Using beneficial insects in the garden is a great alternative to chemical insecticides. They will help control the pest population in a natural way.
LADYBUGS: Ladybugs eat a wide variety of insect pests including aphids, mealybugs, spider mites and whiteflies. Plants that will help attract ladybugs include marigolds, butterfly weed, yarrow, roses, goldenrod, cucumbers, peppers and tomatoes. You can also purchase ladybugs and release them in your garden. Be sure to have several plants available to keep them around and help the ladybugs feel at home.
PRAYING MANTIS: Most praying mantis are green or brown, They range in size from 2 to 12 inches in length. They are carnivorous insects that are very beneficial to gardeners. Pests they eat include leaf hoppers, aphids, and small flies to name a few.
GREEN LACEWINGS: These insects feed on aphids, small caterpillars, white flies, mites and mealybugs.
TRICHOGRAMMA WASPS: Most people have never heard of the trichogramma wasp. These minute insects are so small several can fit on the head of a pin. They are very tiny parasites that have a big impact on garden pests. The trichogramma wasp larvae kills pests by consuming their eggs. Effective on cabbage worm, tomato horn worm, corn borer and cane borers. These wasps can also be purchased from many online sources. Follow the recommendations carefully.
There is a chance that upon releasing beneficial insects into your garden they will fly away. But if you have a wide variety of pests for beneficial insects to feed on, they may remain in and around your garden to considerably reduce harmful pests. Happy Gardening!