Caren White is a Master Gardener and instructor at Home Gardeners School. She has been associated with Rutgers Gardens for over a decade.
Growing your own food organically is best for your health and the environment, but how do you control destructive insects if you can’t use chemicals? The answer is to invite their enemies into your garden. "Enemy" insects are known as beneficial insects because they benefit the plants in your garden rather than destroying them. There are two types of beneficial insects:
- Insects that pollinate your plants
- Insects that eat the insects that destroy your plants.
What are Ladybugs?
Ladybugs (Coccinellidae spp) are not actually bugs. They are small beetles. There are 200 different native species of ladybugs in North America. More recent arrivals are Asian ladybugs which hitched rides on international trade goods and are now happily living in our yards and eating destructive insects. Whether native or foreign,all ladybugs are red or yellow with differing numbers of black spots. But it’s not just the adults that do the most good. The ladybug larvae are voracious consumers of aphids.
Ladybugs lay their orange or yellow eggs in clusters near aphid colonies. The eggs hatch in about a week. The larvae resemble tiny black alligators with yellow or orange markings. They feed on the aphids until they pupate into adults in about a month. Young larvae eat several dozen aphids per day. Older larvae can consume up to 100 aphids per day.
To have larvae, you need adult ladybugs. To encourage the adults to come to your yard and lay their eggs, provide an attractive environment for them including favorite foods, water and someplace to hide.
What Do Ladybugs Eat?
Ladybugs love to eat pollen as well as insects. They have some favorite pollens, so plant the following flowers and herbs in your garden to attract hungry ladybugs to your yard.
- Scented Geraniums
- Sweet Alyssum
Keep the flowers deadheaded so that the plants will keep producing flowers all summer long. Once the flowers die, the plants will produce seeds instead of new flowers so cut off any flowers that have begun to die.
Be sure to leave part of your yard a little “weedy”. Ladybugs also love the pollen of dandelions and Queen Anne’s Lace.
How to Provide Water for Ladybugs
It’s tempting to leave a bowl of water outdoors for the ladybugs, but that could attract mosquitoes if not emptied and refilled every day. Plus ladybugs could drown in it if the bowl is too deep. It’s better to use a shallow bowl of water which is filled with marbles or small stones to give them something to perch on as they sip the water.
Don't Buy a Ladybug House
Don’t waste your money buying or building a ladybug house. Ladybugs don’t nest like some insects but they do need protection from predators such as toads or birds during the day. Provide them with low growing plants such as thyme or oregano or even straw mulch to hide in.
In the winter, ladybugs hibernate. The Asian ladybugs like to hibernate in our warm houses while the native ones hibernate in leaf litter, a good reason not to rake up your leaves in the fall.
Can You Buy Ladybugs?
Introducing mail order ladybugs to your yard can actually reduce the local population of ladybugs. Ladybugs that are purchased via mail order are wild caught. Since they are most likely coming from a different part of the country, they may be carrying diseases or parasites that don’t exist in your part of the country. The ladybugs in your area will not have any resistance to these “foreign” diseases. They may die or their lives may be shortened so they will lay fewer eggs, resulting in fewer adult insects.
Another problem with wild-caught ladybugs is that they are very often harvested while they are hibernating, so they aren't ready to feed when you release them. They will just fly off no matter how tempting your local aphid population or pollen plants may be.
© 2017 Caren White
Caren White (author) on June 04, 2017:
Susan, that's fascinating! Thanks for sharing your experience from across the pond. Ladybugs are also called Ladybird beetles here in the US.
Susan Hambidge from Kent, England on June 04, 2017:
I am lucky to have quite a number of ladybirds (UK name) on my foxglove plants. They seem to like these flowers, as do the bees. I didn't know they also like marigolds, I will seriously look at adding some of them. Thanks you.