It will kill insects and worms if they come into contact with the fine dust. Food-grade diatomaceous earth is a biosafe mineral that's harvested from the ocean.X Trustworthy Source National Pesticide Information Center Organization run by Oregon State University providing objective, science-based information about pests and pesticides Go to source

This insecticide is effective on tomato worms and pests such as spiders mites, mosquitoes, and ants. Spinosad is a natural substance made by soil bacterium.These organic insecticides are safer for human consumption than other inorganic compounds. Pyrethrins are derived from the Chrysanthemum flower and are used to control fleas, flies, moths, ants and other pests.Bt also kills cabbage worms, cabbage loopers, cutworms, and other harmful caterpillars. Botanical Bt (Bacillus Thuringiensis) is an organic insecticide that acts as a stomach poison and will not harm other plants or animals.

Be careful in choosing as some may be harmful to beneficial insects. There are many options of insecticide to pick from and the choices may seem daunting.

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