Ladybugs (family Coccinellidae) are recognized as beneficial insects and natural pest controllers in gardens worldwide. Their reputation often leads people to wonder if their diet includes common nuisances like mosquitoes. Ladybugs are effective predators, but they are not primary predators of mosquitoes. Their specialized diet focuses on pests that live on plants rather than those with aquatic or aerial life stages.
The Ladybug’s True Diet
The primary diet of most predatory ladybug species consists of soft-bodied insects and mites that infest plants. Their favorite food is the aphid, a tiny pest that sucks sap from plant tissues and can reproduce quickly enough to devastate crops. A single adult ladybug can consume hundreds of aphids per day, making them a valued ally for farmers and gardeners.
Beyond aphids, their menu includes scale insects, mealybugs, thrips, and spider mites. These prey items are relatively stationary, small, and lack a tough outer layer, making them easy targets for the ladybug’s chewing mandibles. Mosquitoes have a complex life cycle, spending time as aquatic larvae and highly mobile flying adults, which keeps them out of the ladybug’s usual hunting grounds on plant foliage.
The ladybug’s predatory success relies on crawling across leaves and stems where their prey congregates. They are not adapted to hunt and capture fast-flying insects. If insect prey is scarce, many ladybug species supplement their diet with plant pollen and nectar.
The Most Voracious Stage
The ladybug life cycle includes four stages: egg, larva, pupa, and adult. The larval stage is the most active and hungry. Ladybug larvae look dramatically different from the spotted adult, appearing as tiny, elongated creatures that resemble miniature alligators.
These larvae are black or gray, sometimes with orange or yellow markings, and are frequently mistaken for pests due to their unusual appearance. The larvae are voracious feeders, sometimes consuming their own body weight in aphids daily. A single larva can devour an estimated 400 aphids during its two to three-week development period before it pupates. This appetite allows a ladybug population to quickly control pest outbreaks, as the young insects cannot fly and must feed continuously near their hatching site.
Utilizing Ladybugs for Pest Control
Since ladybugs are ineffective against mosquitoes, their practical application in pest management focuses on plant-dwelling insects. To use ladybugs effectively, gardeners must create an environment that encourages them to stay and reproduce. This requires providing food and water while avoiding harmful chemicals. Broad-spectrum insecticides should be avoided entirely, as they kill beneficial insects indiscriminately and eliminate the pests that ladybugs need to feed on.
If releasing commercially purchased ladybugs, the timing and method of release are important for retention. Ladybugs are typically released in the late evening after the sun has set, as they are less likely to fly away in the dark. Immediately prior to release, it is helpful to water the garden thoroughly. The beetles are often dehydrated from transit and will seek out moisture droplets on the foliage.
To naturally attract ladybugs, gardeners can plant pollen and nectar sources such as:
- Dill
- Fennel
- Yarrow
- Sweet alyssum
Providing a reliable food source in the form of existing aphids or other pests is necessary. Adult ladybugs require a healthy protein intake to lay eggs. By meeting these needs, you can encourage them to settle, mate, and produce the next generation of highly effective, aphid-eating larvae.