Why Are There So Many Stink Bugs In My House?
Brush up on stink bug basics and learn how to get rid of these smelly home invaders.
Stink bugs feel like nature’s revenge for every insect you’ve ever squished. They get their name from the foul stench they release when they’re threatened or disturbed. It’s a smell that’s tough to describe. Chemically it contains compounds found in cilantro, but the odor is stronger, with notes of dirty socks, rotting fruit and paper-mill pulp. In short, it stinks — and worse, it lingers.
Seasonal cues trigger stink bugs' search for winter quarters; the shortening days and falling temperatures sending them scuttling for cover. If they sheltered beneath tree bark or mulch, it would be one thing. But they prefer sharing your home over winter, piling into cracks and crevices by the thousands. Researchers once found 4,000 in a bread box size container — and 30,000 inside an outhouse-size building.
Stink Bugs Indoors
Once stink bugs hide indoors, they stage a slow-motion home invasion all winter long. They’re intrepid explorers, lumbering along any surface — countertop, couch, toaster or bed. They like warm places, which means they’re happy to jump into your shower or morning coffee. When they fly, they bump and blunder into things, sounding like helicopters with serious mechanical issues.
The reason for a stink bug’s disoriented behavior indoors is diapause, a sort of insect hibernation. This zombie-like state allows them to move, just not with much finesse. They typically appear when a winter warm spell fools them into thinking it’s spring. Instead of finding their way outdoors, they emerge in your living spaces — and chaos ensues.
The good news is that they don’t eat, bite or reproduce indoors. Like Yankee snowbirds flocking to southern shores, they’re just overwintering. When spring arrives, they’ll head outside to kick off a new season of munching and mating. The bad news is that if you spot a few, there's likely an army waiting to march into view, one at a time.
How To Deal With Stink Bugs
Inside, stink bugs tend to congregate on upper floors and in tight spaces. That’s why they often tuck into drapery folds and walk along the tops of walls. It’s why they mass in attics and crawl spaces above garages. So what do you do when you spot a stink bug on the move inside? It’s best to deal with them one by one. Try one of these techniques.
- Soapy water. A stink bug’s natural reaction to any perceived threat is to drop straight down. Fill a wide mouth jar with soapy water (add some vinegar for extra killing power), move it into position beneath a stink bug, and most often it will drop right into the suds and drown.
- Sticky pad. Cover a dry sweep mophead with a sticky lint remover sheet, and use it as a long-handled stink bug catcher. It’s perfect for grabbing any high-climbing bugs.
- Night light. Before bed, fill a wide pan with soapy water and place it in the room with the most stink bugs. Place a small light so it hangs over the dish. Overnight the stink bugs will flock to the light, fall into the suds and drown.
- Vac. For bad infestations, some homeowners buy a small shop vac dedicated for stink bug use. Each time you use the vac, empty it into a bag you can seal. Stink bugs have been known to crawl out of vacuum cleaners.
- Avoid sprays. It’s tempting to douse the stinkers with an all-purpose insecticide, but few actually work to kill these bugs (they often raise from the dead a few days later). Also, if you do manage to kill them, their bodies may attract other insects to feed on them.
How To Keep Stink Bugs Out
Stink bugs typically gather on warm, west-facing walls and enter buildings via cracks and crevices. Once they find an ideal spot, they release pheromones, chemical signals that beckon more stink bugs to join the party. Your best bet is to keep them out, here are some tips and tricks.
- Block points of entry. Use caulking to replace cracked seals around utility entry points, doors and windows. Inspect joints where two different materials meet, like wood and concrete block or wood siding and brick. Caulk the cracks as needed.
- Check doors. Look over weather stripping and sweeps on doors, including the rubber seal on garage doors. Replace as needed.
- Inspect screens. Check for holes and patch as needed. Make sure the screens fit tightly into their space. Rub screens with dryer sheets — some homeowners say it works to keep the bugs from blanketing screens.
- Squish some. Some homeowners report that if they squish a few stink bugs where they start to gather, it seems to repel other ones. Some folks even whip up a stink bug spray (stink bugs and water in a blender, strain out any solids) that, when sprayed on a home, seems to help deter the bugs.