How to Get Rid of Ladybugs

So many homeowners can mark the coming of fall by an unwelcome visit from one the garden's most recognizable beneficial insects and perhaps hundreds of her friends.

Ladybugs will not harm your home, but that doesn't keep homeowners from seeking ways to get rid of ladybugs (also known as lady beetles) that aggregate on inside walls to escape the onset of cool weather and hibernate for the winter.

The interlopers are the Asian lady beetle (Harmonia axyridis), which were imported to the US from the 1960s to 1990s by federal, state, and private entomologists and released in an attempt to control insect pests such as aphids. Ladybugs, after all, are voracious predators.

Asian lady beetles can be identified by a small M or W, depending on how you look at them, on the shield-like section behind their head. Unlike the native lady beetle, the Asian species likes to aggregate inside to overwinter.

Why are There Ladybugs in My House?

The Asian lady beetles cluster inside your home for a very simple reason: to stay warm. This aggregation is triggered as the temperatures start to drop, so homeowners in northern states may notice the behavior sooner than the rest of the country.

The ladybugs are attracted to lighter areas that have a dark feature, such as a crevice or a crack in a southeast-facing wall or window illuminated by the fall sunlight, says Dr. Brian Forschler, a professor of entomology at the University of Georgia.

The ladybugs enter your home through these cracks, and when they find a comfortable spot to hang out for the winter, they leave a chemical marker behind that serves as a calling card for the rest of their friends. That's why homeowners will spot ladybugs gathering in the same location year after year.

Are Ladybugs Harmful?

Ladybugs won't damage your home or harm your pets. They don't eat wood and they are not disease carriers. They can bite you — what Dr. Forschler says would feel like a pinprick — but ladybugs are much better known and appreciated for the way they devour insect pests in the garden. An adult lady beetle is capable of eating up to 270 aphids per day.

Among the insects ladybugs feed on are aphids, mites, scales, thrips and white flies.

How to Get Rid of Ladybugs

While not harmful, they can be considered a nuisance if they gather indoors in large numbers. If agitated or disturbed, by a broom for example, ladybugs will release foul-smelling liquids — a defensive reaction known as "reflex bleeding" — that can stain drapes or clothes.

For this reason, Dr. Forschler says the best way to get rid of them is to vacuum them up and then dispose of them.

How to Keep Ladybugs Away

You could use either vinegar or ammonia-based cleaners to clean the spot where the ladybugs aggregated, removing the pheromones marking the ladybug's hangout. But to keep ladybugs from invading your home, you'll need to seal up the cracks through which they entered.

"Removing the pheromone might reduce the number that 'decide' to spend the winter at that site, (but) it probably won’t stop them as well as sealing the cracks and crevices on that side of the building," says Dr. Forschler.

That would mean caulking your home's exterior crevices and the cracks around doors and windows — and there likely are a lot of them. Maybe you and any of your houseguests just look the other way?

"Keeping them out is entirely possible, but hardly practical," says Dr. Forschler. "If you can convince people not to worry about (the ladybugs), that's huge."

If you have a serious infestation, call a professional pest control company for help.