Of all the insects we find in the garden, lady beetles have to be one of our favorites. Lady beetles don’t harm any of our plants, but they spend their lives eating those who do. Because of that, we all need some lady beetles in our landscape.

Now some of you are thinking “why is he saying lady beetle?” Well, I’m calling them lady beetles because that is the correct name, even though ladybugs is a much more popular name for these garden-friendly insect. If you really want to throw people off, you can call them ladybirds, but I’ve never heard anyone call them that.

While we have about 450 different varieties in North America, the one most of us have seen and are familiar with is the convergent lady beetle, aka Hippodamia convergens Guérin-Méneville. That’s quite a mouthful.

This insect with many names is great for your garden because both the larvae and the adults are voracious predators of other insects. I know they look cute, but an adult lady beetle can eat up to 50 aphids a day. Since the aphid reproduction cycle is so quick, lady beetles are great to have around to help keep your aphid population down to a minimum.

Lady beetles reproduce via a process called “complete metamorphosis” which is different from “incomplete metamorphosis.” For an example of incomplete metamorphosis, let’s look at grasshoppers. When baby grasshoppers hatch from their eggs, they look like a tiny grasshopper. As they grow, they go through several growth stages called “instars.” During each growth stage, grasshoppers are limited by their external shell. When they get too big for their shell, they shed the shell and emerge a larger grasshopper. This process continues until they reach adulthood.

When lady beetles hatch from their eggs, they are a larva. These larvae molt several times as they grow as they move to the pupae stage, emerging from this stage as an adult lady beetle. This is called complete metamorphosis.

Lady beetle eggs are orange and are typically deposited on leaves in clusters near a food source such as aphids. They hatch in about 5 to 7 days as larvae and begin to eat. These lady beetle larvae look a little more like a predator insect that the adult lady beetle, but both can hold their own in the dining department.

After hatching, these lady beetle larvae go through three instars over a period of about 2 weeks. When this stage is over, they attach themselves to a surface for what is known as the prepupa stage for a couple of days. Once the pupal stage begins, the adult lady beetle will emerge in about 5 to 8 days. This life cycle can repeat itself 2 to 3 times a year.

Toward the end of our growing season when the temperatures start to cool down, lady beetles search out a nice, protected place in which they can overwinter. These homes can be behind bark flaps on trees or under plant debris in the garden. The fact that a variety of insects over-winter in plant debris is one of the reasons we suggest gardeners delay clean-up of the garden until early spring when it begins to warm up. While in this over-wintering period, lady beetles enter into what we call diapause, which is kind of like hibernating.

During the growing season if you find yourself with an aphid problem, you can visit your favorite garden center to purchase containers of lady beetles. They will take care of the problem, but once the food runs out, they will move on in search of other sources of food.

Rather than purchasing lady beetles, a better solution is to make your garden a place lady beetles would like to visit. Since they also like to feed on nectar and pollen, having plants on hand to provide a consistent source of both of these will make your garden a welcome destination. Good flowers for lady beetles would include alyssum, coriander, and dill.

If you are hoping to let nature take its course with lady beetles devouring your aphids, you will need to be very careful with the pesticides you use in your garden. If you are planning on trying to rid your garden of aphids yourself, start with a strong stream of water. Aphids are very small, fragile insects that can’t hold up well to a stream of water and this water won’t kill any potential lady beetles.

While pesticides are an effective way to deal with pests, we’re much better off creating a garden that is attractive to a variety of insects and even birds. There is also a certain amount of patience involved, patience meaning that we don’t reach for the pesticide when we first see an insect threat to our plants. In the case of aphids, if we use a stream of water initially, the lady beetles will find your aphids and make quick work of them. Just give the natural process a chance to work first. See you in the garden.

You can get answers to all your gardening questions by calling the Tulsa Master Gardeners Help Line at 918-746-3701, dropping by our Diagnostic Center at 4116 E. 15th Street, or by emailing us at mg@tulsamastergardeners.org. Photo: Susan Ellis, Bugwood.org