Natural Garden Pest Control
Natural garden pest control: ladybugs are a gardiners best friend for natural pest control. The busy little insects and their larvae are aphids natural enemies!
If you come across a ladybug in your flower or vegetable garden don’t tell her to “fly away home”. She and her counterparts, of which there are 450 known species in North America alone, are very beneficial insects to have in a garden. Ladybugs, sometimes called “ladybird beetles”, eat 50-60 aphids per day. They also eat other varieties of harmful insects like mealy bugs, leaf hoppers, mites and other soft-bodied garden pests. Even the ladybug larvae are beneficial. They require large numbers of aphids to sustain themselves and to progress from pupae to adult ladybug.
Ladybugs are vibrant and very identifiable insects and have a variety of different markings. The most common colors are red or orange bodies with black spots. Other species have white or yellow spots or are completely black with no spots at all. The larvae, too, are vibrantly colored, most often blue with orange or black stripes. Ladybug beetles are never larger than 1.2 centimetres.
The majority of ladybug species are carnivores, that is, they feed only on other insects. Their favorite prey is the aphid. Some ladybugs will eat only a certain type of aphid while others aren’t quite so particular. In years when aphids are not readily available ladybugs will eat moth
or beetle eggs, thrips, pollen and nectar. Sometimes they even feed on their own kind.
The ladybug is a very valuable natural enemy. The popular “convergent ladybug”, eats her weight in aphids every day and her young larvae need twice as many as they rapidly grow. This species is favored by many farmers. Convergents are collected by agricultural supply distributors and then sold to farmers for natural aphid control. An Australian species, the Vedalia, is used by citrus growers in California to get rid of the cottony-scale insect. Once an aphid colony has been eliminated, the ladybugs will move on to new hunting grounds and search from morning to night for food.
Ladybug adults overwinter, large groups hibernating in places like protected buildings, under rocks or bark, or beneath dried leaves or garden litter. Once it’s warm enough in the spring the ladybugs emerge from their shelters and immediately go in search of prey and good egg laying sites. Female ladybugs lay from 20-1000 eggs over a 1-3 month period. Eggs are always left in close proximity to an aphid colony to assure that the larvae have adequate food once they hatch. Each female lays from 10-50 eggs per day, depositing them in clusters of 3-20 on the undersides of leaves or shrubbery. Once the young hatch they will attack the aphids and consume as many as 400 per day. The larvae go into pupae stage after 3 weeks and 2-5 days later an adult ladybug appears.
If you want to keep ladybugs in your garden there’s a few things you can do to improve your backyard habitat:
1) keep moisture levels high. Ladybugs prefer surroundings with high humidity or continuous access to water droplets. Spacing your plants closer together and more frequent watering cycles are good ways to guarantee higher humidity.
2) make sure you have an abundance of nectar producing flowering plants in your garden. You might even want to try an artificial substitute like hummingbird food.
3) if you find hibernating adult ladybugs in your garden or around your house, leave them alone. Once disturbed there’s a chance they might be attacked by predators or parasites.
Vegetable and grain crops, legumes like beans and peas, strawberries, some fruit tree varieties, all benefit if a colony of ladybugs decide to move in and feed on aphids and other harmful insect pests. So remember, if you see a brightly-colored, busy little ladybug in your garden, then ask her to stay. Both you and she will benefit.