Take advantage of biological controls in your garden by encouraging natural predators, such as praying mantids, ladybugs, lacewings, and ground beetles. Increase their populations by providing shelter, food, moisture, and overwintering sites. Some beneficial insect suppliers offer a formulation for feeding/attracting the beneficials to keep them in the garden longer.

Learn to recognize the eggs and larvae of the beneficial insects, and avoid harming them. You can often find praying mantis egg cases in weedy lots. Carry the twig with the cluster attached into the garden and set it in a place where it will not be disturbed. Learn to recognize parasites and their egg cases. For example, the tomato hornworm is often seen with a number of white cocoons, a little larger than a grain of rice on its back. These are from a parasitic wasp. The hornworm will die and more wasps will emerge. Obviously, it is to your advantage to leave that caterpillar in the garden.

Another possibility is to increase the type and number of plants in your landscape that will attract beneficial insects. Most composite and umbel plants attract beneficial insects by providing nectar and pollen that prolongs the insects life. Cosmos and marigolds will attract a few beneficial insects, while tansy will attract large numbers. Best results come from planting the attractant plants on the edges of the area instead of interplanted in the garden.

Beneficial insects are often killed when insecticides are applied. A selective insecticide has less adverse effect than a broad spectrum insecticide. Stomach poison insecticides, are less likely to harm beneficial insects.

Consumer Horticulture | Quick Reference

© Erv Evans, Consumer Horticulturist
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