing one or more grow columns, each comprising a column lumen, and an omnidirectional light tower. The method can also comprise positioning the one or more grow columns and the one or more angled housings coupled to the grow columns such that the angled housings extend toward or face the omnidirectional light tower. Each of the angled housings can comprise a housing lumen in fluid communication with the column lumen. Each of the angled housings can be configured to accommodate plant matter. At least one of the column lumen and the housing lumen can be configured to accommodate root growth of the plant matter within the angled housing into such lumens. 
     The method can also comprise delivering a nutrient solution from a nutrient reservoir to the grow columns. The nutrient solution can be delivered to the grow columns via one or more fluid delivery pipes in fluid communication with the nutrient reservoir. 
     The method can also comprise cooling the nutrient solution to between about 65 degrees to about 68 degrees Fahrenheit by circulating the nutrient solution through a liquid cooling unit in fluid communication with the nutrient reservoir. The nutrient solution can be cooled or chilled prior to being delivered to the grow columns. 
     At least one segment of a fluid delivery pipe can be positioned above a column lumen of a grow column. The method can further comprise spraying the nutrient solution flowing through the fluid delivery pipe into the column lumen using a spray sprinkler coupled to the segment of the fluid delivery pipe positioned above the column lumen. In some embodiments, each column lumen can have at least one spray sprinkler positioned above the column lumen to spray nutrient solution into the column lumen. 
     The nutrient solution can be sprayed into each column lumen periodically such that spray periods are followed by dry periods where no nutrient solution is delivered into the column lumen. 
     In addition, the method can comprise capturing (and eventually, recapturing) nutrient solution flowing through the grow columns. The method can further comprise delivering the captured or recaptured nutrient solution to the nutrient reservoir for reuse as the nutrient solution. The method can also comprise filtering the captured or recaptured nutrient solution prior to delivering the captured or recaptured nutrient solution to the nutrient reservoir for reuse. 
     The method can further comprise surrounding the omnidirectional light tower on at least two sides with a plurality of grow columns. The angled housings of the grow columns can be positioned such that the angled housings extend toward or face the omnidirectional light tower and the leaves of plant matter within such angled housings are exposed to light emitted by the omnidirectional light tower. 
     The omnidirectional light tower can comprise a columnar housing extending vertically upward. The omnidirectional light tower can also comprise at least two types of high-intensity discharge (HID) lamps positioned vertically in an alternating manner within the columnar housing. Parts of the columnar housing comprising the HID lamps can be transparent. In some embodiments, the two types of HID lamps can comprise high-pressure sodium (HPS) lamps and dual arc hybrid lamps. In these embodiments, the HPS lamps and the dual arc hybrid lamps can be positioned in an alternating manner vertically within the columnar housing. 
     The omnidirectional light tower can be cooled by drawing in air through one or more filter surfaces of an activated-carbon air filter serving as a base of the omnidirectional light tower. The air can be drawn in by an inline duct fan positioned above the HID lamps. The activated-carbon air filter can comprise a filter cavity comprising activated carbon. The filter cavity can be in fluid communication with a housing space within the columnar housing. The HID lamps, including the high-pressure sodium lamps and the dual arc hybrid lamps, can be contained within the housing space. The inline duct fan can be in fluid communication with the housing space such that air drawn in through the activated-carbon air filter is drawn up through the housing space of the column housing and then expelled through air ducts. This can ventilate an indoor grow environment and remove heat generated by the HID lamps. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an improved high-density plant cultivation system. 
         FIG. 2A  illustrates embodiments of a nutrient reservoir and a liquid cooling unit of the system of  FIG. 1 . 
         FIG. 2B  illustrates embodiments of a capture reservoir comprising a submersible filter of the system of  FIG. 1 . 
         FIG. 3  illustrates a plurality of grow columns comprising angled housings. 
         FIG. 4A  illustrates a close-up view of an angled housing. 
         FIG. 4B  illustrates a basket configured to be placed within the angled housing. 
         FIG. 4C  illustrates an angled housing comprising a light-blocking collar and a plantlet extending through a port along the light-blocking collar. 
         FIG. 4D  illustrates an angled housing comprising a porous reticulated foam support for supporting plant matter. 
         FIG. 5  illustrates a plurality of grow columns surrounding an embodiment of an omnidirectional light tower comprising an activated-carbon air filter serving as a base of the omnidirectional light tower. 
         FIG. 6  illustrates the top of the omnidirectional light tower comprising an inline duct fan. 
         FIG. 7  is a black-and-white image of plants growing out of the angled housings of a plurality of grow columns. 
         FIG. 8  is a black-and-white image of a root column extracted from a column lumen of a grow column. 
         FIG. 9  is an embodiment of a method of cultivating plants or plant matter without soil. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a schematic illustration of an improved high-density plant cultivation system  100 . The system  100  can comprise a plurality of grow columns  102  with each grow column  102  having a column lumen  104 . The grow columns  102  can be made in part of a polymeric material or another type of corrosion-resistant material. For example, the grow columns  102  can be made in part of polyvinyl chloride (PVC). In some embodiments, the grow columns  102  can be substantially cylindrical-shaped having a column diameter. For example, the grow columns  102  can be cylindrical columns having a column diameter of between about 3 inches (76 mm) to about 4 inches (102 mm). More specifically, the grow columns  102  can be 3-inch PVC pipes. 
     The system  100  can also comprise a plurality of angled housings  106  coupled to the grow columns  102  or extending from the grow columns  102 . In some embodiments, the angled housings  106  can be angled pipe fittings attached to segments of piping configured to be connected to a grow column  102 . In these embodiments, the angled housings  106  can be 3-inch PVC Wye fittings. In other embodiments, the angled housings  106  can be coupled to a grow column  102  by being inserted an angle into openings or perforations defined along a length of the grow column  102 . In certain embodiments, the angled housings  106  can be positioned at an angle with respect to a longitudinal axis of the grow column  102 . This angle can be about 45 degrees with respect to the longitudinal axis of the grow column  102 . In other embodiments, the angle can be between about 25 degrees to about 45 degrees or between about 45 degrees and 60 degrees. 
     Each of the angled housings  106  can comprise a housing lumen  108  in fluid communication with the column lumen  104 . The angled housings  106  can be configured to accommodate plant matter. For example, each of the angled housings  106  can be configured to accommodate a plantlet such as a young  Cannabis  clone. The housing lumen  108  can allow the roots of the plant or plantlet to grow further into the housing lumen  108 . In addition, the housing lumen  108  can allow the roots of the plant or plantlet to grow through the entirety (i.e., through the entire length) of the housing lumen  108  and into the column lumen  104 . 
     The system  100  can also comprise a nutrient reservoir  110 . The nutrient reservoir  110  can be a container, tank, or basin for holding a nutrient solution  112  (the nutrient solution  112  is depicted in  FIG. 1  using short straight-arrows. The direction of nutrient solution flow within the system  100  is also indicated using such arrows). 
     In some embodiments, the nutrient reservoir  110  can be a tank or container made in part of a non-corrosive or inert material. The nutrient reservoir  110  can have a nutrient reservoir volume. For example, the nutrient reservoir volume can be between about 30 gallons (114 L) to about 100 gallons (378 L). More specifically, the nutrient reservoir volume can be about 50 gallons (189 L). 
     The nutrient solution  112  can be an aqueous solution made in part of a diluted plant food concentrate or liquid fertilizer. In some embodiments, the nutrient solution  112  can comprise nitrogen (ammoniacal nitrogen and/or nitrate nitrogen), potassium (or soluble potash), calcium, magnesium, phosphates, molybdenum, or a combination thereof. The composition of the nutrient solution  112  within the nutrient reservoir  110  can be altered on a daily, weekly, or monthly basis. 
