Diatomaceous earth (DE) kills many household pests, such as ants, fleas, and flies, when they walk or crawl over it. But DE kills good insects that come into contact with it too, like bees, butterflies, and ladybugs.
Not all diatomaceous earth is created equal in pest control. It’s important to choose food grade DE, like this one from Amazon. Pool grade DE (also sold as filter grade) has been heat-treated at extreme temperatures, making it far less effective, and also nastier to breathe in. Check the bag says food grade before you buy.
You’ll also need a duster to apply DE. Shaking DE straight out of the bag gives you thick white piles, and bugs walk around piles. You want a barely-there film they have to cross. A cheap bulb duster does that in seconds.
The full list of 47 bugs DE kills is below.
In this article, you’ll get:
- A list of 47 bugs that DE kills, including the good bugs
- A few things DE doesn’t kill that you’ll want to know about
- How DE kills bugs
- What’s in my DE pest control kit
- If DE is safe for pets
47 bugs that diatomaceous earth kills
Many pest control products that are registered with the US Environmental Protection Agency (EPA) have diatomaceous earth listed as an ingredient. In fact, the EPA has over 7 000 results for product labels with diatomaceous earth on them. [source]
Diatomaceous earth has been shown to kill the following, in alphabetical order:
- Ants (except carpenter, fire, harvester, and pharaoh ants)
- Aphids
- Army worms
- Bed bugs (cimexa powder works better for bed bugs)
- Bees
- Beetles, such as asparagus beetles, bean beetles, blister beetles, borer beetles
- Boxelder bugs
- Butterflies
- Caterpillars
- Chinches
- Cockroaches
- Crickets
- Earwigs
- Fleas
- Flies, such as blow flies, fruit flies
- Gnats, including fungus gnats
- Grasshoppers
- Green lacewings
- Katydids
- Ladybugs
- Leafhoppers
- Lice
- Loopers
- Maggots
- Mealybugs
- Mealworms
- Millipedes
- Mites
- Mosquitoes
- Moths
- Plant bugs / leaf bugs / grass bugs
- Plant lice (psyllids)
- Scales
- Silverfish
- Skippers (part of the moth and butterfly family)
- Slugs
- Snails
- Spiders
- Stink bugs, including green bugs
- Termites
- Thrips
- Ticks
- Tomato bugs, fruit worms, hornworms, pinworms and russet mites (click here to find out what’s eating your tomato plants at night)
- Wasps, including chalcids and yellow jackets
- Weevils
- Worms, such as army worms
If good (non-pest) bugs walk or crawl over diatomaceous earth, they die too. This includes bees, butterflies, green lacewings, and ladybugs.
What diatomaceous earth doesn’t kill
Of course, there are many things that diatomaceous earth doesn’t kill. Here are a few that you might be wondering about…
Diatomaceous earth won’t kill:
- Carpenter ants
- Earthworms
- Fire ants
- Harvester ants
- Internal parasitic worms, such as tapeworms (studies have not been able to prove that DE works as a dewormer, even though many people say it does)
- Pharaoh ants
How diatomaceous earth works
Diatomaceous earth is an inexpensive, chemical-free, non-toxic, natural product made from the shells of fossilized microscopic algae. But it’s deadly to many bugs and can be dangerous to humans and animals if the dust is breathed into the lungs.
Diatomaceous earth doesn’t attract bugs or bring them out of hiding. DE can only harm or kill bugs that come into direct contact with it.
DE is like tiny shards of glass to bugs: When a bug walks or crawls over DE, the DE cuts the bug’s exoskeleton. The bug loses moisture through these cuts, and it dehydrates and dies.
On average, bugs die about a day or two after coming into direct contact with diatomaceous earth. If you use DE as a pesticide, you’ll probably need to leave it out for several days or more, until all the pests have had a chance to come into contact with it.
When choosing diatomaceous earth as a pest control, it’s best to choose a food-grade product (such as this one on Amazon) or a product registered with the EPA. Always follow the instructions on the packaging to avoid harm.
Because diatomaceous earth is a natural mineral, it never expires or goes bad. If you have a bag and you keep it in a dry place, it will last forever.
What’s in my diatomaceous earth kit
After a few seasons of using this stuff, here’s what I keep on hand. You don’t need all of it on day one, but the first two are non-negotiable.
- Food grade diatomaceous earth — 10lb bag is better value than small tubs if you’re treating a yard or crawl space; 5lb OMRI-listed version if you need less.
- A bulb duster — Harris Powder Duster turns a messy job into a 5-minute one, and you use maybe a third as much product.
- A dust mask — food grade is safe to eat, but it’s still a fine powder and you should not be breathing clouds of it. 3M N95 respirator masks.
- Cheap paintbrush — 3-pack small paint brushes for pushing a thin line along baseboards and door frames where a duster is overkill.
- Squeeze bottle with a long nozzle — crack-and-crevice applicator for wall voids, behind appliances, under the fridge.
A few things worth knowing before you spread DE around:
- It only works dry. Rain or heavy dew and it’s done — reapply once things dry out.
- It’s slow. Give it 24 to 72 hours. It’s not a spray, nothing dies on contact.
- It doesn’t know the good bugs from the bad ones. DE will kill bees, ladybugs and lacewings just as happily as it kills ants. Keep it off blooms and anywhere pollinators are working.
Is diatomaceous earth safe for pets?
Food grade DE is low-risk for healthy pets — it’s not on the ASPCA’s toxic list. The real danger is inhalation, and it’s worse for pets with asthma or other breathing problems, where heavy exposure can trigger a serious reaction. Keep application light, never a visible dusting, and away from where your pet sniffs or settles.
If your pet coughs, wheezes, or struggles to breathe after exposure, get them to fresh air immediately and call your vet — don’t wait it out, especially if they have any history of respiratory issues.
