Some spiders are harmless, while others can be dangerous, so keeping them out of your basement (and home in general) is essential. Read on to discover some of the most effective strategies to keep spiders out of your basement.
Table of Contents
1. Seal all openings
For spiders to infest your basement, they must first get inside. Reduce the likelihood of this occurring by sealing up every nook and cranny they may use as entry points. Use caulk to fill in cracks, holes, and gaps in the walls, doors, and windows. You’ll also want to apply caulk around cables, faucets, wires, and electrical components since all these must connect to the outside.
Windows are a prime entry point for spiders, so make sure to fix or replace old window screens with well-fitting fine mesh. If there are gaps too wide for caulk, opt to use expanding foam, which will serve much of the same purpose. You’ll also want to cover the vents in your basement with fine mesh insect screens.
2. Get rid of other pests
One of the main reasons why you may have a spider-infested basement on your hands is the presence of other pests. Food is a key attractant for spiders, and pests like roaches, mosquitoes, and termites are all spider prey. Therefore, getting rid of these insects will make spiders less inclined to stay in your basement. Some tips to get rid of pests include:
- Keep your outdoor lights off – While outdoor lights don’t attract spiders, they will attract other pests that can potentially become spider prey. You can keep your outdoor lights, or block indoor lights from filtering through your basement windows by using opaque shades or blinds. Alternatively, consider switching to yellow sodium vapor lights. These types of lights are less likely to attract insects, which means fewer food sources for spiders.
- Remove overgrown vegetation – Overgrown trees, shrubs, and other plants are great hiding spots for pests, so you might want to clear them from the perimeter of your home or transplant them to the opposite side of the yard. You should also remove stones, leaves, mulch, or other debris near your home.
- Cover your pet food – Make sure you keep pet food well covered when not in use to prevent attracting flies and insects, which will, in turn, draw in spiders.
- Move your bins – Spiders eat flies and flies flock to garbage bins, so make a point of keeping them a couple of feet from your home if possible. The bins should especially be kept away from your basement windows to prevent these critters from crawling into your home.
- Take your recycling out as often as possible – Fizzy drinks in bottles or leftover food in packages can attract flies, and in turn, spiders. In addition, empty bottles and food containers can make good homes for spiders, so make sure you empty your recycling regularly.
- Apply a residual insecticide – Consider applying a residual pesticide to get rid of the pests that spiders might feed on. Choose a pesticide that you can safely use indoors and then spray it around your basement. You’ll want to target the corners and crevices, which is where these critters will likely be hiding. Keep in mind that residual pesticides only work if the pests come in contact with the chemical after it’s sprayed. If that doesn’t happen, the insecticide will not affect them. As with any other pesticides, read the instructions marked on the label to avoid accidentally poisoning a child or pet.
3. Declutter your basement
Spiders prefer to live in cluttered places, so if you have a disorganized basement, you might find that you have a spider problem. You have to clean and declutter your basement to prevent this – there’s no way around it.
Get rid of anything you don’t need or hold a yard sale and sell them off. Store your things away from your basement walls to discourage spiders from forming spider webs and building nests on them. You might also want to consider investing in a plastic organization or container boxes instead of standard cardboard boxes – these are prone to cockroach attacks.
4. Avoid stacking wood inside
Spiders such as black widows thrive underneath woodpiles, probably because they attract insects that they can feed on. So if you stack wood in your basement, it’s time to find other storage options, like your backyard. Ideally, you’ll want to keep the wood a couple of feet from your house to discourage spiders from finding their way back inside. If you’re worried about the wood getting soaked, consider building a tool shed to keep them safe and dry.
5. Vacuum spiders and spider webs
An easy way to get rid of spiders is to vacuum up webs and egg sacs that you come across in your basement. This method is ideal for when you’re trying to get rid of a few spiders. It may not be as effective if you have a significant spider population in your home, however.
After you finish vacuuming, remember to empty it first. If you leave the vacuum canister or bag as is, it’s possible for baby spiders to hatch from the eggs you vacuumed and crawl right back into the cracks and crevices of your home.
6. Spray the basement down with peppermint oil
If you don’t want to apply a residual pesticide to your basement, consider peppermint oil instead. Fill a spray bottle with water and mix in around 20 drops of peppermint oil. If you don’t have peppermint oil (or you don’t like its smell), you can use tea tree oil, eucalyptus oil, or lemon oil in its place. Spray all the dark corners of the basement and potential entry points with this solution. Dab undiluted peppermint oil (or your preferred essential oil) onto several cotton balls and strategically stuff them into cracks and other possible hiding spots for more potency.
