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While most spiders are not dangerous, brown recluse spiders, which have a signature violin-shaped marking on their backs, can be. Being bitten by a brown recluse can cause headache, fever, body aches, nausea, and vomiting, as well as pain and discoloration at the location of the bite. If you want to keep brown recluse spiders out of your home — or kill any spiders inside your house – diatomaceous earth is an effective repellent and extermination method for these arachnids.
Some chemical pesticides can be dangerous for people and pets, but diatomaceous earth is made of natural substances and is generally considered non-toxic and safe to use around the home. According to Main Street Veterinary Services, food-grade diatomaceous earth won’t harm your pets if you use it in the house for pest control. Though it’s safer than other extermination options, this fine powder could irritate the lungs, skin, or eyes if you come into direct contact with it.
Why diatomaceous earth works against brown recluse spiders
Diatomaceous earth is made of fossilized diatoms – a type of microscopic algae. The fine powder has extremely sharp edges that will cut into spiders’ exoskeletons. Once spiders come into contact with the natural pesticide, it will soak up the arachnid’s fats and oils and dehydrate them. The damage to the exoskeleton and loss of fluids will kill the pests, but in most cases, this is a slower process, and it will take time to exterminate the spiders.
This non-toxic pest control method is not only effective against brown recluses; it affects all spiders and some other insects, including stink bugs, bed bugs, cockroaches, fleas, ants, ticks, mites, and silverfish. Because insects don’t need to consume the pesticide, simply sprinkling diatomaceous earth in areas where you’ve seen spiders can affect these pests. With a little diatomaceous earth, you can kill the brown recluse spiders in your home and prevent more from sticking around.
How to use diatomaceous earth
When purchasing your diatomaceous earth, make sure it is food grade — rather than industrial or feed grade, as this variety is the safest to use inside the home. Before applying your natural pesticide, read all directions on the packaging and put on a dust mask and rubber gloves. This will ensure that you don’t accidentally inhale the powder or irritate your skin.
Because brown recluse spiders are known to hide, you’ll need to spread your diatomaceous earth in several areas of your home, such as between walls, in your basement, any cracks in your floors or walls, or other areas where you’ve found evidence of the spiders. You’ll need to spread an even, thin layer of the powder in these places — using a powder duster ($9 on Amazon) can make the job quick and easy. Diatomaceous earth can also be used outdoors to deter brown recluse spiders from coming inside your home. Spread the powder around doors and windows or along the edges of your house.