     Water used to make the nutrient solution  112  can be filtered or purified using a water filtration system  114 . In some embodiments, the water filtration system  114  can be a reverse osmosis filtration system. For example, the water filtration system  114  can be a GrowoniX™ reverse osmosis filtration system capable of filtering between about 1500 gallons per day (GPD) to 2000 GPD of water from a water source, such as the tap. 
     The nutrient solution  112  within the nutrient reservoir  110  can have a pH of about 7. In certain circumstances, the pH of the nutrient solution  112  within the nutrient reservoir  110  can be between about pH 6.8 to about pH 7.2. 
     The system  100  can further comprise a liquid cooling unit  116 , such as a water chiller, configured to cool the nutrient solution  112  within the nutrient reservoir  110  to be between about 65 degrees to about 68 degrees Fahrenheit. The liquid cooling unit  116  can be in fluid communication with the nutrient reservoir  110  such that the nutrient solution  112  is continuously circulated through the liquid cooling unit  116  to be cooled. In some embodiments, the liquid cooling unit  116  can be a freon-free water chiller capable of accommodating a flow rate of between about 400 gallons per hour (GPH) to about 4000 GPH. 
     As will be discussed in more detail in the following sections, the system  100  can capture or recapture nutrient solution  112  that has flowed through the grow columns  102 . The captured or recaptured nutrient solution can be first collected in a capture reservoir  130  and then delivered back into the nutrient reservoir  110 . The temperature of the recaptured nutrient solution can be higher than 68 degrees Fahrenheit as a result of the solution coming into contact with various pipes, plant roots, and pumps and the friction caused by such contact. Moreover, the captured or recaptured nutrient solution can also be warmed by the higher temperature within the indoor environment housing the grow columns  102 . The liquid cooling unit  116  can be used to cool new instances of the nutrient solution  112  as well as captured or recaptured nutrient solution introduced into the nutrient reservoir  110  (when the captured or recaptured nutrient solution is introduced into the nutrient reservoir  110 , the resulting solution can once again be referred to as the nutrient solution  112  for purposes of this disclosure). The liquid cooling unit  116  can be configured to ensure that the nutrient solution  112  delivered to the grow columns  102  (whether new instances of the nutrient solution  112  or the captured/recaptured nutrient solution) is cooled to between about 65 degrees to about 68 degrees Fahrenheit. The system  100  can comprise multiple liquid cooling units  116  including one or more backup liquid cooling units  116  in case the main liquid cooling unit  116  is non-functional or out of operation. 
     The nutrient solution  112  within the nutrient reservoir  110  can also be aerated or oxygenated by an aerator or oxygenation unit. The aerator or oxygenation unit can ensure that the nutrient solution  112  within the nutrient reservoir  110  is oxygenated prior to reaching the grow columns  102 . 
     The nutrient reservoir  110  can be in fluid communication with or fluidly coupled to the grow columns  102  via one or more fluid delivery pipes  118  or conduits. The nutrient solution  112  within the nutrient reservoir  110  can be pumped to the grow columns  102  using one or more pumps  120  fluidly coupled to the nutrient reservoir  110 . For example, the pumps  120  can be centrifugal pumps comprising impellers or impeller vanes. An inlet of the pump  120  can extend into the nutrient reservoir  110  and an outlet of the pump  120  can be fluidly coupled to the fluid delivery pipes  118 . 
     The fluid delivery pipes  118  can allow the nutrient solution  112  to flow from the nutrient reservoir  110  into an indoor grow environment comprising the grow columns  102 . For example, the indoor grow environment can be an enclosed indoor space, such as a room or part of a room. In some embodiments, the indoor grow environment can be a room separate from the room where the nutrient reservoir  110  is located. In other embodiments, the nutrient reservoir  110  can be located in the same room as the grow columns  102 . 
     One or more segments of the fluid delivery pipes  118  can be positioned vertically above the column lumens  104  of the grow columns  102 . In these embodiments, the column lumens  104  can be exposed or left open at a top end or superior end of the column lumens  104 . 
     The system  100  can further comprise a plurality of spray sprinklers  122  coupled to the segments of the fluid delivery pipes  118  positioned above the column lumens  104 . Each spray sprinkler  122  can be positioned vertically above a column lumen  104  of a grow column  102 . In some embodiments, at least part of each spray sprinkler  122  can extend into part of the column lumen  104 . In all such embodiments, the spray sprinklers  122  are positioned vertically above the highest angled housings  106  coupled to the grow columns  102 . 
     The spray sprinklers  122  can be configured to spray the nutrient solution  112  flowing through the fluid delivery pipes  118  into the column lumens  104 . In some embodiments, the spray sprinklers can be full pattern or full-circle (360 degrees) pattern sprinklers. More specifically, the spray sprinklers can be Orbit® full pattern shrub sprinklers. 
     The system  100  can be configured such that the spray sprinklers  122  spray or sprinkle the nutrient solution  112  into the column lumens  104  periodically. In other embodiments, the spray sprinklers  122  can be configured to spray or sprinkle the nutrient solution  112  into the column lumens  104  intermittently, or both periodically and intermittently. The spray sprinklers  122  can be controlled by a timer or timing mechanism. 
     The spray sprinklers  122  can spray the nutrient solution  112  into the column lumens  104  at intervals or periodically such that spray periods are followed by dry periods where no nutrient solution  112  is delivered into the column lumens  104 . This can allow the roots of the plant matter housed within the angled housings  106  to dry up or begin to dry in between the spray periods. Doing so can improve the root health of such plants and improve water uptake. 
     For example, the spray sprinklers  122  can spray the nutrient solution  112  into the column lumens  104  between about 10 minutes to about 15 minutes every sixty minutes. In other embodiments, the spray sprinklers  122  can spray the nutrient solution  112  into the column lumens  104  between about 30 seconds to about 45 seconds every 5 minutes. The spray sprinklers  122  can also follow other periodic spraying schedules. 
     By spraying or sprinkling the nutrient solution  112  into the column lumens  104 , the nutrient solution  112  can also be oxygenated or aerated prior to reaching the plant roots. Moreover, spraying or sprinkling the nutrient solution  112  into the column lumens  104  from above in this manner also ensures the nutrient solution  112  reaches all areas within each column lumen  104  and root growth is even and uniform within the column lumen  104 . 
     One unexpected result discovered by the applicants is that spraying or sprinkling the nutrient solution  112  into the column lumens  104  of the grow columns  102  increased yields and generally improved plant health while significantly reducing water usage and waste. 
     The system  100  can also comprise a carbon dioxide generator  124 . The carbon dioxide generator  124  can be positioned vertically above the grow columns  102 . The system  100  can also comprise one or more fans  126  configured to circulate the carbon dioxide generated by the carbon dioxide generator  124  and blow the carbon dioxide down onto the plants within the angled housings  106 . 
     The system  100  can further comprise one or more capture conduits  128  or capture pipes coupled to the grow columns  102 . The capture conduits  128  can have capture lumens in fluid communication with the column lumens  104 . The capture conduits  128  can be configured to capture (and eventually, recapture) nutrient solution  112  flowing through the column lumens  104 . In some embodiments, the capture conduits  128  can be positioned vertically below the grow columns  102  and rely on gravity to direct the nutrient solution  112  to the capture conduits  128 . In other embodiments, the capture conduits  128  can be coupled to segments of the grow column  102  along the length of the grow column  102  such that excess nutrient solution  112  or unused nutrient solution  112  flows out of the column lumens  104  into the capture conduits  128 . 
