Why Are There So Many Ladybugs in My House?

Ladybugs, ladybeetles, ladybirds. Whatever you call them, these glossy, colorful beetles are a beautiful sight to behold — when they’re outside. But when a ladybug plague of biblical proportions takes up residence in your home, the insects lose their distinctive charm. If you’re asking yourself, “Why are there so many ladybugs in my house?” you’ve come to the right place. 

Why Ladybugs Come Indoors 

Ladybugs typically enter people’s houses in fall and winter when the weather starts getting cool. Seeking warmth, they make their way inside through basements, drainage pipes and cracks around windows and doors. 

The insects then emit a pheromone that attracts other ladybugs to join them. It’s a kind of chemical signal that lets other insects know they’ve found a safe place to rest, which is why you’ll often find hundreds of ladybugs in your house at the same time. 

Ladybugs can travel in swarms up to several million strong, with one group of ladybirds in California making the news in 2019 when meteorologists saw it on the radar. The swarm was 80 miles long and 80 miles wide. 

If you didn’t have such an inviting home, traveling groups of ladybugs would normally brave the cold inside a crevice, fallen log or hollow tree, toughing out the winter weather by huddling up en masse until spring. But your house is cozier than a rotting log — well, hopefully, anyway — and the ladybirds have good taste. So, what can you do?

How to Get Rid of Ladybugs

First, it’s important to note that ladybugs are typically beneficial insects, especially if you like to garden. Their main cuisine is aphids, tiny, destructive pests that love to eat your prize-winning cabbage. That’s reason number one not to kill the ladybugs in your house.

Reason number two is that they tend to stink when you squash them. Injured ladybirds release a chemical called pyrazine with an odor akin to moldy vegetables, which is almost worse than dealing with an infestation itself. 

Pyrazine’s role is to startle predators and warn them that ladybugs taste terrible. In fact, ladybugs are so pungent that winemakers have to avoid crushing them in their grapes by mistake, lest the wine be affected with the unfortunately named ladybug taint. According to sommeliers, ladybug-tainted wine has notes of bell peppers, burned peanut butter and straight-up dirt. It seems dead beetles don’t pair well with Sauvignon. 

Lastly, squishing ladybugs can stain your walls and carpeting a sickly yellow. Unless you want to repaint your interior in Behr’s new “Ladybug Juice” line of fall colors — which doesn’t seem to be trending — then suppress the urge to stomp. Here’s what to do instead:

1. Sweep Them Up

Ladybugs tend to be slow-moving or even die once inside your home. The interior of a house is usually drier than the insects prefer, and you probably don’t have aphids in your home for them to eat, either. Consequently, it’s pretty easy to sweep ladybugs from hard floors and tables with a broom. Take them outside and dump them as far as possible from your house. 

2. Break Out the Vacuum

If the broom isn’t cutting it — or the ladybugs have congregated in the corners and along the walls — then using a vacuum cleaner should help. Use the nozzle to suck the ladybugs up, then dump them outside as far from your house as possible. Just be aware that your vacuum might not smell great after this process, so you should probably replace the bag before doing any further housekeeping. 

3. Winterize Your House

Why are there so many ladybugs in your house to begin with? In all likelihood, they found a small crack to squeeze their way through. If so, you’re probably spending extra money heating your home, and with winter approaching, it’s a good time to insulate your house. 

Add weather stripping and caulk around all your windows and doors. The added insulation should prevent cold drafts and ladybugs from finding their way in. And, as a bonus, your energy bill should be lower. 

4. Use Natural Repellents

Like many people, ladybugs seem to dislike the strong smell of citronella, but you can also employ the soothing scent of peppermint, bay leaves, citrus or cloves to keep the bugs at bay. They reportedly also dislike mums — the flowers, that is — so you can use the plants both to decorate your home for fall and repel ladybugs. Plant them in pots or use vases of mums in strategic locations, like near your doorways. 

5. Remove Pheromones

To keep ladybugs from coming back, you’ll need to remove all traces of the pheromones they left in your house. Otherwise, the lingering smell may keep attracting ladybugs, and you’ll be caught in a cycle of sweeping and washing up after your uninvited houseguests. Use regular household cleaning products or a vinegar-and-water solution to clean up the scene of the swarm. 

6. Call an Exterminator

If the ladybird problem is impossible to manage on your own, call an exterminator only as a last resort. This can also be a good option if you’re dealing with more than one type of infestation. 

You’ll probably need to spend a couple of nights in a hotel as your house is fumigated. Keep in mind that once the ladybugs die, you should always throw them in the trash, since dumping a pile of poisoned insects outside is far from environmentally friendly — the toxin could harm wildlife or end up in the water. Clean your house thoroughly after the fumigation process. 

Why Are There So Many Ladybugs in My House?

To sum it up, the reason there are so many ladybugs in your house is likely that they’re looking for warmth. In certain parts of the U.S., ladybugs congregate in swarms when cold weather is approaching, and your house is a cozy, inviting place for them to land. 

You can minimize the number of beetles in your house by sweeping them up and improving the insulation around your windows and doors. However, you can take comfort in knowing winter is just around the corner, so the ladybugs should be gone very soon no matter what you do. Just keep the vacuum on hand.