A well-known integrated pest control system known as diatomaceous earth has been approved for cannabis cultivation in Canada. This pesticide is made up of silicon dioxide – a natural substance. (1)
Food grade diatomaceous earth. (2)
What is diatomaceous earth and where does it come from?
In reality, kieselguhr or kieselguhr is simply a sedimentary rock. Diatoms are unicellular algae that collect in sedimentary lakes and oceans when they die. The accumulation of these fossilized organisms forms diatomaceous earth or diatomaceous earth, which can now be used for growing cannabis.
How is it used?
This sedimentary rock can be used in the soil of cannabis. Diatomaceous earth is abrasive and physically rips the exoskeleton of a pest, but it is also absorbent and dries out insects too. However, the recently approved products are intended for direct use on cannabis plants only in the vegetative state.
DE Laboratories Inc.'s DX13 Dust and DX13 Industrial have been approved by the Pest Management Regulatory Agency (PMRA) for use in cannabis cultures.
The use of diatomaceous earth in vegetative cannabis plants is believed to help treat spider mites.
Are there any safety concerns?
An N95 respirator must be worn when using any of the approved products as instructed on the label. When using kieselguhr, no people or pets are allowed in the area or in the room. This is due to a potential risk of lung cancer from inhalation of silicon dioxide. However, the instructions on the label limit the pesticide to flowering cannabis plants.
Photo courtesy DX13.
According to a safety data sheet 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)
Let us know in the comments what you think about using diatomaceous earth in growing cannabis. And stay tuned to learn about other pesticides in the industry.