Stewart Maxwell, Xylem Horticulture

"Growing cannabis organically is a sort of a niche"

Stewart Maxwell is a crop consultant who has always focused on growing organically. “It is a sort of a niche,” he says. “When you grow organically, there are different cultural practices that need to be carried out. These practices are outlined by different bodies that regulate organic certification. If a grower aligns with those, their operation can be qualified as organic.”

Stewart Maxwell

With his company Xylem Horticulture, Stewart provides crop consultations around Canada. “I was most recently under contract with a Canadian LP, for which I worked for 9 months. I supported them in building the cultivation team and in optimizing their cultural systems for organic production.”

The importance of IPM
One of the trickiest aspects in growing organically is the IPM. “Recently, there’s been a lot of focus on IPM, as chemical approaches are not allowed, or they just don’t work as they should.” He continues to explain that the highly regulated Canadian cannabis industry prevents growers from using any chemical crop protection. “There were some tools that worked well for heritage growers, but pests and pathogens develop resistances, and many of these products are not safe to use on cannabis. One way to tackle the issue is to have a special focus on the selection of the genetics.”

The selection of the cultivar
The selection of the cultivar is crucial, and going for the right one requires taking into consideration the kind of operation one is growing cannabis in. “Medical cannabis can be grown indoors, outdoors, or in a greenhouse,” he explains. “I have always preferred growing outdoors or in a greenhouse, as I have been specifically focusing on living soil, and feeding the soil. Because of this, I rarely fertigate, for instance.”

“From an IPM perspective, indoor allows growers to more easily run a clean facility, as many variables can be controlled. On the other hand, there is always pest pressure in greenhouses. The trick is to manage those pressures in order not to be economically damaged; and this is exactly where the selection of the right cultivar comes into play.”

“Indoor growers have been mostly looking for afghani type cultivars, with broad leaves, and short internodes,” he points out. “Greenhouse growers usually opt for plants with longer internodes, in order to allow more light into the canopy. If you want to grow medically in a greenhouse, it is important to work on the cultivar, to conduct some research to capture the quality that one wants to grow for.”

Being a young industry
The cannabis industry in Canada is surely thriving, but not without a few obstacles along the way. “There are so many jurisdictions involved, and also so many restrictions and compliance aspects. In Canada, companies are trying to grow within a very rigid framework, which is a complex endeavor. That is why there is some low-quality cannabis out there. At the same time, places like the US that have opened the industry to the free market, have different issues, such as product oversupply, and lack of pesticide regulation. This is because this is still a young industry, and how it functions is still largely dependent on the regulatory environments.”

Focus on growing
According to Stewart, the focus of the industry should be on growing plants. “Many companies have to learn how to grow cannabis, as their focus has mainly been on raising money. Continually raising capital is not a sustainable business model, and only by focusing on what differentiates ourselves from the rest, we can advance the industry and provide patients with safe and healthy products.”

For more information:
Xylem Horticulture  

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