Not many people know exactly that a species of ladybugs are actually predators. Adult and even larval ladybugs consume other insects which have soft bodies, such as mites, white flies, caterpillars, insect larvae and scale insects.

 

The common theme among these types of insects in the ladybug’s diet is that they are pesky plant-eaters, and one most common are aphids, which are very well-known pests to those who garden. This is one of the reasons that ladybugs are often nicknamed as a “gardener’s best friend,” due to their consumption and control of plant pests. 

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According to Biological Control, Lady beetles are voracious feeders and may be numerous where prey is plentiful and broad-spectrum insecticide use is limited. Ladybugs need to consume large amounts of aphids per day in order to lay eggs. Convergent ladybugs may eat their weight in aphids every day as a larva and consume as many as 50 aphids per day as an adult, whereas sevenspotted lady beetle adults can consume hundreds of aphids per day and each larva eats 200 to 300 aphids as it grows. After the adults and larvae have taken out an aphid colony, they will then search for more food.

 

Lady beetles are effective predators if aphids are abundant but are thought to be less effective at low pest densities. There could also be crop damage before lady beetles make an impact on an aphid population.

 

Most of the lady beetle species are active from the late spring to early fall if there is food available. For the members of the ladybug family that consume plants, the squash beetle (Epilachna borealis) and the Mexican bean beetle (Epilachna varivestis), their diets consist of herbs and plants such as flower nectar, water, honeydew, coriander, yarrow, caraway, fennel,

and dill.