In or out? Is cannabis grown indoors better than weed grown outdoors?

More cannabis producers are looking to capitalize on outdoor growing, with products such as edibles and beverages, hopefully, being legalized later this year.

While there certainly continues to be room for debate, one developing view is that carefully grown indoor cannabis makes for some of the best premium dried flower, while large-scale outdoor grown cannabis may fit the bill for those not-yet available extraction products.

“They’re not dried flower, so you don’t need that premium looking bud,” Jeannette VanderMarel, co-CEO and director of 48North Cannabis Corp., says of the latter.

Indoor grants the most control over growing conditions with greenhouses somewhere in the middle (although they are enclosed spaces, they rely on natural sunlight and often have some exposure to the natural environment).

There are three primary methods of growing cannabis large scale—controlled indoor growing, greenhouses and commercial-scale outdoor growing, notes Allan Rewak, executive director of the Cannabis Council of Canada. Indoor grants the most control over growing conditions with greenhouses somewhere in the middle (although they are enclosed spaces, they rely on natural sunlight and often have some exposure to the natural environment), Rewak points out.

What are some benefits of growing cannabis outside?

48North was the first company to apply for an outdoor grow licence in Canada, and VanderMarel cites what she sees as several pros of growing outdoors—growers gain the ability to grow larger and quicker yields when the height and root growth of plants are not limited by greenhouse or indoor building facilities, which she suggests could help address the industry’s supply shortage. The most obvious benefits of growing outdoors, however, are the energy savings from growing in a natural environment such as the ability to use sunlight fully. In addition to being more energy-efficient, the carbon footprint of field growth is also much lower.

VanderMarel explains that plants produce terpenes, or the compounds in essential oils, to protect themselves from pests and pathogens. “Outdoors, [cannabis plants] tend to produce more as they are more exposed to the elements,” she notes. Terpenes can also better enhance the medicinal effects of cannabis.

Outdoors, “there is a lesser degree of control and rising risk of external factors, whether that is microbacterial stuff in the soil, etc., it’s a little harder to control quality.”

Of course, outdoor growing is not without challenges, especially because the growing season is limited by Canadian winters. “You might be able to get one or maybe two crops if you’re lucky, whereas you can get three to four in a normal year from a greenhouse on a large scale,” Rewak says.

How does indoor cannabis growing stack up?

Indoor and greenhouse structures—as well as hybrid versions of these two—allow producers to grow year-round and reduce the risks of microbacteria and pests. Rewak points to the Aurora Cannabis Aurora Sky’s facility outside of the Edmonton International Airport, which is a hybrid indoor facility with a glass roof (for sunlight) that “is high-pressured to keep out particulate matter and dangerous microbes out of the production system.” Outdoors, “there is a lesser degree of control and rising risk of external factors, whether that is microbacterial stuff in the soil, etc., it’s a little harder to control quality.”

While most indoor facilities and greenhouses aren’t hybrids like the Aurora Sky facility, says Rewak, sources agreed the downside of indoor growing is that it’s the least energy-efficient method because of its use of artificial lighting and, adds VanderMarel, heating, lighting and ventilation (HVAC). Ultimately, this makes indoor production the more expensive option.

Marc LeBlanc, president of New Brunswick startup Solargram Farms Corp. says his company has strictly outdoor plans for now because the hope is this will significantly reduce the cost of growing cannabis. “The numbers that we see for indoor growers are anywhere between $1.50 to $3 a gram to grow. Our cost model is under 25 cents,” says LeBlanc.

While there certainly continues to be room for debate, one developing view is that carefully grown indoor cannabis makes for some of the best premium dried flower, while large-scale outdoor grown cannabis may fit the bill for those not-yet available extraction products.

(VanderMarel also voiced confidence that her company’s yields will come in roughly at 25 cents per g, while information on Canada Compliance Inc.’s website notes “production costs for a very efficient, large-scale indoor operation range from $1/g to $3/g, whereas outdoor farming, in theory, could bring commercial production costs below 25 cents per g based on our modelling.”)

LeBlanc further cites recent figures from Statistics Canada that indicate about 80 percent of cannabis consumers are still buying from the black market despite legalization. “That means it’s either the cost, or consumers are rejecting the products that are already in the cannabis stores,” he says.

Overall, indoor growing isn’t going away any time soon—48North, for example, will keep its two licensed indoor facilities for premium dried products—but as consumers look to purchase more extraction products once edibles and other products become legal, hoped this fall, licensed producers hope to lead the way with large-scale farms.

“I often use the analogy that you don’t see us growing canola oil or corn for ethanol in indoor facilities. They are outdoor productions and that is where any extractive product is grown,” comments VanderMarel.