If you’re sick of silverfish, we’ve got the solution
When you’re sitting in your bedroom curled up with a good novel, few things are more startling than the sight of a silverfish racing across the wall. But how do you get rid of these speedy little things?
Fear not. This guide breaks down how to spot signs of an infestation, how to get rid of silverfish, and how to make sure they never return.
Silverfish are small, wingless insects that feed on sugar or starches. They are found all over the world and like to inhabit areas with high humidity, which is why they are often discovered in basements and bathrooms.
Typically, silverfish will crawl into your home through gaps in your foundation. But they can also hitch a ride into your house via cardboard boxes—particularly ones that are a little damp.
You’ll be able to identify this insect by the following features:
Extended antenna and tail
Flat body with six legs
1/2–3/4-inch long
Silver or brown color (hence the name)
The good news is that silverfish aren’t typically dangerous to humans. They can’t bite you, but they can cause an allergic reaction—especially if you’re allergic to dust mites.
However, the major problem with a silverfish infestation is property damage. They feed on textiles and can bite holes in silk, cotton, linen, and more. They can chew up books, carpet, and art. They notoriously feed on plaster and drywall.
Since silverfish can live up to three years, a small silverfish problem can quickly become a big one. The cost of pest control is typically $200 to $600 if you hire a professional. If you do the job DIY, you’ll just have to pay for supplies like silverfish repellent or bait.
Most of the time, you won’t really see silverfish in your home. They are stealthy and hang out inside walls and crawl spaces. They typically only come out at night to feed. So, how do you know you actually have an infestation? Here are some telltale signs:
Where there’s a couple silverfish, there’s probably more. Multiple silverfish scurrying around in a humid, moist area like your basement is typically a sign of an infestation.
Silverfish leave behind feces in areas where they feed, such as in books or on your carpet. Silverfish feces are shaped like tiny pellets that might look like black pepper. You may find a large amount of feces clumped together in an infested area that will be impossible to ignore.
In addition to feces, silverfish leave behind marks where they feed. You might notice tiny holes and dark or yellowish marks on items like books, magazines, artwork, plaster, clothing, and glue. Anything with adhesive is fair game.
Silverfish regularly molt as they age. In addition to a yellowish residue, you may find their actual molted shells. These are small and transparent.
Silverfish prefer to lay their eggs in moist areas with crevices. A female will lay a group of potentially dozens of eggs that are oval and off-white. It will take a few weeks to hatch, and the nymphs will appear paler and smaller than adults.
There are multiple ways to get rid of a silverfish infestation in your home. Choose any or all of the below methods to kill these unwanted houseguests and help prevent them from returning.
Many silverfish repellent sprays are actually made from cedar oil. When applied in high concentrations, the oil knocks them dead—but most homeowners use it for the scent, which is a powerful deterrent.
Mix a few drops of cedar oil with water to make a DIY spray. Spray it around baseboards, inside cabinetry, and wherever else you notice silverfish activity. You can even use an essential oil diffuser to spread the smell around your home.
While cedar oil is the most common solution, there are a few other essential oils that help repel bugs.
Consider using products with the following scents as silverfish repellent:
Orange
Lemon
Cinnamon
Bay leaf
Clove
Lavender
Peppermint
Rosemary
Put a thin layer of boric acid or borax powder along baseboards, the back of cabinets, and the inside of closets to kill silverfish. This method is particularly effective if you know where silverfish are entering your home.
Keep in mind that though boric acid is mostly safe, it’s harmful when ingested or inhaled, says the Centers for Disease Control and Prevention. Don’t use this method if you have pets and children.
Get rid of silverfish by making your own DIY pest traps using common household items.
Here are two of the most popular methods:
The glass jar method: Fill a glass jar with flour, cereal, or pet food as bait to attract silverfish. Wrap the outside of the jar with a textured tape, like masking tape, which they can use to climb into the jar. The silverfish won’t be able to climb back out.
The newspaper method: Roll up a damp newspaper and leave it out for a few days as bait. Silverfish will move in and start to make their nests. Once they do, get rid of the newspaper.
Once you catch the silverfish, make sure to throw out the trap in an airtight container. If there’s a crevice, the silverfish will take that opportunity to sneak away.
