Spiders in the Basement? Here’s Why They Show Up in September

September rolls around in Missouri and, like clockwork, you start spotting more and more spiders—especially in the basement. If you’ve noticed a few extra legs lurking in the corners lately, you’re not alone. At Vogelsang Pest Management, we get a spike in calls this time of year from homeowners in the O’Fallon area wondering what’s going on.

Let’s break down why spiders seem to come out of hiding in the fall—and what you can do to keep them from turning your basement into their new hangout.

Why Are There So Many Spiders in Missouri?

Missouri’s warm, humid summers followed by cooler, drier falls create the perfect environment for spiders to thrive. We’ve got a wide range of species here—from common house spiders that are more nuisance than threat, to the more concerning ones like the brown recluse and black widow. And just like us, spiders prefer to stay warm and dry as the seasons change. That’s why your cozy basement starts looking like prime real estate.

Why Do Spiders Love Basements?

1. It’s Dark and Quiet: Spiders are naturally drawn to dark, undisturbed spaces where they can spin their webs in peace. Basements often stay dim and see little foot traffic, making them an ideal spot for these critters to settle in. Adding better lighting and checking in on your basement more regularly can make it less appealing to them.
2. There’s Clutter to Hide In: Stacks of boxes, storage tubs, and forgotten holiday decorations give spiders plenty of cover to hide, nest, and lay eggs. The more cluttered your basement is, the more likely it is to become a spider hotspot. Keeping things organized and switching to sealed plastic bins instead of open cardboard can make a big difference.
3. They Follow Other Bugs In: Spiders are hunters, so if your basement has flies, silverfish, or other small insects, it’s likely that spiders will show up looking for a meal. Reducing excess moisture and sealing cracks or gaps in your foundation can help block entry points—not just for spiders, but also for the bugs they feed on.
4. It’s Mating Season: Fall is peak mating time for many spider species, so you’ll see more of them out and about as males start wandering in search of a mate. Mating season and the cooler weather often lead them straight into homes through tiny gaps around doors, windows, and vents. Installing door sweeps and checking your screens for tears can help keep them out before they settle in.

Know Your Missouri Spiders

Understanding which spiders you’re dealing with is the first step to solving the problem. Harmless species like the common house spider are annoying but not dangerous. However, venomous spiders like the brown recluse and black widow are a different story. Both are found in Missouri and prefer quiet, undisturbed areas—again, basements are prime territory.

Their bites can cause serious health issues, especially for children, pets, and the elderly. Even though these spiders aren’t aggressive, it’s still unsettling to know they’re around. And let’s be honest—nobody wants to be surprised by one in the laundry room.

Keeping your home clean, clutter-free, and well-sealed goes a long way in reducing spider populations. But if you’re already seeing webs in the corners or spotting the spiders themselves, it’s time to call in the pros.

Let Vogelsang Handle It

At Vogelsang Pest Management, we offer custom spider control programs designed for homes and businesses right here in the O’Fallon area. Our team will:

• Perform a comprehensive inspection to identify where spiders are hiding and how they’re getting in
• Safely remove existing spiders and webs
• Apply targeted treatments to create a protective barrier around your home or business to stop future infestations.

We’re a local, family-owned business that understands the unique pest challenges of Missouri living—and we’re here to help you enjoy a spider-free fall.

Tired of sharing your basement? Give Vogelsang Pest Management a call today, and let’s kick those creepy crawlies to the curb.