Do Ladybugs Protect Plants?

Identifying Ladybugs

• The most common ladybug has a rounded red body with black spots on the wings. The beetles also can be yellow, pink, orange or black, with or without spots. The female lays clusters of tiny gold eggs on the underside of a leaf or on a plant stem. The larvae, which hatch in about a week, are dark gray with orange spots or stripes and resemble tiny alligators.

Benefits

• When the larvae hatch, they begin feeding on aphids, spider mites, mealybugs, thrips and the eggs of other insects, particularly the eggs of the potato beetle. Larvae eat about 400 aphids before pupating; adults eat thousands more.

Attractors

• In addition to insects, ladybugs need nectar and pollen, so planting flowers will help attract and keep them. Tiny, fragrant flowers work the best, so let some of your herbs and vegetables go to seed. Other flowering plants that attract beneficial insects include alyssum, baby's breath, monarda, calendula, coreopsis, cosmos, marigold, sunflowers, yarrow and zinnias. Don't use pesticides on your plants, because most pesticides kill the ladybugs as well as the pests.

Buying

• Ladybugs overwinter in California, where they are gathered for sale to gardeners and growers. A package usually contains about 1,000 ladybugs. Release them just before sunset, after wetting the infected plants so they will have water to drink upon release. If there aren't enough pests to sustain them, they will fly to other areas. Ants, which feed on the sweet secretions of pests such as aphids, will defend the plant against ladybugs, so try to blast the ants off with a hose or spray bottle before releasing the ladybugs.