This Lady's No Bug

Happy is the gardner with a lot of ladybugs around. These colorful beetles consume huge quantities of garden pests.

Ladybugs capture our imagination like few other insects. They are the subject of nursery rhymes and symbols of good luck, and they are just as fascinating to grown-up gardeners as they are to children.

Despite their name, however, ladybugs are not always ladies, nor are they bugs. Like all species that reproduce sexually, some of the “ladies” are male. And ladybugs are actually a kind of beetle. Beetles, although similar to bugs, are an altogether different order of insect. Bugs have sucking mouthparts and feed on fluids. Beetles have biting mouthparts for tearing their food, which allows many beetle species to prey on other invertebrates. Technically, the proper common name for these brightly colored insects is “ladybird beetle,” but it’s okay to call them ladybugs.

Ladybugs are most famous for their taste for aphids, but they will dine on any number of soft-bodied garden pests, including scales, whiteflies, mealybugs, thrips, mites, caterpillars, and beetle larvae. One ladybug can consume 5,000 pests in its lifetime. Here’s how to make your garden a haven for these beneficial insects:

Identify different types of ladybugs. There are around 5,000 ladybug species, and not all are red with black spots. Some have yellow, black, or orange backgrounds, and some have white spots. Different species have different numbers of spots, and some have no spots at all. One of the most common species is the convergent lady beetle (Hippodamia convergens), which is found across North America. Increasingly common is the multicolored Asian ladybug (Harmonia axyridis), an introduced species that has spread rampantly and is now considered an invasive exotic pest (see sidebar). After color, the best way to identify which ladybug species you have in your garden is to count the number of spots and then refer to a field guide.

In the photo shown above, the convergent lady beetle is one of the most common in North America. It eats garden pests such as aphids and mites.

Learn to love their larvae. Like all beetles, ladybugs start out as soft-bodied larvae that eventually pupate and emerge as hard-shelled, winged adults. (Bugs, unlike beetles, hatch from eggs as miniature versions of the adults.) Newly hatched ladybug larvae are often described as looking like tiny alligator heads because of their shape and scaly-looking bodies. They have various color patterns, depending on the species. Learn what the larvae look like so you don’t accidentally kill them when you find them on your plants. Like adult ladybugs, the larvae are voracious predators and an important form of natural pest control.

Put poison-free pests and wildflower pollen on the menu. Avoid pesticides if you want to attract ladybugs to your garden. Yes, this means you might see more pests in your garden, but it also means natural predators will be there as well, keeping pests in check so they don’t cause significant damage. Ladybugs also feed on pollen and nectar, so plant a variety of native wildflowers or even let part of your yard grow wild. If you have a healthy habitat, you won’t have to purchase ladybugs; they’ll show up on their own. Whether in larval or adult forms, the presence of ladybugs in your garden is a sign that things are in a natural balance. Maybe there is something to the idea that they’re a sign of good luck!


Not-so-Nice Ladybugs
The multicolored Asian ladybug (Harmonia axyridis) was deliberately introduced into the United States by the USDA as a form of pest control, only to eventually spread and become something of a pest itself. In some areas it has displaced rarer native ladybug species.

Unlike natives, this ladybug swarms and invades homes for winter hibernation; exudes a smelly, staining liquid when disturbed; and is known to bite people. This species is also known as the Halloween ladybug because of its red-orange coloration, which makes it look like a tiny pumpkin. It has a varying number of spots, making identification difficult. To be certain, look for an M-shaped spot pattern just behind the head.

To prevent these ladybugs from entering in the fall, tightly seal windows and other potential entry points. If they’re inside your home already, the quickest and least toxic way to get rid of them is to simply vacuum them up.