Cannabis has been grown as an outdoor crop for thousands of years. During prohibition, it was literally forced underground as black market grow-ops wanted to keep their operations under the radar. This has led to many advancements in both technology and process to maximize harvests from indoor crops. The majority of Licensed Producers (LPs) under the medical system leveraged those advancements, but scaled them up to meet the needs of the opportunity in Canadian cannabis. The result being large warehouses full of grid-draining lighting requirements paired with corresponding cooling needs and, some might say, mediocre plants.
While seed genetics and harvesting methods play a significant role in shaping the quality of the plant, growing techniques are equally important to the final product. Let's take a look at the three principal production practices found in Canadian cannabis: outdoor, indoor, and Sungrown.
Growing Cannabis Outdoors
There aren’t any LPs growing outside at the moment, but Health Canada is currently processing 172 cannabis cultivation licence applications that include an outdoor area, though it’s not 100 percent clear whether that area would be for cultivation or processing.

Sustainability is a big positive argument for outdoor growing, as the environmental costs of indoor cannabis cultivation are a worthwhile concern. For example, as much as 3% of the State of California’s energy usage is attributed to indoor cannabis production. It’s not just the artificial lighting systems that drain energy -- the cooling systems that keep plants at the optimal temperature also use a massive amount of electricity. By using sunlight, cannabis can grow with up to 90% less electricity. Sustainable growing methods can dramatically reduce the environmental impact of growing cannabis, and harnessing the natural environment also brings economic benefits. Growers who opt for outdoor reap the benefits of much lower costs as sunlight, air, and rain are free -- so there’s not such a big energy bill to contend with every month.
Another natural advantage of outdoor growing is mother nature’s ecosystem of pest management and soil creation. Organic growing methods can be used to minimize environmental impact and, in the US, outdoor craft growers are using ‘living soil’ to grow cannabis in earth that is its own ecosystem of bacteria, microbes, and little critters like earthworms that break down nutrients so they can be absorbed by the plants.
Of course, these very same essential elements can work against farmers growing any agricultural product, as a bad year weather-wise could wipe out an entire harvest. Additionally, the plant’s life cycle is a lot longer when grown naturally outdoors, which means a lower annual yield for growers. Cannabis plants naturally flower in late summer into the fall, which makes outdoor growing a very seasonal activity. Outdoor growers also have to protect against threats such as cross-contamination from other agricultural crops nearby, limits on pesticide use, and increased security to protect the crop.
Why do Licensed Producers Grow Cannabis Indoors?
Traditionally, cannabis has been cultivated outdoors, and when American conscientious draft objectors moved north to the West Coast of Canada in the 1950s-70s, they settled in areas such the Fraser Valley, Vancouver Island, the Kootenays, and the Okanagan, which all proved to be ideal microclimates for cannabis growth. As police technology developed over the decades, more growers moved indoors to escape detection. Growers adapted to indoor conditions to create plants that thrived undercover and the legacy from this time is a plethora of cultivation techniques that are used as best practice today.
Growing indoors makes it easier to control the humidity, air-flow, irrigation and light cycles that are essential for plant health, but this, in turn, makes the process incredibly energy-intensive. Causing the plant to artificially enter flowering stage means that the potential annual yield is way higher than plants grown outdoors that are limited by the seasons. Growing indoors enables producers to ensure a clean environment free of bugs and mould, so it’s less likely that pesticides will need to be used.

Different mediums are used for indoor growing, from soil in pots, which gives plants the natural nutrients that can be found outdoors; to coco coir and hydroponics. Hydroponics is a part of hydroculture, the idea of growing plants without soil by exposing the roots to a mineral nutrient solution in a water solvent or holding them in an inert material such as coco coir. It can both produce higher yields than soil-grown plants and be a cheaper option for growers.
Coco coir is made from coconut husks and comes as peat, chips, or fibres. It’s popular as an indoor growing medium because it can be fed with nutrient water and the resulting fast delivery of nutrients to the roots ensures healthier harvests and higher yields. High water retention and plenty of room for the root system creates ideal conditions for cannabis plants. A neutral pH balance means that this has to be carefully managed, along with the correct nutrients to make coir a successful indoor growing medium.
Sungrown: The Future of Clean Cannabis

Hybrid, or greenhouse, growing is becoming a popular method of sustainably producing cannabis as it offers the best of both indoor and outdoor growing. Such as the natural elements of full-spectrum sunlight, which enhances the growth of the plants, but with the added control of adjusting humidity and irrigation to create the optimum conditions for growing. Some LPs have converted existing greenhouses into cannabis growing areas, so the growing conditions may be more suited to fruit rather than flower and more energy (in the form of lighting and ventilation) is needed to get an optimum result consistently.
All of Tantalus Lab’s sungrown cannabis is cultivated in our state-of-the-art greenhouse, SunLab¹, which is the first completely environmentally controlled greenhouse that has been engineered specifically for cannabis in Canada. The sun naturally provides full-spectrum light to nurture plants with ideal photosynthetic input and this allows us to reduce our electricity usage by up to 90%. Pure recaptured rainwater is collected, triple-filtered, and dripline-fed to every plant. Cooling the growing environment and preventing stagnant moisture, SunLab¹ active air filtration allows for maximum airflow and cycles its air every seven minutes, reducing the risk of pests and mould to enable the highest Quality Assurance standard on Earth, naturally.
