Silverfish, while harmless, are creepy bugs that can ruin a number of personal items, like clothing and books.
If you have a silverfish problem, Pest Strategies is here to help. This article covers the best methods to get rid of silverfish. You’ll learn:
- What attracts silverfish to your home
- Four natural silverfish remedies
- Two methods that remove silverfish with pesticides
- Three bonus remedies
- And how to prevent an infestation in the first place
Silverfish don’t attack humans, they don’t bite us, or transmit diseases to us. Silverfish are related to firebrats and are actually kind of harmless.
That being said, they’re certainly pests. The silverfish diet consists of cellulose, book glue, dead insects, shampoo, clothing like linen or silk, old newspaper, and food crumbs.
They can also leave yellow stains and small holes in your clothing.
What Attracts Silverfish in the First Place?
These pests are silver and teardrop-shaped, about an inch long, with two long antennae in front.
Silverfish like to hide in dark damp cracks and crevices where people can’t see them, and they prefer to come out only at night. Any place in your house that is dark, damp, humid, and warm (not hot) will attract silverfish.
Silverfish can survive in almost any climate but they much prefer the cool, dark, humid areas of the world, including your house. They’re attracted to high humidity and damp places like a magnet.
This video from Expresso goes into detail about what silverfish are, where they come from, and why they exist.
4 Natural Remedies to Get Rid of Silverfish in or Around Your House
Silverfish control without an exterminator can be achieved in a number of different ways. Let’s look at a few pest management options.
If you want to use cinnamon sticks, put them out in areas where silverfish are most likely to appear; under sinks, closets, basements, laundry rooms, and so forth. They will smell the odor and be repulsed by it.
Another way to use cinnamon is to put ground cinnamon in a sachet (a small cloth pouch) and put it out in the same areas. In either case, you’ll have to replace it once it gets damp.
Cinnamon is a popular way to kill silverfish or repel them. There is very little research available to back up this claim, however. What research there is, simply mentions cinnamon without supporting any claims to its efficacy.
An essential oil that repels silverfish is lavender oil.
Mix a teaspoon of lavender oil with a cup of water in an 8-ounce spray bottle. Shake thoroughly then spray it on the cracks and crevices around baseboards, cabinets, under sinks, etc.
Your kitchen will immediately smell fresh and inviting as well as potentially repelling the silverfish. Lavender doesn’t have a strong residual impact though, so you’ll have to reapply it every 3-4 days for best results.
Again, it’s difficult to find research that specifies lavender as a repellent for silverfish, lavender is known to repel moths.
Since moths and silverfish are attracted to similar environments and food, it stands to reason that lavender will be effective on both.
Cedars contain natural insect repellents that are useful for keeping silverfish out of your home. Cedar closets are famous for their ability to repel moths and protect your clothes from being eaten by them.
Silverfish are affected the same way.
You can use this natural property by spreading cedar shavings around the outside of your house. They are – obviously – biodegradable so there is no environmental hazard to them.
As cedar shavings degrade, they’ll release their scent and push silverfish and other insects away from your home.
Every few months, put out some more cedar shavings to maintain the barrier around the house.
Put out a band of shavings at least 12-19 inches wide. You can distribute them by hand. For an average house of 1800 square feet, 2-3 bags of shavings should be sufficient.
Diatomaceous earth (DE) is made from miniature aquatic sea creatures called diatoms. Their fossilized remains contain silica. There are two modes of action for food grade diatomaceous earth.
One mode of action is that it absorbs oils and fats from insect exoskeletons, which causes them to dry up and die.
Another mode of action is that diatoms leave behind tiny, razor-sharp shells. The edges are abrasive, cutting the insect’s exoskeleton, causing them to lose moisture even when the DE itself is wet.
Because insects are so small, the loss of any liquid from their system is fatal. This is why either mode of action effectively kills silverfish.
Both modes of action are mechanical, that is, there is no chemical activity so it is completely safe. And because DE works even when it’s wet, it is well suited to be used outside.
Sprinkle a fine band of DE all the way around the house. You can sprinkle it next to the house, then put another band of it in the grass, creating a double layer of protection.
2 Pesticides to Get Rid of Silverfish in Your House
There are six different kinds of pyrethrins: Pyrethrin I, pyrethrin II, cinerin I, cinerin II, jasmolin I, and jasmolin II.
Pyrethrins are pesticides that come from chrysanthemum flowers. Technically, they’re a natural remedy, but they’re usually mixed with another chemical to increase their efficacy.
Pyrethrins work by paralyzing a pest which ultimately lead to its death. They're effective on silverfish as well as other small household pests like mosquitoes, flies, fleas, and ants.
Applying this pesticide is simple. You mix a certain amount (depending on which pyrethrin product you buy) with water in a sprayer, shake until thoroughly mixed, and spray!
Spray all the baseboards throughout the entire house:
- Under sinks
- Around toilets
- Under and behind major appliances
- Around doors and windows
And spray every other place you’ve seen evidence of a silverfish infestation
Reapply the spray once a month for three months and the silverfish should be gone.