Most traps that are manufactured to kill silverfish contain some sort of poison, typically boric acid. These can pose a risk to children and pets, but as a safer alternative, you can use a regular sticky trap. If you go this route, put the traps in areas where you’ve noticed silverfish in your home.
Insecticides are a sure-fire way to kill silverfish. These are available in bombs or sprays, and you can purchase them at your local hardware store. Keep in mind that this is a last-resort option. Pesticides are dangerous to children, pets, and just about anyone else in your household when used incorrectly.
According to the National Poison Control Center, pesticides caused nearly 70,000 poisonings in 2020, but an exterminator near you can help you use them safely.
Once you get rid of your initial infestation, you need to make sure these pesky critters never return. The source of the problem isn’t always an easy fix, especially if you live in a humid climate, but there are some ways you can keep your home pest free.
Silverfish thrive in humidity, so it’s crucial you fix damp areas in your home ASAP. You may need to fix plumbing leaks, worn-down waterproofing around windows, or dampness in an unencapsulated crawl space. If you can’t find the source of your humidity problems, consider investing in the cost of a whole house dehumidifier.
The most natural way to get rid of silverfish is to remove their food source, which is a good solution for getting rid of any bugs in your home. If you've noticed they like chowing down on old books and magazines you keep in your basement, remove them and find an alternative method of storing them. Also, keep flour and sugar in containers they can't access.
Once you get rid of the food source, remove as many hospitable places for silverfish eggs as possible. Silverfish lay their eggs in dark, moist, well-protected areas—typically cracks and crevices. For example, if you have a localized infestation, you may want to remove stacks of boxes in your basement or that old magazine rack in your bathroom.
Silverfish are good climbers, so if you have items leaning against your home they can climb to get inside through pipes and vents, you should move them. If you've noticed a widespread infestation instead of a localized one, this is the most likely cause.
Silverfish love moist, humid environments, so get a dehumidifier in your basement or other living areas to make the environment inhospitable for them.
Silverfish love to hide among clutter—and a lot of that time, clutter is what they actually eat. They will dine on magazines, books, newspapers, cardboard, and even things like dust and dandruff. To stop the problem, clear away the clutter and make sure your home is always clean and dust-free (at least as much as your busy schedule allows).
Since silverfish eat the same carbohydrates we enjoy, don’t give them a free ticket to the buffet. Keep dried snacks and ingredients like cereal, pasta, sugar, flour, and rice in airtight containers. They can eat through cardboard packaging and find their way inside.
There are some smells that silverfish naturally can’t stand. Luckily, they’re the same ones humans love. To deter these pests, you can place the following silverfish repellents in drawers, cabinetry, bookshelves, or any other area that these insects frequent:
Cedarwood blocks
Dried bay leaves
Dried cloves
Cinnamon sticks
Citrus peels
Cucumber peels
Lavender potpourri
Dried rosemary
Dried peppermint
If you do use fruit peels, remember to replace them regularly or they’ll attract a whole different host of pests (hello, ants).
If you only have a small infestation, you might be able to get rid of silverfish on your own. After deep cleaning your home and removing their food source, spraying a silverfish repellent might be very effective.
If you have a more serious infestation, it’s best to call a pest control company. A pest control company will be able to identify what is fueling the infestation and how the silverfish are gaining access to your home, as well as recommend a course of treatment.
Silverfish are deterred by scents like cedar, orange, lemon, peppermint, rosemary, bay leaf, clove, cinnamon, and lavender. You can use essential oils to spray these scents around problem areas.
Boric acid is a very effective way to kill silverfish. You can purchase a boric acid-based silverfish trap from your local hardware store, or alternatively, use sticky traps.
Silverfish are attracted to moist, damp spaces, which is why they’re often found in basements, bathrooms, and attics. They come in through cracks in your foundation, holes in screens, and any other crevice they can use as an access point. Sometimes, they’re even dragged in via boxes and other items you bring into your home.
Silverfish don't like the smell of cedar, citrus, cinnamon, and lavender, which is why these scents are commonly used in silverfish repellent sprays.
It is normal to notice a silverfish every now and then if you live in a damp climate. They live in the soil around your home, so they occasionally find their way inside. If you notice more than a couple, you may have an infestation.
