Diatomaceous Earth for Flea Control

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Diatomaceous Earth (DE) is a fine flour-like powder, the microscopic remains of fossilized diatoms, a type of algae. Diatoms are found in freshwater and saltwater. Capable of photosynthesis, they are an important food source for many organisms in these water ecosystems.

Diatom cell walls are made of silica, a component of glass. DE has been used for years as an insecticide to control mites, fleas, and other insects; find out how it works here.

How Diatomaceous Earth Works to Kill Fleas and Other Insects

Fleas and other insects with an exoskeleton (hard shell) are susceptible to the glass-sharp edges of the microscopic diatoms. The silica shards cut through the waxy exoskeleton surface, effectively drying out the flea, resulting in death to these types of insects and their larvae.

Diatomaceous Earth Pros and Cons


  • The good news is that Diatomaceous Earth is non-toxic to humans and animals; it is even used in some foods food (food-grade quality, not the DE used for pool filtration systems) and some health supplements. DE is also used for a variety of beauty and healthcare products.
  • Daily vacuuming is an important component of household flea control. Diatomaceous Earth can be used safely on many surfaces and floor coverings, vacuuming up the DE after allowed to sit for at least a few hours or overnight. A few days, if doable.
  • Diatomaceous Earth is safe to use on pet bedding, in addition to weekly washing of pet bedding in warm water.
  • Diatomaceous Earth is safe to use around the yard, but large amounts may be necessary to have a positive effect on flea control. Regular mowing and trimming of vegetation also help. For serious flea infestations of yard and garden, a consultation with a pest exterminator is in order.
  • Diatomaceous Earth is not toxic, does not have any residual problems, and because it is a mechanical killer versus a chemical killer, resistance to DE is not a problem.


    • Diatomaceous Earth is a very fine, silky powder; similar to flour or talc. It is messy and may irritate eyes and throat. Use caution and wear a face mask when applying. Food grade DE is okay to ingest, so it is not toxic to pets or people, but may be temporarily irritating.
    • Diatomaceous Earth that is used for pool filtration systems is very finely ground and is dangerous to breathe in. It is not recommended for flea and insect control.
    • Diatomaceous Earth must be dry to work. Wetting it down or trying to mix it with water to spray it and not breathe in dust negates the useful action of DE. Always wear a mask when applying DE.
    • Related to this, Diatomaceous Earth is less effective in humid environments.
    • Some advocate using Diatomaceous Earth directly on pets. Caution is advised if you elect to use it on your pet. Use food grade DE only. DE is very drying - it may dry out your pet's skin. Protect your pets' eyes, nose, mouth when applying. Shampoo your pet within 12 hours, a conditioner is recommended.

    Fighting Fleas

    Fleas are a pain to deal with, for pets and people. Fighting fleas effectively necessitates knowing about the flea life cycle and addressing fleas both on the pet(s) and in the environment.

    Diatomaceous Earth is a safe and effective add-on to an existing plan or as a standalone flea fighter. There are many flea treatments available, depending on the severity of the problem, the climate, and your pet's overall health. Your veterinarian can help tailor a flea-fighting plan specific to your needs.