Skip to content

How To Use Diatomaceous Earth For Fleas

Diatomaceous earth (DE) is an excellent insect killer that is both nontoxic and long-lasting. It has long been used in the control of fleas, bed bugs, ants, and other household pests. Diatomaceous earth is a naturally occurring powder that is made from the microscopic remains of a type of algae, known as diatoms. The shells of diatoms are made out of silica, which is mined from ancient freshwater lakes and then crushed into a fine powder. This powder is soft to the touch of humans, but has microscopic razor-sharp edges that will kill insects, such as fleas.

Recommended Read: What is Diatomaceous Earth?

Instead of poisoning the fleas, diatomaceous earth cuts their hard exoskeleton (outer shell) leaving them vulnerable for moisture loss. DE is highly absorbent and will then suck the moisture away from the pest until it dies of dehydration. After coming in contact with the diatomaceous earth, fleas may die in as little as 4 hours, though it is recommended to leave the DE for up to 48 hours to ensure its effectiveness.

A closeup image of a flea


Application Tips for Flea Control

Diatomaceous earth can be used indoors or outdoors, and will remain effective as long as it stays dry. It is generally considered to be safe to use around pets and humans, but since it is a dust, you should still try to avoid having it blow around, as it may be slightly irritating. Please follow all product label instructions when applying this and any other pesticide product.
  • Start by locating the areas in your home or yard where you have seen fleas or your pets spend a great deal of time. Places to consider may include: furniture, pet beds, floors, cracks and crevices, under sinks, and even in gardens. If infested areas consist of carpeting, bedding, or other textiles, you may want to give it a good vacuum first to get the fleas moving.
  • Next, sprinkle the DE powder over the surfaces you want to treat. You want to apply it in a thin, uniform coating. If you are applying it to carpet, work it into the carpet using a broom to ensure that it gets deep into the fibers. If the areas are hard to reach, you can use diatomaceous earth in a duster or puffer bottle.
  • Leave the powder for a day or two so that it can do its job. Then thoroughly vacuum up the powder and dead fleas. If the treated area is out of the way, it can be left there as a preventive measure, and it will be effective as long as it stays dry.
  • Repeat this process once a week for 3 or 4 weeks to ensure that all eggs have hatched and adults and nymphs have been exterminated.



Diatomaceous earth is great forflea control because it is pesticide free and easy to use. Also, since it is a mechanical killer, fleas will not develop immunity to it. Use a quality diatomaceous earth for best results, and avoid using DE that is labeled for pool and aquarium use, as it has been chemically treated and can be dangerous if inhaled or ingested. If you are struggling with fleas, give diatomaceous earth a chance. TrustHarris products for all of your pest control needs. Checkout Our Article on How to Clean Up Diatomaceous Earth