11 Household Insects Who Provide Biological Pest Control

A spined soldier beetle climbs on a leaf.

With all the over-the-counter pest products and professional pest control services available, it's easy to forget that plenty of household pests offer major benefits to our homes and gardens. But it's true!

Take a look at some of nature's greatest landscape assistants below. And next time you find yourself reaching for expensive and potentially harmful chemical products, try harnessing the powers of the wild instead with these clever, collaborative critters.

1. Praying Mantises

The distinctive looking mantis cuts an imposing figure, and well it should. This little dragon is a hunter of yard pests. Don't let the stick figure fool you, the fearsome mantis eats most anything available, from beetles chewing on your greenery outside, to mosquitoes and even small lizards attempting to infiltrate your home.

2. Earthworms

If you have a flower or vegetable garden, you want earthworms in residence. Serve them up any regular patch of dirt and they'll devour the dead organic material within, along with any tasty bacteria and fungi, excreting fertilizer that improves the soil for plants. Give them a compost pile topped with mulch and they'll savor it like a decadent dessert. In the process, they'll move around constantly, keeping the soil aerated and making it even friendlier for root systems.

A pair of hands holds earthworms in dirt

3. Ground Beetles

For many ground beetles, an ideal buffet consists of slugs and snails. If you have an indoor garden, these insects will be your best friends. Calosoma beetles are especially useful to combat moth infestations. Unlike many other insectovores, they will happily snack on fuzzy caterpillars, which can consume your plants if left unchecked. A few species of ground beetles, such as the herbivorous Zabrus, may not make ideal gardening companions. So if you notice beetles on your plants, do some research to figure out what kind you're dealing with.

4. Tachinid Flies

The tachinid fly is an airborne pest controller. These brown, gray, or black flies are similar to houseflies, but they're happiest outside, where their preferred dinner items include cutworms, moth larvae, and caterpillars.

5. Lacewings

The delicate flapping of lacewings allows them to sneak up on garden pests such as aphids, caterpillars, red mites, and mealybugs. In the right conditions, a lacewing can eat as many as 100 aphids in a sitting.

6. Beneficial Nematodes

The beneficial nematode is a microscopic parasite that feeds on Japanese beetles, white grubs, and flea larvae. Your dog will thank you for allowing this pest to live in your yard. And your grass will stay rich and green, uneaten by potential pests beneath the earth.

A microscopic view of a nematode

7. Spined Soldier Bugs

The spined soldier bug lives up to its name, as it scouts for pests attacking your vegetable garden. It seeks out and eliminates cabbage worms, Colorado potato beetles, Mexican bean beetles, and hornworms, with the military focus of a knight on an everlasting quest.

8. Ladybugs

For outdoor vegetable gardens, the ladybug is an ideal companion. It can be the savior of the harvest by keeping plants free of potentially damaging aphids and mealybugs. If your ladybugs venture indoors, they'll provide the same care to your window or hydroponic gardens. These petite insects must have a fast metabolism—each can consume as many as 5,000 pests throughout their life.

9. Braconid Wasps

This mighty, fast-moving protector is especially useful for guarding succulent tomatoes and other exposed fruits from hungry horn worms who want to strip you of your salad.

10. Bees

When a bee buzzes by, you can be sure he or she is taking care of important business. While we don't want them flitting around in our home, many kinds of bees do a stellar job collecting and sharing pollen in our vegetable gardens and orchards, improving fruiting and flowering in some of our most valuable plants.

11. Spiders

Especially in areas teeming with mosquitos and flies, a healthy community of spiders can be an invaluable ally in the pursuit of a peaceful night outside. Birds love to eat these little web-slingers, too, so you can help the food chain in both directions by allowing spiders to take up residence in your outdoor spaces.

In nature, everything has a purpose. Use this to your advantage by cultivating pests that keep your yard healthy and defend your home. Before you pay for any more poison sprays, consider investing in some natural alternatives. In the long run, developing populations of beneficial insects will be better for both your wallet and the world.