At this time of the year, aphids can be a serious problem in the garden.  But salvation can arrive in the form of ladybugs. Ladybugs are actually beetles, not bugs.  And while they are sometimes called ladybirds or ladybeetles, of course they are not all female. They belong to the class Insecta and are members of the Coccinellidae family of beetles (Coccinellidae means “small red sphere” in Latin).

Ladybugs have oval-shaped bodies and appear in various colors, including red, yellow, gray, black, brown and even pink.  They may or may not have spots or stripes.  Ladybugs are beneficial insects that play a major role in keeping down populations of insects that feed on plants.  Perhaps most importantly, ladybugs are predators with an insatiable appetite for aphids. A ladybug can eat up to 5,000 aphids over its lifetime.  They can also help to rid your garden of other soft-bodied insects such as mites, mealybugs and leafhoppers, along with insect eggs and even ants. 

Of the 5,000 ladybug species found worldwide, 450 are native to North America, with 175 of those species found here in California. Adults mate in early spring (when temperatures reach above 65⁰F) and again in June if the aphid population is abundant. When aphid populations decline, ladybugs migrate to higher elevations.

Ladybugs undergo a complete metamorphosis during their life cycle, moving through four stages: Eggs à Larvae à Pupae à Adult.  The first 3 stages of life occur quickly, over one to two months. A single ladybug can lay up to 300 eggs.  After a female lays her eggs, they hatch in two to 10 days.  The eggs are yellow, oblong, and laid in clusters in an aphid colony so the larvae will have a food source as they emerge from their eggs. The larvae look like tiny alligators and are about one-quarter of an inch long and blackish with orange stripes.  Larvae eat and grow for another 21-30 days before entering the pupal stage, which lasts seven to 15 days.  Once it emerges from the pupal stage an adult ladybug will live for approximately one year. 

Adult ladybugs are four to seven millimeters long (around one-quarter of an inch). The ladybug anatomy consists of a head, two antenna, two eyes, a pronotum covering the thorax, an elytra (the hard shell that covers their wings), six jointed legs, abdomen and wings (these are so thin you can actually see through them). Interestingly, ladybugs beat their wings 85 times per second in order to fly.  When threatened a ladybug can draw its heads into its pronotum, like a turtle does, to protect itself.  

Ladybugs hibernate in the winter months and will not fly when temperatures fall below 55⁰F. They feed on pollen and nectar and live on stored fat through the winter. Ladybugs are not preyed upon by birds or other vertebrates because they exude a very distasteful fluid from joints in their legs; their distinctive colors are a reminder to would-be predators they taste “bad.”  When threatened, ladybugs will play dead. 

How can you attract ladybugs to your garden?  Wait for spring and check that you have a ready supply of aphids available. If there is no food, ladybugs will not come.  For successful handling and release of ladybugs purchased at retail stores, keep them refrigerated until time for release.  They may be dehydrated when purchased, so mist them with water from a squirt bottle before putting them in the refrigerator. Do not release them into your garden during the daytime or they will fly away immediately.  Instead, release them at dusk or early morning. Before releasing, spray a fine mist of water on plants that have aphids on them and place the ladybugs at the base of the plants.  Do not release ladybugs on plants that have been sprayed with insecticides as the chemical residues may kill them.  Be prepared for ladybugs to fly away in a few days as they typically don't lay eggs on the plants they have been released on.

When you see ladybugs, remember that they are considered lucky in many cultures, for various reasons.  Enjoy them in your garden until they fly away, fly away home.

The Master Gardeners Spring 2021 Workshop Series has begun.  Topics include:  Native Gardens, Invasive Plants, Honeybees, and a 4-part series on Firewise Landscaping. Visit our website to read about these upcoming free workshops and to register for them.

UC Master Gardeners of Butte County are part of the University of California Cooperative Extension (UCCE) system. To learn more about us and our upcoming events, and for help with gardening in our area, visit our website. If you have a gardening question or problem, email the Hotline at mgbutte@ucanr.edu (preferred) or call (530) 538-7201.