Lady Beetles, Part 2

Lee Royer
Frederick County Master Gardener

Read Part 1

Lady beetles, ladybugs or ladybirds as the British call them, are probably the most easily recognized of all beneficial insects. Scientifically they belong to the Family Coccinellidae and the Genus Hippodamia. Their hard bright red or orange shells are actually covers protecting transparent wings which can beat 85 times a second while flying. Most have dark spots on their shells. Spots often don't appear for 24 hours after they emerge from the pupa stage and fade as the bug ages. Some varieties can live 2 or 3 years if conditions are good. Cute and colorful is nice but what gardeners and farmers really love about ladybugs is their huge appetite for soft bodied pests such as aphids, spider mites, mealy bugs, and eggs of others such as the Colorado Potato Beetle and European Corn Borers which destroy our crops and ornamental vegetation.

The native American ladybug variety most widely available for purchase is the Convergent Lady Beetle (Hippodamia convergens) named for converging white marks just behind the head. Studies show normal adult Convergents eat almost 60 aphids a day, 500 or so, before laying a lot of eggs, sometimes over 1,000, which hatch into hungry larvae resembling tiny alligators. Larvae eat 25 or so aphids per day for a few weeks, until a short pupa stage after which they become adults and start the cycle all over, often several times a summer. Shorter days and cooler weather trigger the urge for hibernation when Convergents congregate in large numbers over the winter. This is when Convergents are collected by dealers, usually from the mountains of California where they can be found in large colonies. These collections are put in cold storage where they remain until purchased by retailers or sold directly to you.

Buying lady beetles is a gamble. Set free in early spring, the beetle's huge appetites and high reproductive rate very quickly deplete the local food source and they fly away to find more food before winter sets in. Those released in hotter summer months may have reduced feeding and reproduction rates. In some cases for unknown reasons most of the lady beetles will leave regardless of the availability of food.

There are a few things you can do to increase your chances of success with shipped in beetles. Buy native species if you are given a choice. Buy as close to the source as possible from a company that specializes in selling live insects such as Gardens Alive or Growquest. Read all the fine print before ordering. Purchase ladybugs guaranteed to be parasite free and pre-fed. Follow directions closely for what to do once you have received them. Reputable companies will know what works for their particular beetles. Most will tell you to hydrate the beetles with a spray of water, juice or soda and then release them in the evening or at night on a wetted area.

Another approach to increasing your ladybug population is to encourage locals by growing plants that attract them such as fennel, dill, cilantro, yarrow, and scented geraniums. Needless to say, don't use pesticides if at all possible. Resist killing any other bugs or eggs in the garden unless you have positively identified them as bad. If you have a question about which are good and which bad, call the number at the bottom of this article for help or take a few specimens to one of our plant clinics held each week during the summer months at the Farmers Market on Baughman's Lane.