     In some embodiments, the capture conduits  128  can be PVC pipes having a pipe diameter slightly larger than the diameter of the grow columns  102  (e.g., about 4 inches or 5 inches). 
     The system  100  can also comprise a capture reservoir  130  configured to collect the captured nutrient solution or recaptured nutrient solution (for purposes of this disclosure, the captured nutrient solution can refer to solution initially captured or collected and the recaptured nutrient solution can refer to solution that has been subsequently captured or collected). The capture conduits  128  can direct the captured or recaptured nutrient solution to a capture reservoir  130 . The captured or recaptured nutrient solution can be collected to be delivered to the nutrient reservoir  110  for reuse (to be recirculated through the fluid delivery pipes  118 , column lumens  104 , and capture conduits  128 ). 
     The capture reservoir  130  can comprise at least one reservoir inlet  132 . In some embodiments, the reservoir inlet  132  can be a distal segment of one of the capture conduits  128 . In other embodiments, the reservoir inlet  132  can be an inlet affixed within the capture reservoir  130 . The reservoir inlet  132  can be covered by a submersible filter  134 . The submersible filter  134  can be submerged in the captured or recaptured nutrient solution within the capture reservoir  130 . 
     The submersible filter  134  can be configured to capture and filter out particulates from the captured or recaptured nutrient solution. For example, the submersible filter  134  can capture and filter out plant debris, insects, or other waste products within the captured or recaptured nutrient solution. The submersible filter  134  can be cleaned or replaced on a periodic or regular basis to ensure the submersible filter  134  can continue to capture and filter out debris and other waste products. The submersible filter  134  will be discussed in more detail in the following section. 
     The capture reservoir  130  can also comprise or be coupled to one or more pumps  136 . In some embodiments, the one or more pumps  136  can be submersible water pumps. In other embodiments, the one or more pumps  136  can be centrifugal water pumps or impeller-type pumps. 
     The pumps  136  can pump the captured or recaptured nutrient solution from the capture reservoir  130  to the nutrient reservoir  110  to be cooled by the cooling unit  116 , aerated, and eventually recirculated back to the grow columns  102 . 
     One unexpected result discovered by the applicants is that separating the capture reservoir  130  from the nutrient reservoir  110  (rather than combining the two reservoirs into one reservoir) improved the health of the plants within the indoor grow environment. For example, separating the capture reservoir  130  from the nutrient reservoir  110  can improve the quality and cleanliness of the recaptured nutrient solution. The capture reservoir  130  can also buffer the nutrient solution  112  within the nutrient reservoir  110  against drastic changes in temperature and can allow the nutrient solution  112  within the nutrient reservoir  110  more time to be cooled by the liquid cooling unit  116  before captured or recaptured nutrient solution is delivered to the nutrient reservoir  110  for reuse. 
     The system  100  can further comprise an omnidirectional light tower  138  configured to shine light on the plants or plantlets within the angled housings  106  coupled to the grow columns  102 . 
     The omnidirectional light tower  138  can be surrounded (for example, on four sides) or encircled by a plurality of grow columns  102 . Although two grow columns  102  are shown in  FIG. 1 , it is contemplated by this disclosure (and shown in  FIGS. 3, 5, 6, and 7 ) that the system  100  can comprise a multitude of grow columns  102 . 
     The angled housings  106  coupled to each of the grow columns  102  can be positioned such that the angled housings  106  extend toward or face the omnidirectional light tower  138 . The angled housings  106  can extend toward the omnidirectional light tower  138  such that foliage of plants or plantlets contained within the angled housings  106  can be exposed to light emitted by the omnidirectional light tower  138 . 
     The omnidirectional light tower  138  can comprise a columnar housing  140  (e.g., glass column or tube) extending vertically and at least two types of high-intensity discharge (HID) lamps positioned vertically in an alternating manner within the columnar housing  140 . In some embodiments, the two types of HID lamps can comprise high-pressure sodium (HPS) lamps  142  and dual arc hybrid lamps  144 . In these embodiments, the HPS lamps  142  and the dual arc hybrid lamps  144  can be positioned in an alternating manner vertically within the columnar housing  140 . At least part of the columnar housing  140  comprising the HID lamps  142  can be transparent. 
     In certain embodiments, the dual arc hybrid lamp  144  can be a combination HPS and metal halide (MH) lamp. In other embodiments, the dual arc hybrid lamp  144  can be a combination HPS and ceramic metal halide (CMH) lamp. 
     The omnidirectional light tower  138  can also comprise an activated-carbon air filter  146  serving as a base of the omnidirectional light tower  138 . The activated-carbon air filter  146  can comprise a filter housing  148  surrounding a filter cavity comprising activated carbon. In some embodiments, the activated-carbon air filter  146  can also have a cloth filter or mesh filter covering the filter housing  148 . 
     The filter cavity can be in fluid communication with a housing space within the columnar housing  140 . The HID lamps, including the HPS lamps  142  and the dual arc hybrid lamps  144 , can be housed within the housing space. 
     The omnidirectional light tower  138  can also comprise an inline duct fan  150  positioned above the HID lamps. Moreover, the inline duct fan  150  can be in fluid communication with the housing space. 
     The inline duct fan  150  can be configured to cool the omnidirectional light tower  138  and, ultimately, cool the indoor grow environment. The inline duct fan  150  can also ventilate the indoor grow environment. The inline duct fan  150  can draw in air through the filter housing  148  of the activated-carbon air filter  146  into the filter cavity. The air drawn in can then be drawn up through the housing space of the columnar housing  140  into air ducts or vents to be expelled outside of the indoor grow environment. The omnidirectional light tower  138  will be discussed in more detail in the following sections. 
       FIG. 2A  illustrates an embodiment of a nutrient reservoir  110  and a liquid cooling unit  116  fluidly coupled to the nutrient reservoir  110 . As previously discussed, the nutrient reservoir  110  can be a container, tank, or basin for holding the nutrient solution  112 . In some embodiments, the nutrient reservoir  110  can be a tank or container made in part of a non-corrosive or inert material such as a polymeric material. For example, the nutrient reservoir  110  can be a tank or container made in part of high-density polyethylene (HDPE), such as food-grade HDPE. 
     The nutrient reservoir  110  can have a nutrient reservoir volume. For example, the nutrient reservoir volume can be between about 30 gallons (114 L) to about 100 gallons (378 L). More specifically, the nutrient reservoir volume can be about 40 gallons (151 L) or about 50 gallons (189 L). 
     The nutrient solution  112  can be an aqueous solution. The nutrient solution  112  can provide all of the nutrients and growth regulators needed by the plants or plantlets housed within the angled housings  106 . In some embodiments, the nutrient solution  112  can comprise nitrogen (ammoniacal nitrogen and/or nitrate nitrogen), potassium (or soluble potash), calcium, magnesium, phosphates, molybdenum, or a combination thereof. The composition of the nutrient solution  112  within the nutrient reservoir  110  can be altered on a daily, weekly, or monthly basis. 
     Water used to make the nutrient solution  112  can be filtered or purified using a reverse osmosis filtration or purification system prior to being added to the nutrient reservoir  110 . The nutrient solution  112  can be made in part of tap water filtered using the reverse osmosis filtration or purification system. 
     The nutrient solution  112  within the nutrient reservoir  110  can have a pH of about 7. In certain circumstances, the pH of the nutrient solution  112  within the nutrient reservoir  110  can be between about pH 6.8 to about pH 7.2. 
