Just Curious: What the Heck Do Ladybugs Eat, Anyway? (2024)

Few insects have built a massive fanbase like ladybugs. While these bugs are tiny, they’re pretty hard to miss as they pop up on T-shirts, backpacks, and just about anything they can hitch a ride on to brighten your day with their vibrant hue.

And because they’re so small, you might find yourself wondering: What do ladybugs eat, anyway?

Even entomologists (insect experts) totally get the fascination. “They’re just these cute little bugs,” says Frank Meek, technical services manager at Rollins.

Here’s what you need to know about what ladybugs eat to thrive, plus why these teeny critters can actually be great to have in your garden.

What are ladybugs, exactly?

Ladybugs are actually “lady beetles” that belong to the family Coccinellidae, says Howard Russell, M.S., an entomologist at Michigan State University. Despite the name, though, not all ladybugs are female.

“Europeans have called these dome-backed beetles by the name ‘ladybirds,’ or ‘ladybird beetles,’ for over 500 years,” says Nancy Troyano, Ph.D., a board-certified entomologist and director of operations education and training for Rentokil North America. “In America, the name ‘ladybird’ was replaced by ‘ladybug.’” (There are also more than 500 different species of insects we call ladybugs!)

In case you’re not familiar with them, ladybugs are small—usually less than ¼ inch long, Russell says—with a round or oval shape and a bright orange or red color. “Their blood or hemolymph contains toxins that repel or discourage would-be predators,” Russell says, meaning their bright coloring probably servings as a big warning sign.

Ladybugs also don’t survive long—they typically die off after four to seven weeks.

What do ladybugs eat?

Ladybugs like to feast on teeny sap-sucking insects known as aphids. “Over its lifetime, a ladybug may consume as many as 5,000 aphids,” Troyano says. “As larvae, ladybugs eat pests by the hundreds. A hungry ladybug adult can devour 50 aphids per day.”

While most ladybugs take on “soft-bodied insects and mites” a few species, like Epilachna varivestis, will feed on plants, Russell says. Overall, though, “almost all ladybugs feed on soft-bodied insects,” Troyano says.

Are ladybugs helpful in keeping pests away?

Most are. In fact, several species of ladybugs were brought to the U.S. in the mid-1900s “specifically to fight agricultural pests,” Meek says. Troyano calls ladybugs “beneficial predators of plant pests,” noting that “gardeners welcome ladybugs with open arms, knowing they will munch on the most prolific plant pests.”

Ladybugs may also keep other insects and animals away that could munch on your plants. “A ladybug’s bright colors warn predators to stay away,” Troyano says. “Insect-eating birds and other animals learn to avoid meals that come in red and black, and are more likely to steer clear of a ladybug lunch.”

Can ladybugs become a problem?

Plant-feeding ladybugs could potentially harm your plants when there are a lot of them, Russell says. (But, again, most ladybugs aren’t interested in noshing on your garden.)

But the biggest concern with ladybugs is when the temperature drops. “Ladybugs can become a problem during the colder months,” Troyano says. “They are what we in pest control commonly refer to as overwintering invaders.”

In the fall, ladybugs will “flock to buildings and look for an opening to enter to safely wait out the cold winter months,” she says, which is why you may notice them in your house when you turn the heat on.

One thing to consider, per Troyano, if you happen to spot ladybugs in your home: They defend themselves by emitting a “foul-smelling” secretion that’s actually their blood. “The blood can permanently stain walls, drapes, carpeting, and other surfaces,” she says. “And although these insects are not aggressive towards humans, ladybugs can bite humans when handled.”

It can also be concerning if ladybugs die inside your home. “Other pests, such as carpet beetles and ants, may come in and feed on the dead ladybugs,” Meek says. “Then those pests would move into the house and start looking for other food sources.”

So, do your best to make sure they don’t have an easy way to venture inside your home by tightly sealing any entry points before autumn hits.