Diatomaceous earth is an excellent tool for killing silverfish. The fine powder destroys the outer coating of silverfish and dehydrates the bugs, killing them. In fact, because silverfish love moist places and die quickly in dry environments, diatomaceous earth is one of the best natural products for killing silverfish. You can dust moist areas of your home—such as bathrooms and basements—with diatomaceous earth. Also, since it poses no threat to humans and pets, you can use diatomaceous earth in your kitchen and along baseboards to kill silverfish quickly and easily.
Why Does Diatomaceous Earth Kill Silverfish?
The reason diatomaceous earth is such an effective silverfish killer is that it scrapes away the outer scales of silverfish and dehydrates them. Because silverfish scales are fragile and these insects only survive in moist environments, diatomaceous earth is even more effective against silverfish than it is against other bugs.
- Diatomaceous earth cuts and scrapes silverfish, then dehydrates and kills them.
- Silverfish do not have a waxy coating, so they are more quickly affected by diatomaceous earth than other insects.
- More than other insects, silverfish need dampness and humidity, so they are very vulnerable to being dried out by diatomaceous earth.
In order to be killed by diatomaceous earth, all a silverfish has to do is walk through a dusting of the powder. The killing effects are not instant, but if a silverfish has to travel through diatomaceous earth to reach food or its nest, this will be enough to kill the insect.
Is Diatomaceous Earth Safe to Use for SIlverfish?
As long as you use food-grade diatomaceous earth, you can kill silverfish without posing any risk to yourself and your family. Diatomaceous earth is made up of the fossils of single-celled organisms, called diatoms. This results in a fine powder that is abrasive and dehydrating to insects, but is harmless to humans and other mammals.
- This food-grade diatomaceous earth is entirely pesticide-free and safe for use in your home.
- Diatomaceous earth is made up of fossilized single-celled organisms, so it contains no harmful chemicals.
- Do not use pool-grade diatomaceous earth—it can irritate your airways if inhaled.
There are no pesticides or other harmful chemicals in diatomaceous earth. This makes it safe for use in the kitchen. Very few other silverfish-killing products can be used to protect your food from these insects. So, diatomaceous earth is a very good choice for stopping silverfish infestations.
5 Ways to Kill Silverfish with Diatomaceous Earth
You can quickly kill silverfish and other household pests with diatomaceous earth. Just use these tips to treat the areas silverfish love to feed, hide, and lay their eggs. You will see results quickly.
Kitchen Shelves
Silverfish are known for invading cabinets to search for crumbs or chew their way into food packaging. Since silverfish are nocturnal, you may not notice this until it’s too late. To kill silverfish in your pantry, dust the shelves where you store your food with a thin layer of diatomaceous earth. Since it is non-toxic to humans, you don’t have to worry about diatomaceous earth contaminating your food.
Book Cases
Silverfish are notorious for eating books. Specifically, they are drawn to the glue used to bind books together. In order to protect your books and kill silverfish, spread a thin, even layer of diatomaceous earth on your bookshelves. Dust the area of the shelves both in front of and behind your books.
Bathrooms
Silverfish are attracted to moisture and humidity. It is common for them to hide in bathrooms during the day, even going so far as crawling into bathroom cabinets and beneath sinks. To kill silverfish and prevent them from laying their eggs in your bathroom, dust diatomaceous earth in bathroom cabinets, behind toilets, and around bathroom fixtures.
Along Baseboards
Silverfish commonly enter the gap between the baseboard and the floor. These gaps make perfect nesting places for silverfish to lay their eggs. In order to stop this activity, pour a line of diatomaceous earth along your baseboards throughout your home. Then, use a hair dryer to gently blow the diatomaceous earth into the gap between the baseboard and the floor. This will kill silverfish where they hide. However, it’s a good idea to wear a dust mask and eye protection during this process to avoid irritating your eyes and nose with diatomaceous earth powder.
In Damp Rooms and Basements
Damp, dark areas of your home make for perfect silverfish hideaways. In fact, your silverfish infestation may be coming from your basement or a utility closet. Make sure to dust the floors of rarely-used, moist rooms to kill silverfish and eliminate them from your home. It’s also a great idea to dust shelves in your basement to keep silverfish at bay.
How Long Does it Take for Diatomaceous Earth to Kill Silverfish?
Diatomaceous earth will begin to kill silverfish within 1–2 days after you spread it in your home. Silverfish do not die instantly upon coming into contact with diatomaceous earth, but if they walk through it in order to feed, hide, or nest, it will dehydrate and kill them within 24 hours.
- Silverfish will begin to die within 24–48 hours of exposure to diatomaceous earth.
- The more a silverfish walks through diatomaceous earth, the faster it will die.
- For more tips on getting rid of a silverfish infestation, check out our top ways to exterminate silverfish.
If you have a silverfish infestation that you want to take care of immediately, you can take more drastic measures. However, diatomaceous earth is very effective. If silverfish are not killed they can live for up to 8 years, and the females can lay hundreds of eggs.
Do Silverfish Eat Diatomaceous Earth?
Silverfish do not eat diatomaceous earth, nor do they need to eat the powder in order to be killed by it. Instead, merely walking through diatomaceous earth is enough to damage, dehydrate, and kill silverfish. So, you don’t need to worry if the silverfish have “taken the bait.” If you dust diatomaceous earth where you have seen silverfish in your home, you will kill them the next time they walk through that area.
Do Silverfish Avoid Diatomaceous Earth?
Silverfish do not avoid diatomaceous earth. In fact, silverfish do not have a complex nervous system or brain capable of understanding that diatomaceous earth is harmful to them. They will walk through diatomaceous earth the same way they would walk across dust. The silverfish in your home won’t know they are being exterminated until they’re already dead.
How Do You Use Diatomaceous Earth to Kill Silverfish?
There are several excellent ways to use diatomaceous earth to kill silverfish. Since it is completely harmless to humans and pets, here are the best ways to use food-grade diatomaceous earth to eradicate silverfish:
- Dust your cabinet and pantry shelves with diatomaceous earth powder.
- Spread diatomaceous earth in a fine layer on your bookshelves.
- Coat damp, dark, and hidden areas of your bathroom with diatomaceous earth.
- Spread a trail of diatomaceous earth powder along your baseboards, then use a hair dryer to blow the powder into the gap between the baseboard and floor.
- Dust the floors of basements and damp storage spaces with diatomaceous earth.
Diatomaceous earth works quickly to kill silverfish. Plus, as long as it stays dry, diatomaceous earth remains effective. Any new silverfish that hatch will quickly be killed when they walk through diatomaceous earth.