For both home and commercial growers alike, managing garden space while maximizing yields can be a difficult task. This is especially true in urban areas, where the demand for marijuana is high—but so are the costs associated with renting, buying or building indoor space for cannabis cultivation.
For decades, the indoor horticulture industry has looked for ways to best utilize indoor garden space to maximize yields. Whether it be the giant flower farms of Holland, the sprawling vegetable greenhouses of Canada or the massive indoor commercial cannabis operations in the United States, many indoor growers are using vertical grow formats, whose popularity has been on the rise over the past few years with a new demographic: home growers.
Vertical grow systems are typically not do-it-yourself or build-your-own systems. Rather, commercially available vertical systems are purchased from hydroponic shops or wholesale distributors and then modified to the grower’s specific needs and space. Just like typical horizontal or flatbed grow systems, vertical grow systems can be used with almost any type of indoor grow technique, from hydroponics and aeroponics to soilless-medium methods. The latter is the least likely example one might find, though, as the weight of soil mediums—as well as the sheer volume—can make for cumbersome maintenance, less flexibility and lower functionality (more on this in a bit).
In traditional vertical grow systems, lights are hung vertically, usually on chains, with the plants placed around them in a cylindrical arrangement from floor to ceiling. A primary benefit of this arrangement is a better utilization of light, both in terms of energy efficiency and light absorption, by the encompassing plant canopy. The removal of reflectors creates a direct path for light energy, or photons, from bulb to plants and eliminates the conversion of light into heat that occurs when photons bounce off reflectors or are otherwise absorbed elsewhere and not by the plants. Additionally, when the vertical string of lights in these systems is adequately cooled (either by air-cooling tubes, water jackets or AC units), the plant canopy can sit within inches of the lights, thereby increasing the energy delivered to the plants.
While most vertical grow systems utilize this cylindrical arrangement to take better advantage of light placement and full photon absorption, alternatives to grow cylinders are becoming more popular, especially in large-format grows. Vertical rack systems are frequently used as commercial indoor growers look for lightweight, stackable grow systems that can deliver water and nutrients to plants quickly and effectively. These vertical grow systems mimic smaller horizontal hydro systems that can be stacked one on top of another from floor to ceiling with the required lighting placed in between each stackable tray or plant bed. Additionally, some vertical grow manufacturers claim that larger, shared beds in rack systems allow for better root systems, leading to larger yields. However, while the extra root-zone space lends itself to more developed roots, it also means each plant must share its food and water—and potential pests and diseases—with the other plants in its bed.
Vertical grow systems work the same way horizontal systems do, as the principals of horticultural are constant. Rather, it is the logistics that change with the footprint of the system in the room. The smaller footprint, which can range in size from 6 to 8 feet in diameter for cylindrical units or can wrap around the room for wall units, allows for more garden space in a single room as all the area is utilized, from floor to ceiling.
This is why many of the original (as well as some current) vertical grow systems deploy a cylindrical shape, as this allows for several units to be placed in a single room. And because there is no space lost to overhead lighting, all the space from floor to ceiling is dedicated to plant canopy. In cylindrical systems such as the well-known Coliseum, plants are placed in netted pot containers held in place by plastic tiers, angled slightly downward toward the center light channel. Behind the tiers is a thick wall that can hold spray misters, foggers or irrigation tubes for drip lines. At the bottom of the system are larger reservoirs to catch the runoff, just like hydroponic table systems.
Other systems can be more of a hybrid between a cylindrical system and a wall system. Wall systems use either premade wall frames or the walls of a room to attach hanging grow systems. The EcoSystem, for example, uses a cylindrical plant arrangement with vertical lights down a center channel and doors that swing open to provide access to the grow chamber. However, instead of housing the system mechanics within its chamber walls, growers attach slabs of rockwool, hung vertically around the sides, to grow their plants. Spaghetti lines run directly to the medium, and the vertical chamber is run as a top-feed hydroponic system.
Other vertical grow systems abandon the cylindrical geometry altogether and use structural walls, stackable racks or premade elements such as metal-pole frames from which to hang vertical grow systems. These systems range from NFT (nutrient film technique) and top-feed hydro systems to root mister/aeroponic systems. Normally, wall systems utilize narrow trays or troughs hung in a square arrangement on three or four walls with lights hanging vertically down the center, the same as cylindrical grow systems. All of these systems, whether square or cylindrical in design, do better with hydroponics rather than with soil systems, and each utilizes standard reservoirs and pump systems to deliver water and nutrients to plant sites.
Aside from the physical characteristics that vertical grow systems share, they also utilize common grow theories and techniques. In almost every vertical grow system—and especially in cylindrical units—a “sea of green” (SOG) technique must be utilized.
SOG gardens comprise many smaller plants, rather than fewer larger plants. This style of growing was developed primarily for indoor and greenhouse growers who have less space to work with than outdoor farmers. In theory, having many smaller plants is a way to mitigate the smaller yields when not…