Spring Pests in St. Louis: What's Coming Into Your Home This Season (and How to Stop It)
Spring in St. Louis is beautiful — the dogwoods bloom, the parks fill up, and your windows finally open again after months of cold. But you're not the only one waking up. Ants are already scouting your kitchen. Termites are swarming near your foundation. Ticks are active in your backyard. And that brown recluse spider that spent the winter tucked inside your basement wall? It's on the move.
If you've ever felt like spring brings a sudden invasion of pests, you're not imagining it. The combination of warming temperatures, spring rains, and Missouri's humid climate creates the perfect conditions for a wave of pest activity — often all at once.
Here's what to expect this spring and what you can do before the problems start.
Ants: The First Wave
Ants are usually the first pests St. Louis homeowners notice in spring. As soon as temperatures climb into the 50s and 60s, scout ants emerge looking for food and water. If they find either one inside your home, they leave a chemical trail for the rest of the colony to follow.
Odorous house ants and pavement ants are the most common species in neighborhoods like Ballwin, Valley Park, and Florissant. They're not dangerous, but they're persistent — and store-bought sprays usually just scatter them rather than eliminate the colony. We've written about why ants show up even in clean homes, which is one of the most common questions we get every April.
Termites: Swarming Season Begins
Spring is when subterranean termites swarm to establish new colonies. In St. Louis, this typically happens on warm days following a spring rain — sometimes as early as March. You might notice small, winged insects near windows or doors, or find piles of discarded wings on your windowsill.
Missouri ranks among the higher-risk states for termite activity. The University of Missouri Extension's guide on ticks and pest insects notes that the state's warm, humid conditions make it especially hospitable to wood-destroying insects. If you spot swarmers in or near your home, don't wait — our termite service page explains the warning signs and treatment options in detail.
Spiders: Coming Out of Hiding
Spiders don't technically "come inside" in spring — many of them have been in your home all winter, living in undisturbed areas like basements, closets, and storage boxes. As temperatures warm, they become more active and start moving around to hunt for prey.
The brown recluse is the spider that worries most St. Louis homeowners, and for good reason. They're common in our area and their bites can cause serious tissue damage. The CDC's guidance on brown recluse safety recommends shaking out clothing and shoes that have been stored in dark areas, and using sticky traps to monitor for activity.
If you've found a brown recluse in your house — or you're not sure what you're looking at — we published a guide on how to identify them and what to do next.
Ticks and Mosquitoes: The Outdoor Threats
Tick activity in the St. Louis metro starts as early as March and peaks from April through July. The lone star tick is the most common species in Missouri and is linked to ehrlichiosis and alpha-gal syndrome, a condition that can cause an allergy to red meat. The EPA's guide to integrated pest management emphasizes that managing your yard environment — keeping grass short, removing leaf litter, creating buffer zones — is one of the most effective first steps in reducing tick populations around your home.
Mosquitoes follow close behind, becoming active once temperatures consistently reach 50°F. Standing water in gutters, flower pot saucers, and birdbaths can produce thousands of mosquitoes in a single season. Our mosquito control service provides monthly barrier treatments from March through October that target mosquitoes and ticks where they breed and rest on your property.
How to Get Ahead of Spring Pests
You don't have to wait until you see a problem. The most effective pest control starts before pests settle in. Here are the basics every St. Louis homeowner should cover this spring:
Seal cracks and gaps around doors, windows, pipes, and your foundation. Even small openings are highways for ants and spiders. Keep your kitchen clean — wipe down surfaces, store food in sealed containers, and take out trash regularly. Address moisture issues in your basement and crawl space. Pests of all kinds are drawn to damp environments. Trim vegetation and clear leaf litter away from your home's foundation. Schedule a professional inspection before peak season hits.
Here's How Pure Pest + Lawn Can Help
Schedule a free inspection. We assess your home's specific vulnerabilities — entry points, moisture conditions, yard layout — and identify any current pest activity.
We create a custom protection plan. Whether you need quarterly interior/exterior treatments, monthly tick and mosquito barrier applications, or a termite monitoring system, we build a plan around your home and your family's needs.
Enjoy a protected home all season. With a Pure Pest Plan providing year-round coverage, you can stop reacting to pest problems and start preventing them.
Pure Pest + Lawn has been protecting St. Louis families since 1933. We've earned the BBB Torch Award for Ethics and have over 1,000 five-star reviews — because we believe nobody should have to choose between living with pests and irresponsibly applied treatments. We strategically eliminate pests while protecting the people and pets in your home.
Spring is here. So are the pests. Call 314-222-PEST (7378) or schedule your free inspection online.