     The system  100  can further comprise a liquid cooling unit  116 , such as one or more water chillers (e.g., a primary water chiller and a backup water chiller). The liquid cooling unit  116  can be configured to cool the nutrient solution  112  within the nutrient reservoir  110  to between about 65 degrees to about 68 degrees Fahrenheit (about 18 degrees to about 20 degrees Celsius). The nutrient solution  112  can be pumped into the liquid cooling unit  116 , cooled within the liquid cooling unit  116 , and then pumped back into the nutrient reservoir  110 . The nutrient solution  112 , including the captured or recaptured nutrient solution from the capture reservoir  130 , can be continuously circulated through the liquid cooling unit  116 . 
     In some embodiments, the liquid cooling unit  116  can be a vapor compression refrigeration unit using a refrigerant such as a hydrofluorocarbon or hydrochlorofluorocarbon refrigerant. More specifically, the liquid cooling unit  116  can use an environmentally-safe refrigerant. In some embodiments, the liquid cooling unit  116  can be a water chiller comprising a titanium evaporator. 
     The liquid cooling unit  116  can be configured to ensure that the nutrient solution  112  delivered to the grow columns  102  (whether new instances of the nutrient solution  112  or the recaptured nutrient solution  112 ) is cooled to between about 65 degrees to about 68 degrees Fahrenheit (about 18 degrees to about 20 degrees Celsius). The system  100  can comprise multiple liquid cooling units  116  used to cool the nutrient solution  112 . 
     The nutrient solution  112  within the nutrient reservoir  110  can also be aerated or oxygenated by an aerator or oxygenation unit. The aerator or oxygenation unit can ensure that the nutrient solution  112  within the nutrient reservoir  110  is oxygenated prior to reaching the grow columns  102 . 
       FIG. 2B  illustrates an embodiment of a capture reservoir  130  comprising a submersible filter  134 . The capture reservoir  130  can be a tank or container made in part of a non-corrosive or inert material. For example, the capture reservoir  130  can be a tank or container made in part of high-density polyethylene (HDPE), such as food-grade HDPE. 
     The capture reservoir  130  configured to collect the captured or recaptured nutrient solution. The capture reservoir  130  can be in fluid communication or fluidly coupled to one or more capture conduits  128 . The capture conduits  128  can be pipes, tubes, or other types of conduits carrying the captured or recaptured nutrient solution to the capture reservoir  130 . 
     The capture reservoir  130  can have a capture reservoir volume. For example, the capture reservoir volume can be between about 10 gallons (38 L) to about 50 gallons (189 L). More specifically, the capture reservoir volume can be about 15 gallons (57 L) or about 30 gallons (114 L). 
     In some embodiments, the capture reservoir volume can be less than the nutrient reservoir volume. One unexpected result discovered by the applicants is that a capture reservoir having a capture reservoir volume less than a nutrient reservoir volume improved the quality of the nutrient solution  112  eventually delivered to the grow columns  102 . The difference in volumes between the two reservoirs ensures that, for the most part, a smaller amount of the captured or recaptured nutrient solution is introduced to a larger amount of the nutrient solution  112  within the nutrient reservoir  110  rather than a larger amount of the captured or recaptured nutrient solution added to a smaller amount of the nutrient solution  112  within the nutrient reservoir  110 . This reduces the strain on the liquid cooling unit  116  and ensures that the nutrient solution  112  eventually delivered to the grow columns  102  is the correct temperature and sufficiently oxygenated or aerated. 
     The capture reservoir  130  can comprise at least one reservoir inlet  132 . In some embodiments, the reservoir inlet  132  can be a distal segment of one of the capture conduits  128 . In other embodiments, the reservoir inlet  132  can be an inlet affixed within the capture reservoir  130 . The reservoir inlet  132  can be covered by a submersible filter  134 . The submersible filter  134  can be submerged in the captured or recaptured nutrient solution within the capture reservoir  130 . 
     The submersible filter  134  can be configured to capture and filter out particulates from the captured or recaptured nutrient solution. For example, the submersible filter  134  can capture and filter out plant debris, insects, or other waste products within the captured or recaptured nutrient solution. The submersible filter  134  can be cleaned or replaced on a periodic or regular basis to ensure the submersible filter  134  can continue to capture and filter out debris and other waste products. 
     The submersible filter  134  can be tied, clasped, or clamped around the reservoir inlet  132  such that fluid flowing through the reservoir inlet  132  passes through the submersible filter  134  before reaching the inside of the capture reservoir  130   
     In some embodiments, the submersible filter  134  can be a free-floating filter bag tied, clasped, or clamped around the reservoir inlet  132 . For example, the submersible filter  134  can be made in part of nylon or be a nylon mesh bag having fine pores, holes or perforations. The submersible filter bag can be detached from the reservoir inlet  132  to be emptied and cleaned. One unexpected discovery made by the applicants is that a free-floating submersible filter such as a free-floating filter bag tied around the reservoir inlet improved the filtering capabilities of the capture reservoir  130 . 
     In other embodiments, the submersible filter  134  can be a filter cage or box-type filter structure. In these embodiments, the entire filter cage or box-type filter structure can be detached from the reservoir inlet  132  and emptied or cleaned. 
     Although  FIG. 2B  illustrates one instance of the submersible filter  134 , it is contemplated by this disclosure that a plurality of submersible filters  134  can be used to capture and filter out particulates from the captured or recaptured nutrient solution. 
     The capture reservoir  130  can also comprise or be coupled to one or more pumps  136  (not shown in  FIG. 2B ). In some embodiments, the one or more pumps  136  can be submersible water pumps. In other embodiments, the one or more pumps  136  can be centrifugal water pumps or impeller-type pumps. The one or more pumps  136  can pump the captured or recaptured nutrient solution from the capture reservoir  130  to the nutrient reservoir  110  to be cooled by the cooling unit  116 , aerated, and eventually recirculated back to the grow columns  102 . 
     The system  100  disclosed herein comprising the nutrient reservoir  110  and the capture reservoir  130  can reuse up to 95% to 98% of water flowing through the system  100 . In this manner, water costs can be reduced up to 90% compared to traditional indoor hydroponic grow environments. 
       FIG. 3  illustrates a plurality of grow columns  102  comprising angled housings  106 . As previously discussed, the grow columns  102  can be made in part of a polymeric material or another type of corrosion-resistant material. For example, the grow columns  102  can be made in part of PVC pipes having a pipe diameter of between about 3 inches (76 mm) to about 4 inches (102 mm). In other embodiments, the pipe diameter can be 5 inches (127 mm) or greater. More specifically, the PVC pipes can be Schedule 40 PVC pipes. Alternatively, the PVC pipes can be Schedule 80 PVC pipes. 
     The grow columns  102  can each be made in part of a plurality of detachable column segments  300  connected by column couplers  302 . At least one angled housing  106  can be coupled to each of the detachable column segments  300 . In embodiments where the angled housings  106  are Wye fittings or Wye pipe fittings (for example, as shown in  FIG. 3 ), some of the detachable column segment  300  can be coupled to two angled housings  106 . In these embodiments, at least part of each angled housing  106  can serve as segments of the grow column  102 . 
     In other embodiments not shown in the figures but contemplated by this disclosure, each of the detachable column segments  300  can be coupled to three or more angled housings  106  (for example, when the angled housings  106  are inserted into holes or openings defined along the column segment  300 ). 
     In some embodiments, the column couplers  302  can be expandable pipe joints. For example, the column couplers  302  can be made in part of elastomeric PVC. The column couplers  302  can be flexible and expandable such that the coupler accommodates any expansion or contraction of the detachable column segments  300 . More specifically, the column couplers  302  can be Fernco® expandable joints or couplers. 
