A well-known integrated pest management system, known as diatomaceous earth, has been approved for Canada’s cannabis cultivation. This pesticide is comprised of silicon dioxide – a natural substance. (1)
What is diatomaceous earth and where did it come from?
In reality, diatomaceous earth, or diatomite, is simply a sedimentary rock. Diatoms are single-celled algae that collect in the sediment lakes and oceans as they die. The accumulation of these fossilized organisms forms diatomite, or diatomaceous earth, which can now be used for cannabis cultivation.
How is it used?
This sedimentary rock can be used in the soil of cannabis. Diatomite is abrasive and physically tears apart a pests exoskeleton, but is also absorbent and will dry out insects as well. The recently approved products, however, are intended for use directly on cannabis plants strictly in the vegetative state.
DX13 Dust and DX13 Industrial by DE Laboratories Inc. were approved for use on cannabis crops by the Pest Management Regulatory Agency (PMRA.)
The use of diatomaceous earth on vegetative cannabis plants is intended to help treat spider mites.
Are there safety concerns?
An N95 respirator must be worn when applying either approved product according to respective label instructions. No person’s or pets are allowed in the area or room when applying Diatomaceous Earth. This is due to a potential risk of lung cancer from the inhalation of silicon dioxide. However, the label instructions restrict the pesticide on flowering cannabis plants.
According to an MSDS associated with another (pressurized) version of DX13, the ingredients include ethyl alcohol, propane, and butane. These substances would act as solvents if applied to a budding cannabis plant rather than a vegetative one. (3)