Ultraviolet Light for Mold Control in Indoor Medical Marijuana Gardens

Mold and mildew can develop in both indoor and outdoor gardens but tends to be more devastating indoors, and can wipe out an entire crop if it is not controlled. Ultraviolet (UV) light can be used to eradicate mold spores that accumulate on floors or that spread via air currents. The primary mold spore of concern is usually Botrytis cinerea, a ubiquitous fungi that often contaminates soil and is easily brought indoors on shoes and clothing (see Figure 1). It is often referred to as “powdery mildew” and is also called “gray mold rot” or “grey mold” or “botrytis spots” or “storage rot” or “budrot” and is one of the most common fungal diseases of bell peppers and some fruits. It causes decay of plants and is absolutely and rapidly destructive of cannabis buds. Botrytis cinerea occurs as a spore and it is hardy and rather resistant to UV, and therefore requires a high UV dose to sterilize. There are some other mold and mildews that cause problems, but if a system is designed to control Botrytis then it will likely be effective at controlling other fungal contaminants.