     The column couplers  302  can be secured to the detachable column segments  300  or a portion of the angled housings  106  using one or more hose clamps or other types of pipe clamps. For example, the hose clamps can be screw-tightened clamps made in part of stainless steel. 
     Each of the angled housings  106  can comprise a housing lumen  108  in fluid communication with a column lumen  104 . The angled housings  106  can be configured to accommodate plant matter (see, e.g.,  FIG. 7 ). In some embodiments, each of the angled housings  106  can be configured to accommodate a plantlet such as a young  Cannabis  clone. The housing lumen  108  can allow the roots of the plant or plantlet to grow further into the housing lumen  108  and, eventually, into the column lumen  104 . The roots of the plant can grow further into the column lumen  104  and become intertwined or entangled with roots of other plants in other angled housings  106  along the same grow column  102 . This can allow the roots to form a root column  800  as shown in  FIG. 8 . 
     The grow columns  102  can be disassembled by separating the detachable column segments  300  from one another. Moreover, the grow columns  102  can also be disassembled by separating the angled housings  106  from one another or from the detachable column segments  300 . 
     In some embodiments, the root column  800  can be extracted from the column lumen  104  when the grow column  102  is disassembled. In these embodiments, the system  100  and methods (e.g., method  900 ) disclosed herein can be considered systems and methods for cultivating a root column. 
       FIG. 3  also illustrates that the grow columns  102  can be coupled to one or more capture conduits  128 . The capture conduits  128  can have capture lumens in fluid communication with the column lumens  104 . The capture conduits  128  can be configured to capture (and eventually, recapture) nutrient solution  112  flowing through the column lumens  104 . In some embodiments, the capture conduits  128  can be positioned vertically below the grow columns  102  and rely on gravity to direct the nutrient solution  112  to the capture conduits  128 . In other embodiments, the capture conduits  128  can be coupled to segments of the grow column  102  along the length of the grow column  102  such that excess nutrient solution  112  or unused nutrient solution  112  flows out of the column lumens  104  into the capture conduits  128 . 
     In some embodiments, the capture conduits  128  can be PVC pipes having a pipe diameter slightly larger than the diameter of the grow columns  102  (e.g., about 4 inches or 5 inches). In these and other embodiments, the capture conduits  128  can be made in part of multiple segments of PVC pipes coupled by couplers such as the column couplers  302  previously discussed. 
     The grow columns  102  and the capture conduits  128  can be disassembled in order to allow a user or grower to clean and maintain the grow columns  102  and the capture conduits  128 . One advantage of the system  100  disclosed herein is that one or more grow columns  102  or portions of such grow columns  102  can be disassembled for cleaning or maintenance without affecting the other grow columns  102  or the remainder of the system  100 . This can also allow a user or grower to easily swap out one or more grow columns  102  or replace segments of grow columns  102  when issues are discovered with the plants or plantlets cultivated in such grow columns  102 . 
     In some embodiments, the grow columns  102  can be attached or otherwise secured or affixed to a wall of an indoor grow environment. For example, the grow columns  102  can be coupled to pipes, structures, columns, or supports along one or more walls of the indoor grow environment. The grow columns  102  can be coupled via braces, bands, or other types of mechanical fasteners or securement mechanisms. 
     For example, the grow columns  102  can cover four walls of a room or indoor grow environment. More specifically, the grow columns  102  can cover rectangular walls of a room comprising four walls and corners. In these embodiments, the grow columns  102  can be arranged substantially in a cuboid formation (i.e., where a top down view of such a formation would look like a rectangle made up of a plurality of circles lined up next to one another). 
     In other embodiments, the grow columns  102  can be arranged substantially in a cylindrical formation or cover the walls of an indoor space shaped substantially as a cylinder (i.e., where a top down view of such a formation would look like a larger circle made up of a plurality of smaller circles serving as the circumference of the larger circle). 
     In alternative embodiments, the grow columns  102  can be arranged substantially in an ovoid or ellipsoid configuration. In further embodiments, the grow columns  102  can be curved to accommodate the curvature of walls of a dome-shaped indoor environment. 
     In other embodiments not shown in the figures but contemplated by this disclosure, the grow columns  102  can be free-standing columns coupled to positions along the ceiling and floor of an indoor space. In further embodiments contemplated by this disclosure, the grow columns  102  can be coupled to a moveable platform or frame. 
     In all such embodiments, the grow columns  102  can surround one or more omnidirectional light towers  138 . The one or more omnidirectional light towers  138  can be positioned substantially in a center of the grow columns  102  or substantially equidistant from the grow columns  102 . 
     Where the grow columns  102  are free-standing or not attached or secured to walls of an indoor grow environment, the free-standing grow columns  102  can surround one or more omnidirectional light towers  138 . When the grow columns  102  are coupled or otherwise secured to a moveable platform, the one or more omnidirectional light towers  138  can also be coupled or secured to the moveable platform. 
       FIG. 4A  illustrates a close-up view of an angled housing  106  comprising a basket  400  or planter basket positioned within the housing lumen  108  of the angled housing  106 . In certain embodiments, the angled housings  106  can be positioned at an angle with respect to a longitudinal axis of the grow column  102 . This angle can be about 45 degrees with respect to the longitudinal axis of the grow column  102 . In other embodiments, the angle can be between about 25 degrees to about 45 degrees (e.g., about 30 degrees). In further embodiments, the angle can be between about 45 degrees and 60 degrees. 
     As previously discussed, the angled housings  106  can be 3-inch PVC Wye fittings coupled to 3-inch Schedule 40 PVC pipes serving as segments of a grow column  102 . In other embodiments not shown in the figures but contemplated by this disclosure, the angled housings  106  can be pipes or other types of containers inserted into openings, cavities, or perforations defined along the sides of the grow columns  102 . In these embodiments, the pipes or containers can be inserted at an angle relative to a longitudinal axis of the grow column  102 . 
       FIG. 4B  illustrates an embodiment of a basket  400  or planter basket configured to be placed within the angled housing  106 . In some embodiments, the basket  400  can be made of a polymeric material such as a corrosion-resistant plastic. For example, the basket  400  can be made in part of polypropylene. As a more specific example, the basket  400  can be a 3-inch or 2-inch net pot or planter cup. 
     The basket  400  can have a number of perforations  402  defined along the bottom, sides, or both the bottom and sides of the basket  400 . The basket  400  can be configured to hold plant matter, growing medium, or a combination thereof. The perforations  402  along the bottom, sides, or bottom and sides of the basket  400  can allow the roots of the plant or plantlet to grow through the sides or bottom of the basket  400  and further into the housing lumen  108  or the column lumen  104 . 
     In some embodiments, the basket  400  can be tapered or shaped substantially as a frustoconic having perforations  402  along the bottom and sides of the frustoconic. The basket  400  can fit into the housing lumen  108  via an interference fit. In certain embodiments, the basket  400  can have a flanged portion or rim around the top of the basket  400  that extend out radially such that the flanged portion or rim rests against ledges or indentations within the housing lumen  108 . 
     The basket  400  can be partially filled with a growing medium. In some embodiments, the growing medium can comprise coco coir (or the fibrous material of the coconut), peat moss (sphagnum moss), coco coir peat, or a combination thereof. 
       FIG. 4C  illustrates an angled housing  106  comprising a light-blocking collar  404  and a plantlet extending through a port  406  along the light-blocking collar  404 . The light-blocking collar  404  can be configured to block or obstruct light from entering the housing lumen  108  when a plant or plantlet is planted or housed partly within the angled housing  106 . 
