Prof. Youbin Zheng, School of Environmental Sciences, spoke with the Toronto Star about some of the challenges of home-growing cannabis now that the first legal harvest is underway.

Zheng said he’s heard some backyard growers have been having better yields this year than they had when trying to grow pot surreptitiously. He explained that sunlight conditions control the timing of most outdoor cannabis harvests in southern Ontario, since the plant requires 10 to 12 hours of uninterrupted darkness to maintain flower growth.

Zheng has co-authored several ground-breaking papers examining optimal horticultural practices to produce high-yielding, high-quality cannabis. He studies greenhouse production, hydroponics, and controlled environment plant production.