The eggs of some lady beetles are yellow and less than 1/l6 inch long. They are often laid on end in small masses. The eggs of others are scale-like and flat on the twigs of the plants. From the eggs hatch larvae, small insects that resemble tiny, short-snouted "alligators" with six legs. Some lady beetles have larvae covered with a fluffy white secretion which makes the insect look like a mealybug. The next stage is the pupa. Pupae are about the size of the adults, but the legs and antennae are closely pressed to the body. Also, the wing buds wrap around the body. The pupae are usually anchored to the substrate at the rear.
Because lady beetle pupae do not resemble the adults (or anything else in the home gardener's experience) the many gardeners assume that lady beetle pupae are pests "sucking the life" out of the plant. Consequently, these pupae are squashed or scraped off and destroyed. Each lady beetle larva eats many aphids and other pests, and each lady beetle lays many eggs which would hatch into many more larvae. Each pupa destroyed allows thousands of aphids to survive.
A recently introduced species called the multicolored Asian lady beetle (Harmonia axyridis) sometimes congregates in large numbers inside of houses in the fall and is considered a pest in that situation. It eats a lot of soft bodied insects, but may be displacing some of our native lady beetle species. For information on this lady beetle consult Ornamentals & Turf Note #107.
Also called ladybirds and ladybug, lady beetles are regarded with more popular affection than any other beetles. Eggs are laid near aphids, scale insects, or spider mites. After hatching, the tiny lady beetle larvae feed on nearby plant pests. The larvae molt several times as they grow. Finally, the last stage larvae fastens itself by the rear end to a leaf or twig and then pupates. The pupae develop for several days. New lady beetles then emerge from the pupal stages.
In the fall, adult lady beetles seek a dry, sheltered overwintering site. The following spring the lady beetles disperse to find plant pests for food and oviposition (egg laying) sites. In North Carolina, lady beetles overwinter in small groups (rarely up to 300 to 400 individuals). In western states, lady beetles congregate by the millions along mountain ridges. Thus it is possible for collectors to scoop bushels of lady beetles to sell to home gardeners for aphid control. To reach their hibernation site, western lady beetles have to fly for long distances. Consequently, when they leave the overwintering site in spring, they instinctively fly for long distances to reach a source of aphids or other host insects.
Although lady beetles are helpful and cute, they are not clever. Thus when lady beetles from California are released into a North Carolina landscape, the beetles instinctively fly for long distances in search of aphids and other plant pests as though they were still in California. The home gardener who releases a quart of lady beetles may never see them again. At least some satisfaction will be gained by helping to control aphids in someone else's garden.
For the average home gardener, we generally don't suggest purchasing lady beetles for insect control. Some shipments of ladybeetles have also been found to be already parasitized and may have a short life and no reproductive capacity, especially when they come from field-collected populations. However, if the reader wishes to purchase lady beetles to be released in the home grounds, the following conditions may help keep the lady beetles in the vicinity.
On the other hand, ordering, the lady beetles in expectation that aphids will arise in the home grounds may mean that the lady beetles arrive before the aphids do and there will be nothing for them to feed on so they will certainly leave.
2) Always release the lady beetles in the evening when the weather is cooler.
3) Sprinkle the area with water where the beetles are released.
For assistance, contact your county North Carolina Cooperative Extension Service agent.
Published by North Carolina Cooperative Extension ServiceDistributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Employment and program opportunities are offered to all people regardless of race, color, national origin, sex, age, or disability. North Carolina State University at Raleigh, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.
ENT/ort-74 April 1994 (Revised) May 1997
Web page last reviewed January, 2011 by the webperson.