Diatomaceous Earth for Flea Control

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When fleas invade a home, it's time to wage war—but the battle isn't easily won. Fleas are hardy creatures that are hard to get rid of, but there are available tools that might help you claim victory. This includes diatomaceous earth (DE), a fine flour-like powder made of the microscopic remains of fossilized diatoms, a type of algae.

Diatom cell walls are made of silica, a component of glass, and fleas and other insects with a hard exoskeleton 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 and resulting in death to these types of insects and their larvae. It's a non-toxic way to rid your home of fleas, but only if you're careful to use it safely and appropriately.

How to Use Diatomaceous Earth Effectively

Food-grade DE is safe for use around humans and animals, but you want to make sure that's the type you purchase. You might also come across DE for use in swimming pool or charcoal filters (pool-grade DE), but it's not safe to use in your home. When you've brought the DE home, follow these steps:

  1. Don garden or kitchen gloves to keep your hands from touching the DE. Though it's safe, it's very drying to your skin.
  2. Sprinkle the DE on carpets, dog beds, soft furniture and any other place you think the fleas have invaded. Leave it for three days, and then thoroughly vacuum up the powder.
  3. Repeat every week for 30 days, vacuuming up the powder three days after application each time.

Leaving the powder on the carpets for three days and repeating the process every week for a month ensures that the adult fleas are destroyed, as well as the eggs and larvae.

Pros and Cons of Diatomaceous Earth

It's easy to get your hands on diatomaceous earth at a gardening store or by ordering online. But you'll have to weigh the pros and cons of using it. On the plus side:

  • Diatomaceous earth is safe to use on pet bedding. However, it's also smart to wash your pets' beds in hot water once a week.
  • DE 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 cause any residual or lingering issues, and because it is a mechanical killer versus a chemical killer, the fleas will never develop immunity to it.

There are drawbacks, too:

  • DE is a very fine, silky powder that's similar to flour or talc. It is messy and may irritate eyes and throat. Use caution and wear a face mask when applying. Although food-grade DE is OK to ingest, it can be temporarily irritating.
  • 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. Because of this, diatomaceous earth is less effective in humid environments.
  • While it's not dangerous to apply DE directly to your pet, caution is advised. Talk to your vet first, and consider using alternative methods. DE is very drying and you should protect your pets' eyes, nose, mouth when applying. Shampoo your pet within 12 hours, finishing up the bath with a conditioner.