     In some embodiments, plantlets or young plants measuring about eight inches or less can be introduced into the angled housings  106 . For example, the plantlets can be  Cannabis  clones measuring about eight inches or less. In other embodiments, the plantlets or young plants can be introduced into the angled housings  106  when their roots are between three inches to four inches in length. In one example embodiment, a basket  400  can be first positioned within the housing lumen  108  and a growing medium can be introduced into the basket  400 . The plant or plantlet can then be transplanted into the growing medium within the basket  400 . The plant or plantlet can also be transplanted first into the basket  400  and additional growing medium can be added to the basket  400 . The light-blocking collar  404  can then be positioned at the mouth or entrance of the angled housing  106  or close to the mouth or entrance of the angled housing  106 . 
     The light-blocking collar  404  can have a port  406  or opening configured to allow at least part of the plant or plantlet to extend through the port  406 . The light-blocking collar  404  can also have a slit or slot extending radially such that the light-blocking collar  404  can be opened or deformed to allow the collar to surround the stem or stalk of the plant or plantlet. 
     In some embodiments, the light-blocking collar  404  can be made in part of a water-resistant synthetic rubber such as polychloroprene (e.g., Neoprene®) or an elastomeric polymer such as ethylene-vinyl acetate. The light-blocking collar  404  can also be darkly-colored or opaque. For example, the light-blocking collar  404  can be a black-colored Neoprene® disk configured to fit tightly within at least part of the housing lumen  108 . 
     The light-blocking collar  404  can be used to support or hold the stem or stalk of the plant. In certain embodiments, the light-blocking collar  404  can be used in lieu of the basket  400  (especially when the plants have surpassed a certain size threshold). 
       FIG. 4D  illustrates an angled housing  106  comprising a porous reticulated foam support  408  for supporting plant matter. In some embodiments, the reticulated foam support  408  can be used in lieu of the light-blocking collar  404 , the basket  400 , or a combination thereof. 
     The porous reticulated foam support  408  can occupy at least part of the housing lumen  108  and can be defined by a cavity or channel configured to accommodate plant matter. At least part of the porous reticulated foam support  408  can extend out past the angled housing  106 . 
     The porous reticulated foam support  408  can have an open-cell structure comprising a multitude of pores. In some embodiments, the porous reticulated foam support  408  can have a pore density of between about 10 pores per inch (PPI) to about 35 PPI. The walls of the porous reticulated foam support  408  can be made of interconnected or interlocking struts or strands. The empty space in between such struts or strands can take up 95% to 98% of the overall volume occupied by the foam support  408 . 
     In some embodiments, the porous reticulated foam support  408  can be made in part of polyurethane, polyether, polyesters or polyester glycol, or a combination thereof. In these and other embodiments, the porous reticulated foam support  408  can also be made of an organic material or organic fibers. 
     As shown in  FIG. 4D , the porous reticulated foam support  408  can be shaped substantially as a porous tube having a hollow cavity extending through the length of the porous tube. The open-cell structure of the foam support  408  can allow the foam support  408  to act as a sponge to hold water or nutrient solution  112  while the struts or strands of the foam support  408  can block light and act as a filter or protective barrier against contaminants entering the angled housings  106 . 
       FIG. 5  illustrates a plurality of grow columns  102  surrounding an embodiment of an omnidirectional light tower  138  comprising an activated-carbon air filter  146  serving as a base of the omnidirectional light tower  138 . The omnidirectional light tower  138  can be configured to shine light on the foliage or other chlorophyll containing portions of the plants or plantlets extending from the angled housings  106 . As previously discussed, the grow columns  102  and the angled housings  106  can be positioned such that the foliage or other chlorophyll containing portions of the plants or plantlets housed by the angled housings  106  extend or face the lamps of the omnidirectional light tower  138 . 
     The omnidirectional light tower  138  can comprise a columnar housing  140  extending vertically upward toward a ceiling of the indoor grow environment. At least part of the columnar housing  140  can be made of a transparent glass-type material. For example, the transparent segments of the columnar housing  140  can be made in part of fused quartz or borosilicate glass (e.g., Pyrex® glass). In some embodiments, the transparent segments of the columnar housing  140  can be a quartz column substantially shaped as a cylinder or tube. The transparent segments of the columnar housing  140  can comprise a number of high-intensity discharge (HID) lamps arranged in a stacked or vertically-aligned manner. 
     The omnidirectional light tower  138  can comprise at least two types of HID lamps. In some embodiments, the two types of HID lamps can comprise high-pressure sodium (HPS) lamps  142  and dual arc hybrid lamps  144 . 
     In certain embodiments, the dual arc hybrid lamp  144  can be a combination HPS and metal halide (MH) lamp. In other embodiments, the dual arc hybrid lamp  144  can be a combination HPS and ceramic metal halide (CMH) lamp. 
     In some embodiments, the omnidirectional light tower  138  can comprise seven HID lamps arranged in a stacked or vertically-aligned manner. For example, the omnidirectional light tower  138  can comprise four HPS lamps  142  and three dual arc hybrid lamps  144 . In other example embodiments, the omnidirectional light tower  138  can comprise three HPS lamps  142  and four dual arc hybrid lamps  144 . 
     In further embodiments not shown in the figures but contemplated by this disclosure, the omnidirectional light tower  138  can comprise between five and seven HID lamps or greater than seven HID lamps depending on the height of the indoor growing environment. 
     In some embodiments, the HPS lamps  142  can be 1000 watt (W) lamps capable of outputting between about 90,000 to about 140,000 lumens and have a temperature rating of between about 2000 degrees Kelvin to about 3800 degrees Kelvin. The HPS lamps  142  can emit light primarily having an orange or red hue or tint where the spectral range is focused between about 560 nanometers (nm) to about 700 nm. The use of HPS lamps  142  can benefit plants in their initial vegetative phase or stage. 
     In these and other embodiments, the dual arc hybrid lamps  144  can be hybrid lamps comprising a 400 W metal halide or ceramic metal halide arc tube and a 600 W high pressure sodium arc tube. The dual arc hybrid lamps  144  can be capable of outputting between about 110,000 to about 150,000 lumens and have a temperature rating of between about 3000 degrees Kelvin to about 4200 degrees Kelvin. The dual arc hybrid lamps  144  can emit light primarily having a blue or blue-green hue or tint where the spectral range is focused between about 400 nm to 540 nm. The use of dual arc hybrid lamps  144  can benefit plants in their later flowering and fruiting stages. 
     The two types of HID lamps can be arranged in an alternating stacked arrangement so that all plants or plantlets housed within angled housings  106  along the entire height of the grow columns  102  can be exposed to the light emitted by such lamps. In this manner, plants or plantlets at the very bottom (or very top) of the grow columns  102  are not positioned at a disadvantage from other plants or plantlets along the remainder of the grow columns  102 . This sets the omnidirectional light tower  138  apart from traditional hydroponic lighting systems which are either hung from the ceilings so that such lights favor plants near the top of the growing environment or placed on the ground such that they favor plants near the bottom of the growing environment. 
     The transparent segments of the columnar housing  140  and the stacked or vertically-aligned arrangement of the lamps can allow the light tower  138  to emit light in all directions (i.e., in an omnidirectional manner). A technical advantage of this light design over other hydroponic lighting systems is that this light design reduces the need for cumbersome light reflectors or hoods and drastically reduces the number of high-powered lamps needed to support a high-density growing environment. For example, the applicants have discovered that a version of the omnidirectional light tower  138  disclosed herein comprising only seven HID lamps can support a total of 500  Cannabis  clones throughout the plants&#39; entire life cycle including from the initial vegetative stage to the later flowering stage. 
