Beneficial Insects

As gardeners, we are well acquainted with pest control. Japanese beetles, aphids and caterpillars are the bane of our existence, and a sizable portion of our time in the garden is spent trying to get rid of them. There are chemical controls, and also products like neem oil — which are made from natural ingredients — but there’s also another method of pest control, and that is to fight insects with insects.

Why beneficial insects?

Because they greatly reduce, if not eliminate, the need for chemical pesticides (which also kill the good insects). Perhaps more concerning than harsh chemicals in and on your food is the fact that a number of insect species are starting to show resistance to conventional pesticides, according to the EPA and many watchdog organizations. Garden pests do not, however, become resistant to natural predator — which is why they’ll be effective forever.

If you’re an organic gardener, keeping pesticides out of your garden is going to be high on your list. The presence of beneficial insects is an integral part of accomplishing that: it goes hand in hand with soil health, water conservation and chemical-free disease control as a central pillar of sustainable gardening practices.

Before you invite them in …

If you’d like to move forward with the adoption of some “good bugs” for your garden, there are a few checks that need to be performed:

  • Check to see if you need a special permit. Your local cooperative extension service will be acquainted with this information.
  • Check your neighbor’s pesticide-use habits. It would be a terrible waste to spend a fair amount of money on beneficials and then have your neighbor spray them all. Let nearby homeowners know about your plan. Once you tell them what you’re doing, they may want to join in and help you defray the cost.
  • Check to make sure you have enough “bad bugs” for the beneficials to eat, or they may migrate away from your garden in search of more satiating hunting grounds.

To keep beneficial insects from leaving the area after your “bad bug” problem is under control, make sure you’ve planted plenty of native trees, plants and grasses.

Consider yourself warned: these are not inexpensive, so you have to look at the cost as an investment in your garden and the local ecosystem. If you’re lucky, one or more of them may be native to your growing zone.

Here are 14 beneficial insects that will dutifully serve as sentinels for your garden, along with a list of which pests they prey upon, and a short list of plants that attract each beneficial. A final note: The bad bugs won’t be gone overnight; sometimes it takes a week or two to break the hatching cycle. With a little patience and a variety of habitats to attract beneficial insects to your garden, it won’t be long before those pesky pests will stop bugging you!

Beneficial Insects:


Aphid Midge

Name
Aphid Midge

Prey
Aphids

Attractor
Dill
Nectar-filled plants
Pollen-heavy plants


Braconid Wasp

Name
Braconid Wasp

Prey
Caterpillars
Hornworms

Attractor
Common Yarrow
Fern-Leaf Yarrow
Lemon Balm
Parsley


Damsel bug

Name
Damsel Bug

Prey
Aphids
Cabbage Worms
Caterpillars
Mites

Attractor
Caraway
Fennel
Goldenrod
Spearmint


Green Lacewing

Name
Green Lacewing

Prey
Aphids
Leafhoppers
Mealybugs
Whiteflies

Attractor
Angelica
Coriander
Dill
Golden Marguerite


Ground beetle

Name
Ground Beetle

Prey
Caterpillars
Colorado Potato Beetles
Cutworms
Slugs

Attractor
Amaranthus
Clover
Evening Primrose


Hoverfly

Name
Hoverfly

Prey
Aphids
Caterpillars
Scale
(Adults feed on pollen)

Attractor
Dill
Basket of Gold Alyssum
Common Yarrow
Fern-Leaf Yarrow
Statice


Ladybug

Name
Ladybug

Prey
Aphids
Colorado Potato Beetles
Fleas
Mites
Whiteflies

Attractor
Dill
Dandelion
Basket of Gold Alyssum
Common Yarrow
Fern-Leaf Yarrow


Mealybug Destroyer

Name
Mealybug Destroyer

Prey
Most Mealybugs

Attractor
Angelica
Dill
Fennel
Goldenrod
Sunflower


Minute Pirate Bug

Name
Minute Pirate Bug

Prey
Aphids
Caterpillars
Spider Mites
Thrips

Attractor
Alfalfa
Caraway
Fennel
Goldenrod
Spearmint


Praying Mantis

Name
Praying Mantis

Prey
Beetles
Caterpillars
Crickets
Moths

Attractor
Cosmos
Dill
Marigolds
Tall grasses


Soldier Beetle

Name
Soldier Beetle

Prey
Aphids
Grasshopper eggs
Soft-bodied insects

Attractor
Goldenrod
Linden
Marigold
Zinnia


Spider

Name
Spider

Prey
Aphids
Bed bugs
Fruit flies
Grasshoppers
Roaches

Attractor
Tall plants (weaving)
Mulch (predatory)


Tachinid Fly

Name
Tachinid Fly

Prey
Gypsy moths
Japanese beetles
Cutworms
Squash bugs

Attractor
Buckwheat
Carrot
Cilantro
Dill


Trichogramma Wasp

Name
Trichogramma Wasp

Prey
Moths
Scale
Flies
Aphids

Attractor
Carrot
Cabbage