Lowe's Home Improvement

Recognize Beneficial Insects

Insects are plentiful in summertime, but not all are harmful. Before you grab the bug spray, take a closer look. Beneficial insects can be a gardener's best friends, pollinating your flowers and helping to control unwanted pests.


What are Beneficial Insects?

Beneficial insects help manage pest populations in the garden. Greenhouse and orchard operators have used them to control pests for years. The key word is control - complete prevention of insect pests is not a realistic expectation. Pesticides are efficient; however, spraying eliminates not only the pests, but also the beneficial insects. In addition, pesticides also require regular applications, but a population of good bugs provides ongoing pest control service.

Beneficial insects operate by one of three methods:

  1. Predators control insect pests by feeding on them. Some predators eat hundreds of pests in a single day.
  2. Parasitic insects lay their eggs in, on, or near their chosen victim. Their larvae feed on and eventually kill their host. Smaller numbers of pests are destroyed by parasites than predators, but the outcome is the same.
  3. Pollinators, especially bees, ensure the flowering and fruiting of the garden. Without this group’s contribution, there would be no gardens.

How to Attract Beneficial Insects

You have more good bugs than you imagine in your garden already; otherwise, your garden probably wouldn’t be there. If you want more good bugs, attract them with plants. Pollen and nectar-producing plants, especially perennials, offer shelter and food. Some examples include catnip, dill, parsley, yarrow, daisies, alyssum, cilantro, Queen Anne’s lace, thyme, clover and goldenrod.

Water is also a welcome addition during hot dry times. A saucer of water with a stone placed in it for insects to rest on is a simple water source. Keep the water fresh to prevent mosquitoes.

Your six-legged mercenaries can also be purchased from specialty insect farms. They’re often shipped as eggs or larvae, so don’t expect them to pounce on the bad guys immediately. Introducing beneficial insects to your garden is a long-range remedy, not an immediate solution. It may take a few weeks for the newcomers to get busy. Even then, they may eat the pests, then die or fly away. Ideally, they will eat the pests, stick around and raise a family, beginning a resident population.

Follow the supplier’s instructions carefully to ensure the most efficient time and method for establishing your new residents.

Beneficial insects help in the battle against garden pests, but don’t expect complete eradication of the enemy. In spite of your efforts, occasional spraying may be necessary.

Common Beneficial Insects

All of the insects listed below are predators except for the Tachinid Fly and Trichogramma Wasp – they are parasitic.

Assassin Bug

Assassin bug.

They earn their pretty cool name by sneaking up on and attacking their prey. Assassins are up to 1 inch long and are identified by their long head and curved beak. They can also inflict a painful bite on humans. Assassin bugs prey on mosquitoes, flies, caterpillars, beetles and anything else that moves.

Ground Beetle

Ground beetle.

Ground beetles are up to 1 inch long, with black or brown shells. They like to hide under yard debris and loose bark. There are many varieties and shapes. They are welcome consumers of cutworms, maggots, snails and slugs.



Adult lacewings are about 3/8 inch long. Their delicate wings easily identify them. They eat aphids, thrips, lice and other larvae.

Ladybug or Ladybeetle


The larvae resemble alligators and are just as ravenous as the more easily recognized and familiar adult beetles. They eat aphids, thrips, tree lice and other larvae.

Praying Mantis

Praying mantis.

Fascinating to observe, the praying mantis can grow up to four inches long. There is some debate about keeping praying mantis since they will eat anything, including their own kind.

Soldier Beetle

Soldier beetle.

About 1/2 inch long, they resemble lightning bugs. Soldier beetles primarily eat caterpillars, bean and potato beetles.

Tachinid Fly

Tachinid fly.

Similar to a house fly, only hairier, tachinids tend to stay near plants, not people. They attack moths, bean and potato beetles, grasshoppers, caterpillars and cutworms.

Trichogramma Wasp

Trichogramma wasp.

Don't let the word wasp scare you — this species is too small to see but is a valuable control. This wasp preys on worm larvae, borers, webworms, leafworms and cutworms.