     Moreover, it has been discovered by the applicants that using both HPS lamps  142  and dual arc hybrid lamps  144  comprising both HPS arc tubes and metal halide arc tubes significantly accelerated the growth of plants and plantlets within the angled housings  106 . 
       FIG. 5  also illustrates that the transparent segments of the columnar housing  140  (e.g., the quartz columns or tubes) containing the lamps of the omnidirectional light tower  138  can be connected to one another by one or more flexible ducts  500  or connectors. In some embodiments, the flexible ducts  500  or connectors can be aluminum foil ducts, semi-rigid metal ducts, or reinforced plastic ducts. The flexible ducts  500  and the transparent segments of the columnar housing  140  can form most of the columnar housing  140 . 
     The columnar housing  140  can define a housing space  502  extending through the entirety of the interior of the columnar housing  140 . The housing space  502  can include the interior or inner lumens of the quartz columns and the flexible ducts  500 . The HID lamps, including the HPS lamps  142  and the dual arc hybrid lamps  144 , can be housed within the housing space  502 . 
     In addition,  FIG. 5  illustrates that the omnidirectional light tower  138  can comprise an activated-carbon air filter  146  serving as a base of the omnidirectional light tower  138 . The activated-carbon air filter  146  can comprise a filter housing  148  surrounding a filter cavity comprising activated carbon. In some embodiments, the activated-carbon air filter  146  can also have a cloth filter or mesh filter covering the outer filter surface of the filter housing  148 . 
     The activated-carbon air filter  146  can be configured to filter air that is drawn into the filter cavity. The filter cavity can be in fluid communication with the housing space  502  within the columnar housing  140 . 
     In some embodiments, the activated carbon within the filter cavity can be made in part from coconut shells. The cloth filter or mesh can act as an extra filtering layer and can prevent the activated carbon from becoming contaminated or prevent the activated carbon from leaking out and going to waste. The cloth filter or mesh can be detached from the filter housing  148  for cleaning and maintenance. The cloth filter can also be replaced on a regular basis. 
       FIG. 6  illustrates the top of the omnidirectional light tower  138  comprising an inline duct fan  150  coupled to the top of the columnar housing  140 . The inline duct fan  150  can be part of the omnidirectional light tower  138 . The inline duct fan  150  can be positioned above the HID lamps. 
     In some embodiments, the inline duct fan  150  can be an inline duct fan capable of supporting airflow rates of between about 1480 cubic feet per minute (CFM) to about 1800 CFM. The inline duct fan  150  can be remotely controlled and can comprise a programmable controller. 
     The inline duct fan  150  can be configured to cool the omnidirectional light tower  138  and, ultimately, the indoor grow environment. In addition, the inline duct fan  150  can periodically or continuously draw in air from the indoor grow environment into the activated-carbon air filter  146  to filter or purify the air within the indoor grow environment. 
     The inline duct fan  150  can draw in air through the filter housing  148  of the activated-carbon air filter  146  at the bottom of the omnidirectional light tower  138 . As previously discussed, the filter cavity can comprise activated carbon (e.g., activated carbon from coconut shell). The air can flow into the filter cavity, then be drawn up through the housing space  502 , and then be expelled by the inline duct fan  150  into air ducts or vents leading to an environment outside the indoor grow environment. This can simultaneously remove heat generated by the various lamps within the columnar housing  140  (by expelling the heated air into an external environment outside the indoor grow environment) and ventilate the indoor grow environment. 
     In this manner, the omnidirectional light tower  138  can serve multiple purposes including providing light to plant matter within the high-density indoor grow environment, removing heat generated by the lights, and filtering or purifying the air within the indoor grow environment. 
     The system  100  can also comprise additional air cooling units or air conditioning units to supply filtered cool air into the indoor grow environment. The presence of an omnidirectional light tower  138  having its own heat removal mechanism reduces the reliance of the indoor grow environment on energy inefficient air conditioning units or cooling units. This greatly reduces energy costs and equipment maintenance costs. 
     As shown in  FIGS. 5 and 6 , the omnidirectional light tower  138  can be portable and moveable. For example, the activated-carbon air filter  146  serving as the base of the light tower  138  can have casters or wheels coupled to the bottom of the air filter  146 . 
     Moreover, the omnidirectional light tower  138  can also be rotatable (rotate with respect to its longitudinal axis) or capable of being moved along a track or rails within the indoor grow environment. 
     One technical problem faced by the applicants is how to adequately supply light to all plants within a high-density indoor grow environment without inundating the indoor grow environment with too many heat-generating lamps. In addition, the heat generated by traditional grow lamps must often be countered with expensive and bulky air conditioning units that drive up energy costs and equipment maintenance costs. The technical solution discovered by the applicants is the omnidirectional light tower  138  disclosed herein comprising different types of lamps arranged in an alternating stacked arrangement comprising an air filter serving as a base of the light tower  138  and an inline fan at the top of the light tower  138  drawing in air through the air filter into the tower housing and out to an external environment away from the indoor grow environment. 
       FIG. 7  is a black-and-white image of plants growing out of the angled housings  106  of a plurality of grow columns  102 . As shown in  FIG. 7 , the grow columns  102  can be affixed or otherwise secured to a wall of an indoor space such as a warehouse or room. In these embodiments, the grow columns  102  can cover all of the walls of the indoor space. In other embodiments not shown in the figures but contemplated by this disclosure, the grow columns  102  can be free-standing columns coupled to positions along the ceiling and floor of an indoor space. In further embodiments contemplated by this disclosure, the grow columns  102  can be coupled to a moveable platform or frame. 
     In certain embodiments, the system  100  can cultivate up to 500 plants within a 100 square feet (or about 9.29 square meters) indoor space or facility. The system  100  can use an omnidirectional light tower  138  comprising seven HID lamps (a combination of HPS lamps  142  and hybrid lamps  144 ) to cultivate the 500 plants. In other embodiments, the indoor space or facility can be more than 100 square feet (e.g., 400 square feet) and the indoor space or facility can be divided into four 100 square feet spaces with each 100 square feet space having an omnidirectional light tower  138  in the middle surrounded by grow columns  102  on all sides. In these embodiments, the system  100  can cultivate up to 2000 plants within the 400 square feet space using four omnidirectional light towers  138 . 
     In other embodiments, the system  100  can cultivate up to 1000 plants within a 100 square feet space or facility by positioning the grow columns  102  closer to one another. 
       FIG. 8  is a black-and-white image of a root column  800  extracted from a column lumen  104  of a grow column  102 . The root column  800  can be harvested by separating the plurality of detachable column segments  300  and removing the intact root column  800  from the column lumen  104 . The root column  800  can be formed from the roots of  Cannabis  plants grown within the angled housings  106  of one of the grow columns  102  disclosed herein. 
     As previously discussed, the housing lumens  108  of the angled housings  106  can allow the roots of plants or plantlets (e.g.,  Cannabis  clones) to grow through the housing lumens  108  and into the column lumen  104  in fluid communication with the housing lumens  108 . Once the roots of the plants or plantlets grow into the column lumen  104 , the roots become intertwined or entangled with roots of other plants in other angled housings  106  along the same grow column  102 . 
