How to Keep Insects Out of Your Home
Beat the fall bug invasion with these simple, non-chemical tricks.
I had my first encounter with stinkbug hordes on a lovely fall day at a rest stop in Western Maryland. Stinkbugs blanketed building walls, benches and parking signs. I thought surfaces were sprouting graffiti until I realized the dark color was moving. I could not get back into my car without handfuls of the stinky critters following me. It was horrible.
These bug gatherings are an instinctual response to seasonal cues. Shorter days and falling temperatures signal insects to start the search for winter quarters. In the wild, these critters nestle into cozy spots beneath leaves, bark or rocks. In your yard, space beneath siding or inside wall voids looks like the ideal place to hide out for winter.
When insects form a flash mob the back wall of your home, it’s tough not to panic. No one wants to share housekeeping with a horde of Asian lady beetles, box elder bugs or tule ground beetles. In some cases, you may not be able to do anything to keep the bugs at bay. For instance, a light colored west-facing wall is the equivalent of insect heaven, thanks to its warming effect on cold bug bodies. But even in that case, you can beat the bugs. Check out steps you can take to keep your home pest-free for winter.
Block the Way Inside
The No. 1 thing you can do to keep insects out of your home is to block points of entry. Grab a caulking gun and replace any cracked seals around windows, doors and utility service entry points. Check weather stripping and sweeps on doors, replacing as needed. Double-check window screens, and make sure they fit snugly. Repair holes with a patch kit. Above all, don’t leave doors standing open, especially the big door on an attached garage. Most often insects enter a house just like you — by walking through a door.
Limit Outside Habitat
Tend to areas surrounding your home to downgrade the bug friendliness and eliminate hiding places for insects.
- Walk around the outside of your home looking for potential bug shelters. Things like leaf litter, logs, bricks and abandoned summer container gardens all provide potential hiding places for insects.
- Keep window wells clear of weeds and autumn leaves. If your property sees a lot of fall leaves, consider investing in window well covers.
- Avoid direct contact between planting beds, mulch and the walls of your home. A 6- to 8-inch space between mulch and walls is ideal. If planting beds abut your house, trim shrubs and pull weeds to maintain a plant-free zone. All it takes is one leaf touching your home to provide easy access for insects.
- Reduce mulch thickness to maintain a 3-inch layer. Thicker layers provide ideal harbor for insects like millipedes or pill bugs, which tend to show up in basements.
- Remove host plants that attract specific congregating insects. I once had a honeysuckle hedge that was always full of aphids and thus a prime habitat for Asian lady beetles. Needless to say, we dealt with overwintering lady beetles inside. You might face elm leaf beetles thanks to elm trees or box elder bugs hanging out on silver maples and female box elders. It’s a big step to take down established hedges or trees, but sometimes it’s the best solution to a severe pest issue.
Other Steps You Can Take
A few other simple actions that help reduce the chances of insects finding their way inside include:
- Arrange downspouts to send water away from your foundation. Insects need moisture to survive and prefer damp locations. Properly arranged downspouts keep a foundation dry.
- Store firewood outdoors. Only bring in what you need to burn. Otherwise, warm temps indoors can coax all kinds of overwintering insects out of wood.
- Turn off outside lights during the early part of autumn, when insects are gathering. This is a successful control for crickets that tend to move in darkness.
If you encounter an insect — indoors or out — that you don’t recognize, get help identifying it at a local plant diagnostic clinic.
If Bugs Do Appear
In the dead of winter, a warm snap can wake up sleepy bugs. As warmth builds inside your home’s walls or attic, insects think spring has sprung and wander out of hiding. Unfortunately, instead of crawling outside, they invade your living spaces.
It’s tough to stay calm dodging helicoptering stinkbugs in the middle of winter. (I run from the room screaming when they divebomb.) When insects appear, the right response is to take steps to deal with pests one by one. Avoid using indoor sprays for a blanket kill, or you risk killing bugs that are still hiding. You don’t want dead insects in your wall voids, because other insects will come to feed on them. That’s the stuff of nightmares.
Take heart. These pests aren’t reproducing in your home. They’re just hanging out until spring really arrives — and then they’ll head outside to find mates, reproduce and do their bug thing.