Spiders are one of those household pests that seem to thrive in basements. All those dark, cool, and damp conditions are like a five-star resort for them. Spiders head down there looking for food, shelter, and moisture.
While most spiders are harmless, some, like the brown recluse and black widow, can pose a real threat. Knowing what kind of spider you’re dealing with is important to controlling them.
This guide gives you the lowdown on how to get rid of spiders from your basement, along with some easy tips and tricks to keep them from coming back. We’ll explore both natural and chemical methods, but our main focus will be on prevention.
Understanding Your Enemy: Identifying Common Basement Spiders
Before you launch an all-out assault on the spiders in your basement, it’s useful to know what you’re up against.
General Spider Characteristics
Spiders are arachnids, which means they have eight legs and two body segments. Most spiders have venom that helps them subdue their prey, but only a few species are harmful to humans. Spiders vary widely in size.
Identifying Dangerous Spider Species
It’s important to be able to recognize the two species of spiders that can cause serious harm to humans:
- Brown recluse spiders: These spiders are 1/3 to 1/2 inch long, and they have a violin-shaped marking on their backs. Their bite can cause serious tissue damage.
- Black widow spiders: The female of this species has a shiny black, globular abdomen with a red hourglass marking. Their venom is neurotoxic and can cause severe pain and muscle cramps.
Other Common Basement Spiders
Here are some of the other spiders you might find in your basement:
- Cellar spiders (daddy long legs): These spiders are often found in webs in corners and ceilings. They’re generally harmless to humans.
- Wolf spiders: These are large, hairy spiders that hunt on the ground. They can deliver a painful bite, but it’s not medically significant.
- Sac Spiders: According to Green Giant Pest Control, 90% of spider bite calls are for Sac Spiders.
Eliminating existing spiders: a multi-pronged approach
Once you’ve confirmed that spiders are indeed camping out in your basement, here’s how to get rid of them.
Removing webs and egg sacs
Grab your broom or vacuum and go after those webs and egg sacs! This will disrupt the spiders’ living space and may discourage them from sticking around. Pay special attention to corners, ceilings, and other out-of-the-way spots.
Reducing clutter
Spiders love clutter because it gives them places to hide. Try to cut down on piles of stuff in your basement, and store anything that’s down there in sealed containers. Get rid of cardboard boxes, which tend to attract pests.
Vacuuming thoroughly
Vacuuming those corners, cracks, and crevices is a great way to suck up spiders and their eggs. It’s a good idea to focus on the areas along the baseboards and around any pipes.
Using diatomaceous earth (DE)
Diatomaceous earth is a natural, nontoxic powder that can kill spiders by drying out their exoskeletons. Sprinkle it anywhere you think spiders might travel, like along baseboards, in cracks, and under appliances.
Applying commercial insecticide sprays
You can use a commercial insecticide spray to target spiders directly. Choose a spray that says it’s for spider control, and apply it anywhere you’ve seen spiders or think they might be hiding. For longer-term control, look for a residual insecticide that keeps working over time.
Deploying spider traps
Spider traps are like sticky flypaper for spiders. Put them in areas where you see a lot of spider activity. They’re easy to use and don’t require much upkeep.
Natural spider control: Harnessing the power of plants and oils
If you’re looking for ways to control the spider population in your basement without resorting to harsh chemicals, you may want to consider using the power of plants and essential oils.
Spider-repelling plants
Certain herbs and ornamental plants are known to deter spiders. Try planting some of these around your basement windows and foundation:
- Lavender
- Dill
- Marigolds
- Eucalyptus
Essential oils
You can also use essential oils to keep spiders away. Cedar, cinnamon, and peppermint oils are all effective. Green Giant Pest Control specifically recommends cedar and cinnamon oil.
To use peppermint oil, mix a few drops with water in a spray bottle and spray around entry points, corners, and other areas where spiders are likely to be.
Carnivorous plants
Carnivorous plants, such as pitcher plants and Venus flytraps, can help control spider populations. These plants trap and digest insects, including spiders. Place them near windows or other areas where spiders may enter.
Preventing future infestations: Sealing, cleaning, and moisture control
Once you’ve evicted your spider squatters, you’ll want to take steps to make sure they don’t come back. Here’s how.
Sealing cracks and crevices
Spiders often get into your basement through foundation cracks and gaps around windows and doors. Seal these openings with caulk or sealant to block their entry.
Reducing moisture levels
Spiders love damp environments, so reduce the moisture in your basement to make it less appealing. Use a dehumidifier to lower humidity and repair any leaks or plumbing issues.
Maintaining a clean and tidy basement
A cluttered basement provides hiding places for spiders. Regularly dust and vacuum to remove spider webs and eggs. Store items in sealed containers to prevent spiders from nesting inside.
Addressing the food source
Spiders eat insects, so controlling the insect population in and around your home is essential. Eliminate standing water to prevent mosquito breeding and use insect traps or sprays to control other pests.
Landscaping considerations
Your landscaping can inadvertently attract spiders. Keep shrubs and vegetation trimmed away from the foundation, and consider changing your outdoor lighting to reduce insect attraction, which in turn reduces spider attraction.
When to call a professional
Sometimes, you need reinforcements. A large or persistent infestation might need professional pest control. Pros have access to equipment and insecticides you can’t buy in a store.
If you think you have dangerous spiders, like brown recluses or black widows, definitely call an exterminator. They can identify and remove them safely. Also, if you’re uncomfortable handling insecticides yourself, a professional can give you effective and safe solutions.
Wrapping Up
Getting spiders out of your basement and keeping them out requires a two-pronged attack: elimination and prevention. By using the methods outlined in this guide, you can get spider populations under control and keep them that way.
Regular cleaning, decluttering, and controlling moisture are essential for preventing future infestations. In addition, sealing cracks and crevices in the foundation and using natural spider repellents can go a long way toward creating a spider-free zone.
With a little persistence and the right approach, you can create a basement that’s comfortable for you — and inhospitable to spiders. If you have a severe infestation or think you’re dealing with a dangerous species of spider, don’t hesitate to call a professional pest control service.