How to get rid of ladybugs in your house (and keep them out next fall)

Step by step: how to get rid of ladybugs in your house

1. 1

   Check that they are Asian lady beetles

   The ladybugs that pile into houses in fall are almost always multicolored Asian lady beetles. They are about 1/4 inch long, tan to orange to red, with anywhere from many spots to none, and most have a dark M or W shape on the whitish area behind the head.

2. 2

   Vacuum them, do not swat or sweep

   When disturbed, the beetles release a smelly yellowish fluid from their leg joints that stains walls, curtains and fabric. Vacuuming is the cleanest way to remove them. Sweeping or swatting makes them release more of it.

3. 3

   Put a stocking in the hose

   Push a nylon knee-high stocking into the vacuum hose and fold the top over the end with a rubber band. The beetles collect in the stocking, which you can tie off and throw away or empty outside. With a bagged vacuum, take the bag out right after and seal or freeze it so the beetles do not crawl back out.

4. 4

   Find where they are getting in

   On a sunny fall afternoon, watch the sunny southwest side of the house, where they gather first. Indoors, look at window and door trim, baseboards, light fixtures, ceiling fans and exhaust fans; beetles that show up inside in late winter are usually coming out of wall voids and attics.

5. 5

   Seal cracks and gaps

   Caulk cracks around window and door frames, siding, soffits, fascia boards and where pipes and wires enter. Plug larger holes with copper mesh or foam. University of Kentucky entomologists note that gaps of 1/8 inch or less will still let lady beetles in, so a tight seal matters.

6. 6

   Fix screens, vents and door gaps

   Repair torn window screens, put screening behind attic and soffit vents, and install door sweeps on exterior doors. Seal gaps under sliding doors with foam weather stripping. These same fixes also keep out flies, spiders and crickets.

7. 7

   Clean up stains and the smell

   Blot yellow stains with a cloth and a little warm water and dish soap; do not rub, which spreads them. Vacuum dead beetles from windowsills, light fixtures and attics, since the bodies smell and can feed carpet beetles that later damage wool and stored goods.

Why are ladybugs coming into your house?

They are looking for a protected place to spend the winter, and the cracks, wall voids and attics of a house suit them well.

According to the University of Kentucky’s fact sheet on Asian lady beetle infestations, the beetles fly to buildings from September through November, with flights heaviest on sunny afternoons after a cool spell, when temperatures climb back to at least the mid-60s. They are drawn to sunlit, southwest-facing walls and to contrasting light and dark features, such as dark shutters on light siding. Homes near woods or fields tend to get more. The same source notes that they do not reproduce indoors: the beetles you see in late winter are the same ones that came in during the fall, now trying to get back outside.

Should you spray or bug-bomb for ladybugs?

No. Indoor sprays and foggers do not reach the beetles hiding in walls and attics, and they leave residue and stains on surfaces where you live.

Penn State Extension advises against insecticides once beetles are in wall voids or attics, because thousands of dead beetles can then feed carpet beetles that move on to woolens and stored foods. Penn State recommends vacuuming the beetles indoors and sealing the cracks where they emerge, and notes that the beetles are attracted to light coming through cracks in walls and ceilings. As a temporary fix, tape over the cracks in the rooms where you see the most.

If you get large numbers every year and sealing is impractical, for example on a tall house, a licensed pest control company can apply a targeted exterior treatment around windows, eaves and soffits in early fall, just before the beetles arrive. Any pesticide product should be used strictly by its label, with children and pets kept away until it dries.

Are ladybugs in the house harmful?

They are mostly a nuisance. They do not eat wood, food or clothing, and they do not breed indoors.

• They can pinch. The bite feels like a pinprick and is rarely serious.
• Some people are allergic to them. The University of Kentucky fact sheet reports reactions ranging from eye irritation to asthma; wash your hands after handling them and see a doctor if you react.
• Their yellow fluid stains and smells. Clemson’s Home and Garden Information Center says to vacuum them as soon as possible because a few can attract others, and to empty the vacuum bag right away, since beetles left inside can crawl out or die and produce a foul odor after a few days.

For other fall invaders that come in through the same gaps, see our guides to spiders and earwigs.

Mistakes to avoid

• Sweeping or crushing the beetles, which smears yellow stains on walls and floors.
• Leaving a full vacuum bag inside, where the beetles crawl back out or rot and smell.
• Setting off a bug bomb, which does not reach the beetles in walls and leaves residue.
• Waiting until October to seal the house; the work belongs in late spring or summer.
• Leaving dead beetles in the attic, where they feed carpet beetles.