7. Spread diatomaceous earth in the basement
Diatomaceous earth is a chalk-like powder that is made from fossilized algae sediment known as diatoms. This substance effectively kills spiders because it contains silica particles with sharp edges that resemble broken glass when examined under a microscope. These edges can cut through a spider’s exoskeleton, leading to absorption of the diatomaceous earth by the spider’s body moisture, causing it to dehydrate and die. When purchasing diatomaceous earth, make sure to go for the food-grade variety rather than the type used for pool maintenance – the latter is highly toxic.
- Kills a Variety of Insects - Kills roaches, fleas, ants, bed bugs, and more
Here are some guidelines on how to apply diatomaceous earth:
- Apply a thin layer of diatomaceous earth along cracks, crevices, and other spider hiding spots. If you come across a large group of spiders, try spreading the powder directly over them and create a perimeter around them.
- In hard-to-reach areas, use a duster to spread the diatomaceous earth.
- Wait 24-48 hours – you might see results in as little as a day or two. Apply a follow-up treatment if needed.
- If the spiders have gone, clean up the diatomaceous earth and carefully wash the surfaces where the spiders have been to get rid of the pheromones that will attract more spiders.
While diatomaceous earth is an effective spider killer, it will typically only kill a small portion of a spider infestation.
8. Use a white vinegar spray
Even though white vinegar has a distinct pungent smell, this is not what deters spiders. White vinegar contains acetic acid that kills spiders on contact. To make a white vinegar spray, mix equal water and white vinegar parts in a spray bottle. Try to get as close as possible to the spiders before you spray for the best results. You can also spread the solution in areas where you’re likely to come across them (cabinets, closets, corners, etc.)Be sure to spray crevices and gaps in the floors and walls as well. Repeat as necessary.
A white vinegar spray can also be used to kill spider eggs. Spraying this solution directly on a spider’s egg sac will destroy it and all the eggs it contains. The egg sac is made of silk that white vinegar can dissolve, especially when sprayed close enough.
9. Citrus might just work
Another standard household product that you can use to get rid of spiders in your basement is citrus, such as orange and lemon. While citrus offers pleasant scents for humans, spiders find them overwhelmingly pungent and will scurry away when they detect them. There are a couple of ways you can use citrus fruits to your advantage. For starters, try placing orange or lemon peels near common hiding spots for spiders. Remember to replace them every few days. Another technique involves rubbing spider-infested areas with orange or lemon peels. This is an excellent option if you don’t want to leave peels lying around. The last option is to put some citrus oil in a spray bottle with some water, mix it up, and spray down the areas of your basement where spiders are likely to occur.
10. Garlic may repel spiders
Spiders detest the smell of garlic; depending on how intense a scent you can tolerate, either put crushed cloves or whole cloves into a spray bottle partially filled with water and use it to scent the floors, corners, crevices, and walls of the basement.
11. Repel spiders with cedar
Another smell that spiders can’t stand is cedar. This is because cedar emits phenols and natural acids that act as pesticides. Sprinkle cedar chips and blocks in your basement and around your home to get rid of spiders. A bonus is that the woody aroma is said to be effective in repelling clothes moths too.
12. Deterring spiders with horse chestnuts
A common belief is that placing piles of horse chestnuts strategically in your home will deter spiders. Although there is plenty of anecdotal evidence to support this theory, there is no scientific backing, with some experiments indicating that horse chestnuts didn’t make much impact on spiders’ habits.
The belief stems from the fact that the skin of the horse chestnut contains the bitter-tasting chemical compound saponin, which is a known natural insect repellent. There are a variety of natural insect repellents that contain extracts of plants with significant saponin levels, including horse chestnut extract. Supporters of this theory believe that spiders may be able to detect the pungent smell of saponin, which causes them distress or deters them from laying eggs in their vicinity.
13. Spray spiders with bleach solution
The high acidity of bleach makes it an effective household product for killing spiders. Here are guidelines on how to use it:
- Mix three parts water with one part bleach in a spray bottle
- Spray the solution directly on visible spiders at 6- to 10-inch range.
- Sweep up the dead spiders and toss them out. Wipe the bleach solution from the surface to prevent any bleaching effects.
- Spray the bleach solutions on areas of your basement where spiders tend to nest, hide, or enter the basement regularly to repel them.
14. Call a professional exterminator
If the methods above don’t work for you or notice potentially dangerous spiders in your basement, hiring a professional exterminator is your best solution. A professional will likely apply a stronger chemical pesticide that should get rid of the spider infestation in a timely fashion. Although this is probably the most effective way to eliminate spiders in your basement, it’s also going to be the most costly, so you may want to consider it as a last resort.
Once the spider infestation in your basement is under control, please take the necessary steps to keep them out of your home. You will need to do inspections and maintain regularly and apply repellents regularly to deter them.
Last update on 2023-04-16 / Affiliate links / Images from Amazon Product Advertising API