     Over time, the roots become more intertwined and entangled and form into a root column  800 . Once the plants within the angled housings  106  are harvested, the root column  800  can also be harvested by disassembling the detachable column segments  300  making up the grow column  102 . In this manner, the system  100  and methods (e.g., method  900 ) disclosed herein can also be considered systems and methods for cultivating a root column, for example, a  Cannabis  root column. 
     Once harvested, the root column  800  can be used to make medicinal teas, salves, and medicinal preparations. For example, the root column  800  can be dried and ground up into a powder for making salves or topicals. The root column  800  can also be cut up and boiled to make certain medicinal teas or brewed drinks. The root column  800  can be cut up to be used as a growing medium for future plants or for composting purposes. Moreover, the root column  800  can also be ground up and used as mulch or to replenish soil. 
     One unexpected result discovered by the applicants is that the system and methods disclosed herein can also be used to cultivate high-quality root columns that can be sold for their medicinal properties. Such robust and compact root columns are not formed in traditional hydroponic systems relying on horizontal watering troughs or conduits. 
       FIG. 9  is an embodiment of a method  900  of cultivating plants without soil. The method  900  can be undertaken using the entire system  100  disclosed herein or parts thereof. 
     In some embodiments, certain steps of the method  900  can also be used to cultivate  Cannabis  clones. In other embodiments, certain steps of the method  900  can also be used to cultivate, inter alia, beets, tomatoes, eggplants, lettuce, kale, basil and other herbs, strawberries, blueberries, cucumbers, pumpkins, or watermelons. 
     The method  900  can comprise providing one or more grow columns  102  in step  902 . Each of the one or more grow columns  102  can comprise a column lumen  104  and one or more angled housings  106  coupled to the grow column  102 . 
     The method  900  can also comprise providing an omnidirectional light tower  138  in step  904 . The omnidirectional light tower  138  can comprise a columnar housing  140 , one or more high-pressure sodium lamps  142  positioned within transparent segments of the columnar housing  140  and at least one dual arc hybrid lamp  144  positioned above or below the one or more high-pressure sodium lamps  142  within the columnar housing  140 . 
     The method  900  can further comprise positioning the one or more grow columns  102  and the one or more angled housings  106  such that the angled housings  106  extend toward the omnidirectional light tower  138  in step  906 . Each of the angled housings  106  can comprise a housing lumen  108  in fluid communication with the column lumen  104 . Each of the angled housings  106  can be configured to accommodate plant matter. The housing lumen  108 , the column lumen  104 , or a combination thereof can be configured to accommodate root growth of the plant matter into such lumens. 
     The method  900  can also comprise delivering a nutrient solution from a nutrient reservoir  110  to the one or more grow columns  102  in step  908 . The nutrient solution can be delivered via one or more fluid delivery pipes  118  in fluid communication with the nutrient reservoir  110 . In some embodiments, one or more segments of the fluid delivery pipes  118  can be positioned above the column lumens  104  of the grow columns  102 . Step  908  can further comprise spraying the nutrient solution flowing through the fluid delivery pipes  118  into the column lumens  104  using spray sprinklers  122  coupled to the fluid delivery pipes  118  positioned above the column lumens  104 . The nutrient solution can be sprayed into the column lumens  104  periodically such that spray periods are followed by dry periods where no nutrient solution is delivered into the column lumens  104 . 
     The method  900  can also comprise capturing (and recapturing) nutrient solution flowing through the one or more grow columns  102  in step  910 . The nutrient solution can be captured (and recaptured) using one or more capture conduits  128 . The capture conduits  128  can direct or otherwise carry the captured (or recaptured) nutrient solution flowing through the column lumens  104  to a capture reservoir  130 . The captured or recaptured nutrient solution can be filtered by one or more submersible filters  134  within the capture reservoir  130 . 
     The method  900  can further comprise delivering the nutrient solution captured or recaptured to the nutrient reservoir  110  to be recirculated and reused in step  912 . The nutrient solution can be pumped from the capture reservoir  130  to the nutrient reservoir  110 . The nutrient solution can be cooled or chilled to between about 65 degrees to about 68 degrees Fahrenheit using a liquid cooling unit  116 . The nutrient solution can be cooled by being circulated through the liquid cooling unit  116 . The nutrient solution can be cooled or chilled prior to being delivered or recirculated to the one or more grow columns  102 . 
     The method  900  can also comprise cooling the omnidirectional light tower  138  by drawing in air through an activated-carbon air filter  146  serving as a base of the omnidirectional light tower  138  in step  914 . The air can be drawn into the activated-carbon air filter  146  by an inline duct fan  150  positioned above the HPS lamps  142  and dual arc hybrid lamps  144  within the columnar housing  140 . The activated-carbon air filter  146  can comprise a filter cavity comprising activated carbon. The filter cavity can be in fluid communication with a housing space within the columnar housing  140 . The HPS lamps  142  and the dual arc hybrid lamps  144  can be contained within the housing space of the columnar housing  140 . The inline duct fan  150  can draw in air through the activated-carbon air filter  146  into the filter cavity, then up through the housing space  502 , and then be expelled by air ducts to an environment outside the indoor grow environment. This can ventilate the indoor grow environment and remove heat generated by the lamps. 
     In other embodiments, the method  900  disclosed herein can also be part of a method for cultivating a root column (such as the root column  800  shown in  FIG. 8 ). As previously discussed, the root column can be harvested by separating the plurality of detachable column segments  300  and removing the root column from the column lumen  104 . The root column can be a  Cannabis sativa  root column,  Cannabis indica  root column, or a root column of hybrids thereof. 
     The method  900  can comprise additional steps not shown in  FIG. 9 . For example, the method  900  can further comprise steps or operations described in the preceding portions of this disclosure. 
     A number of embodiments have been described. Nevertheless, it will be understood by one of ordinary skill in the art that various changes and modifications can be made to this disclosure without departing from the spirit and scope of the embodiments. Elements of systems, devices, apparatus, and methods shown with any embodiment are exemplary for the specific embodiment and can be used in combination or otherwise on other embodiments within this disclosure. For example, the steps of any methods depicted in the figures or described in this disclosure do not require the particular order or sequential order shown or described to achieve the desired results. In addition, other steps operations may be provided, or steps or operations may be eliminated or omitted from the described methods or processes to achieve the desired results. Moreover, any components or parts of any apparatus or systems described in this disclosure or depicted in the figures may be removed, eliminated, or omitted to achieve the desired results. In addition, certain components or parts of the systems, devices, or apparatus shown or described herein have been omitted for the sake of succinctness and clarity. 
     Accordingly, other embodiments are within the scope of the following claims and the specification and/or drawings may be regarded in an illustrative rather than a restrictive sense. 
     Each of the individual variations or embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other variations or embodiments. Modifications may be made to adapt a particular situation, material, composition of matter, process, process act(s) or step(s) to the objective(s), spirit or scope of the present invention. 
     Furthermore, where a range of values is provided, every intervening value between the upper and lower limit of that range and any other stated or intervening value in that stated range is encompassed within the invention. Also, any optional feature of the inventive variations described may be set forth and claimed independently, or in combination with any one or more of the features described herein. 
     All existing subject matter mentioned herein (e.g., publications, patents, patent applications and hardware) is incorporated by reference herein in its entirety except insofar as the subject matter may conflict with that of the present invention (in which case what is present herein shall prevail). The referenced items are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such material by virtue of prior invention. 
     Reference to a singular item, includes the possibility that there are plural of the same items present. More specifically, as used herein and in the appended claims, the singular forms “a,” “an,” “said” and “the” include plural referents unless the context clearly dictates otherwise. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as “solely,” “only” and the like in connection with the recitation of claim elements, or use of a “negative” limitation. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.