Two effective pyrethrin-based products are Suspend SC and Tempo Ultra SC.
Permethrin is similar to pyrethrin, but with one big difference. Whereas pyrethrins are naturally extracted from chrysanthemum, permethrin is synthetic and only mimics the actions of pyrethrin.
However, the results are the same. Permethrin affects the nervous system. Like pyrethrin, it causes paralysis and leads to death.
While this insecticide is toxic to small household pests, it isn’t toxic to people or larger animals like dogs. Cats can be harmed by this chemical, so use caution.
The application process of permethrin is the same as pyrethrin. Mix with water, shake thoroughly, and apply to problem areas of your home (or outside, too).
Permethrin SFR is a top product that contains permethrins.
3 Bonus Remedies to Get Rid of Silverfish Outside Your Home
One way to keep a silverfish problem out of your house is to use clear silicone caulk around all the cracks and crevices on the outside of the house.
Using a standard caulk gun, go around the outside of the house sealing any crack and crevice no matter how small.
Pay close attention to the foundation. If your house is on a concrete slab, put the caulk on the joint between the concrete and the wood, all the way around the house.
If your home is brick, there will be a lot of gaps around the windows, plumbing, and electrical intrusions.
If your house is a pier-and-beam, you’ll have to put on some coveralls and crawl under it to seal all the cracks and crevices from below. Be sure to take a flashlight so you can see what you’re doing.
Caulking is a slow process, don’t try to rush it.
If you do the job properly, caulking the house will take several hours and at least 3-4 tubes of caulk, possibly more. Once you’re done though, silverfish and most other insects will be locked out of the house.
Another method that may work is sticky traps. Place sticky traps in all the areas where you’re seeing silverfish.
Pay close attention to the areas of high humidity, though. Sticky traps are thick paper or thin cardboard; exposure to humid conditions or water will cause them to become soggy and useless.
In dry areas, sticky traps can be left out until they are full of bugs, but in humid, damp, or wet areas, they should be checked every 3-4 days and changed as needed.
An easy DIY sticky jar trap involves a glass jar and masking tape (as well as some bait inside the jar).
Wrap masking tape around the outside of the jar, so the silverfish are able to climb up. When they fall in the jar, they won’t be able to get back out because the glass is too smooth for them to grip.
This is another natural remedy that can get rid of silverfish, as well as other household pests like cockroaches. It even kills pests like fungi and weeds.
Boric acid is typically combined with another pesticide or chemical to improve its efficacy, which is why we don’t consider it a “natural” remedy in the same sense as lavender oil or cinnamon sticks.
Boric acid comes in a number of different forms, like liquids, granules, powder, and bait. It can be applied to pretty much anywhere, from your yard to your gutters to your kitchen cabinets.
How you apply boric acid depends on what form the product comes in and where you’re applying it indoors or out.
A reliable and popular brand of boric acid is Borax.
Best Product Suggestion for Getting Rid of Silverfish
Suspend is one of the best pyrethrin-based pesticides on the market today. It has little to no odor even when it is mixed at double strength. In addition to silverfish, it kills a wide range of other insects such as ants, spiders, and beetles.
It can be used outside as well as inside, which means you can use it around the outside of the house to keep silverfish from invading your home in the first place.
Once applied, it dries quickly and leaves an invisible residue that continues to kill bugs for up to 90 days before it biodegrades down to zero. At that point, you’ll have to reapply it.
It is also one of the safest pesticides on the market. You, your children, and pets will all be perfectly safe with Suspend. It kills the bugs and doesn’t even bother you.
How to Prevent Silverfish in the First Place
One of the best ways to prevent silverfish from entering your house is to make it uninviting to them.
Chief on the list is to dehumidify your house. This won’t be a major issue in the winter, but in the warmer weather, it will make a huge difference.
Get a dehumidifier and watch the change. Any silverfish in the house will make a beeline out of it, and any outside will turn around and leave as soon as they detect the low humidity in your home.
Keep all the food in the pantry in airtight containers. That way it won’t release any odors to attract silverfish and other pests. Wipe up any spills as soon as they happen and keep the kitchen and bathroom counters clean and dry.
Keep books and paper off the floor. Silverfish love paper and cellulose products. If there is anything on the floor they’ll find it and be right at home. If it’s up on a shelf they’ll be less likely to run into it.
Wrapping Up: How to Get Rid of Silverfish
Silverfish aren’t a terrible pest like bed bugs or wasps, but they are creepy nuisances. No one wants bugs in their home; we’ve given you a whole range of ideas you can use to kill them or keep them out.
For the most part, we prefer a multi-layered approach. Combine several of the methods we’ve listed to create overlapping layers of defense. That way, if one doesn’t get them, the other one will. Bye-bye, bugs!
Other Silverfish Guides
Curious about other silverfish articles? Check out our other detailed guides to help you deal with your pest problems.