Contamination, quality and yield, and costs: this is the current order of concern for large-scale cannabis producers. These concerns have recently driven the largest producers to build their future on hybrid greenhouses. The cannabis industryrevolves around consumer preferences and government regulations to bend to those preferences. Because cannabis is predominantly smoked, regulations tend to focus on potential lung contaminates and target almost all pesticides, microbials, heavy metals, and mycotoxins that may be found in a plant. The skill to grow under stringent state lab testing to protect consumers requires the right tools; and the hybrid greenhouse model links traditional greenhouse technology with indoor grow protections.
One of the biggest worries of a cannabis farmer is outside air contaminants and pests. There are no GMO cannabis plants capable of fighting off these crop killers, and the lack of pesticides means entire crops can be destroyed from common airborne elements. Unlike a traditional greenhouse that relies on outside air constantly moving through the facility, the newest hybrid greenhouses are closed loop airflow systems that virtually eliminate airborne molds and microbials. The construction of a hybrid greenhouse is much more air-tight, allowing the IPM to be concentrated in the air scrubbing and around the building perimeters rather than all over the structure. Air circulation is the more complex discussion these days, and designs are evolving around large air channels designed into the base, so heated/cool air originates around the root level and are easier to clean as part of the floor. From there, air flow planning is then divided into two more layers on top of the initial root level. Rotating and cleaning the air at the next two levels of air goes beyond common horizontal fans and have evolved to large carbon filtered air fans, sometimes vertical, moving the air, plus the addition of ozone, UV-C, and dehumidification filtering units to control microbes and environment.
Hybrid greenhouses have only started to break the old-school theory that indoor quality and yields are superior. The environment can be controlled in both indoor and hybrid greenhouses in almost the exact same way, but it is hard to argue that natural sunlight is a negative to plant quality. If temperature, pressure, humidity, and nutrients are equal, the addition of sunlight with assisted supplemental light can be the best combination for a plant’s full potential. Many hybrid greenhouses have been called indoors with glass roofs for this reason. And as LED lighting explores fuller spectrums of light, the ability to control sunlight and supplemental light together only adds another tool to the grower’s arsenal to achieve higher results. Additionally, as black-out sealing and technology has developed, total darkness is now easily achievable in a greenhouse and knocks out the last peg in indoor operations claim to be a superior style. Even as the world of cannabis embraces producing oils from more economical outdoor and normal greenhouse produce, since most contaminants are stripped away regardless, the hybrid greenhouse dominates for year-round growing cycles, more harvests, and cleaner extractable material with less work and less wear.
To be fair, there is a place for all styles of grow, but if done right, the up-front costs and operating costs of a hybrid greenhouse are less than an indoor facility. The newest hybrid greenhouses have over 20-foot sidewalls to increase airflow, and the costs of materials, which are primarily steel and glass or aluminum and polycarbonate, are less than constructing a warehouse of similar size, not to mention a different zoning designation from light industrial. Due to the three layers of airflow, cooling and heating options are different and more geared to air-cleaning and airflow, as opposed to simply cooling to counteract heat indoors. In addition to AC reductions, hybrid greenhouses mainly attribute savings to the use of natural sunlight, which will significantly reduce lighting energy needs. Integrated pest management also changes, as sunlight is a natural disinfectant and not friendly to most molds, reducing needs for treatment of the plants that could harm growth in various stages and reduce costs.
Investors and operators are increasingly exploring the up-front costs versus longer term benefits of hybrid greenhouse to have a more consistent crop with less operating costs. As the industry develops and growers learn how to grow in a more advanced environment using analytics common to our food industry, the hybrid greenhouse for cannabis could find its way to the top of the food chain for developing the best genetics in an industrial way.