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:
- Predators control insect pests by feeding on them. Some predators eat hundreds of pests in a single day.
- Parasitic insects lay their eggs in, on or near their chosen victim. Their larvae feed on and eventually kill their host. Parasites destroy fewer pests than predators do, but the outcome is the same.
- 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 in your garden than you imagine. 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.
So long as you have a body of water around the house, gardening for insects is not that hard — especially 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.
Should I Buy Insects for My Garden?
If you don't have enough beneficial insects around your home, you can buy them online from a specialty pest control website. When purchased, the insects will be delivered to you in eggs. Most beneficial insects should be able to adapt to your area's climate, so the insects should be able to survive and thrive without issues.
Your six-legged pest predators 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. Some may die or fly away, but ideally, the remaining insects will eat the pests, stick around and reproduce. Follow the supplier’s instructions carefully to successfully establish your new residents.
While beneficial insects help in the battle against garden pests, don’t expect complete eradication of the enemy. Occasional spraying may still be necessary.
Alternatively, animals such as birds, ducks and chickens can also hunt for insects. Just be sure to keep animals away from your crops and flowers with fencing, raised garden beds and other methods.
Is it Good to Have Ladybugs in My Garden?
While ladybugs may appear cute and harmless, they're actually useful predator bugs. They feed on aphids, which could eat your plants and cause them to become diseased if left unchecked. The average ladybug eats roughly around 50 to 60 aphids per day — and up to 5,000 aphids in its lifespan. So if you see a ladybug, don't harm or remove it — allow it to keep doing its natural job.
Common Beneficial Insects
All of the insects listed below are predators except for the Tachinid Fly and Trichogramma Wasp — they are parasitic.
Assassin Bug
These bugs earn their 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 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.
Lacewing
Adult lacewings are about 3/8-inch long. Their delicate wings let you easily identify them. They eat aphids, thrips, lice and other larvae.
Ladybug or Ladybeetle
The larvae resemble tiny alligators and are just as ravenous as the more easily recognized and familiar adult beetles. As mentioned above, they eat aphids as well as thrips, tree lice and other larvae.
Praying Mantis
A praying mantis can be fascinating to observe and can grow up to 4 inches long. There's some debate about keeping praying mantis since they'll eat anything, including their own kind.
Soldier Beetle
These beetles are about 1/2 inch long and resemble lightning bugs. Soldier beetles primarily eat caterpillars, bean beetles and potato beetles.
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
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.