Shiny red ladybugs with black polka dots are adorable, but if they want to congregate inside your house? Not so cute.
But while you may not want them indoors, they’re actually good to have around— and their numbers are in decline.
“They’re a gardener’s best friend because they’re voracious predators,” says Mary Gardiner, PhD, professor of entomology at Ohio State University. “And while most people know bees are in peril, many native lady beetles are threatened, too, due to pesticides, urbanization, and competition from non-native species.”
In fact, ladybugs are not even true bugs at all—which is why some experts call them lady beetles instead.
“The term ‘bug’ generally refers to insects that have piercing-sucking mouthparts and may feed on plants,” says Lauren Diepenbrock, associate professor entomology at the University of Florida.
Beetles (including ladybugs) have chewing mouthparts.
These beetles—while annoying indoors—are helpful for devouring large number of pests that attack crops and ornamental plants.
“Both native and non-native lady beetles are great predators of most things soft and squishy such as aphids, scales, mealybugs and whiteflies,” says Diepenbrock.
There are many different species of ladybugs, so you may see lady beetles ranging in color from orange to yellow to red. You'll see them with and without spots, as well. Not all species want to winter indoors.
Here's what else you need to know about ladybugs and how to get rid of them if they head indoors:
Are Ladybugs Dangerous?
Lady beetles are only a mild nuisance indoors. They don’t carry disease or infest wood, like termites. They won't get into your food or destroy cloth like pantry or clothes moths. And they don’t reproduce indoors.
Pets usually don’t bother them because the insects excrete hemolymph (blood), which has a funky taste, says Diepenbrock. This smelly yellowish fluid is released as a defense mechanism from their joints when they are disturbed. But it's not difficult to clean up with soap and water.
Lady beetles can bite, but only if threatened, and it feels like a pinprick. However, some people do develop an allergy to their frass, or poop, says Diepenbrock.
Why Do I Have Ladybugs in My House?
Adult lady beetles often come indoors looking for a sheltered place to spend the winter, says Gardiner. They go into diapause, sort of like hibernation, during this time before emerging in spring, to mate.
Sometimes they’re active on sunny days, which is why you may see them flying around or hanging out on your windowsills on a mild mid-winter day.
However, not all species want to spend winter inside your home. Native ladybugs prefer to winter outdoors. But the most common type that comes indoors is the non-native Harmonia axyridis, the multi-colored Asian lady beetle, also known as the harlequin beetle.
This species winters in light-colored cliffs in their native range so it’s attracted to the sunny side of your house, especially if it’s light-colored, says Gardiner. From there, it’s easy for them to slip indoors through tiny openings.
How to Get Rid of Ladybugs
Preventing entry is the best way to keep Asian lady beetles, or harlequin beetles, from becoming a nuisance indoors, says Gardiner.
Lady beetles are tiny and can fit through any hole or crack as small as 1/8-inch in size. Start your preparations in late summer before freezing temperatures arrive and the insects start looking for a place to hide out for the winter.
You won’t be able to prevent every lady beetle from entering your home, but these steps may reduce their numbers:
- Check the weatherstripping around windows and doors. Seal cracks where different materials meet, such as brick and wood siding, with caulk.
- Use expanding foam to fill crevices around pipes and wires entering the house.
- Repair damaged screens.
- Install door sweeps or thresholds on exterior doors.
- Add a rubber seal along the bottom of garage doors.
If you do find lady beetles indoors, simply vacuum them up, says Gardiner. They’re not killed by vacuums, so you’ll need to dispose of the bag (or they can escape or get smelly, if you’ve vacuumed up a large number), or drown them in soapy water.
Can I Buy Ladybugs to Release in My Garden?
While it's possible to buy live ladybugs online, Gardiner doesn't recommend the practice.
“These are usually a species called Hippodamia convergens, or convergent lady beetles, which pile up together when in diapause,” she says. “They are wild-collected and scooped up from these big piles, then shipped.”
Not only does this practice redistribute species that may not be well-suited to your environment, they may pass diseases or die en route. They also typically wake up and fly off because they have a natural tendency to disperse away from release sites, says Gardiner.
The best way to support a healthy population of lady beetles, according to Gardiner? Avoid using pesticides in your garden and plant a wide variety of flowers that pollinators like.
Lady beetles need flowers with accessible nectar, so look for those that are wide and flat or open. Lady beetles have no special mouth parts to access flowers, and this makes nectar easier to get to.
Good options include both annuals and perennials such as marigolds, calendula, lantana, asters, yarrow, and coneflower.
Arricca Elin SanSone has written about health and lifestyle topics for Prevention, Country Living, Woman's Day, and more. She’s passionate about gardening, baking, reading, and spending time with the people and dogs she loves.
