Bay Weekly

Mother Nature’s Pest Control

By Maria Price

     Before you spray your garden for those pests that seem to sample everything you like to grow, learn who the good guys are, as they will be your allies in the long run. The less insecticides you use, the more a natural balance of predators will occur. There are many good bugs out there ready to help. It may take some time, as they need to be encouraged. 

     Integrated pest management is a method of identifying pests, evaluating the damage, finding the specific pest and then using the proper spray or trap — or in some cases competing insects.

     Among the easiest good bugs to spot are ladybird beetles or ladybugs. They’re mostly red but also come in orange, gray and black with and without black spots. Adult ladybugs can eat 50 aphids per day, which are a common pest of roses and tomatoes. Ladybugs lay their yellow-orange, oval-shaped eggs on the underside of leaves. The alligator-shaped ladybug larvae that hatch can themselves eat 30 to 40 aphids per day.

     To encourage ladybugs in your garden, try planting tansy, angelica or scented geraniums.

     Don’t confuse ladybugs with black-spotted, rusty-orange Colorado potato bugs, which prey on potatoes and tomatoes. They’re a pest you want to manage, often by picking them off plants and dropping them in a soapy water solution.

     My next best garden friends are lacewings. I call them the fairies of the garden because their iridescent wings are bright green, lacey and beautiful. Some species have large golden eyes. Adults lacewings like to reside on flowering plants, where they feed on insects. But the most voracious predators are their larvae. Known as the psychos of the insect world, they look like half-inch-long alligators. 

     Lacewing larvae impede aphids, caterpillars, mealybugs, leafhoppers, insect eggs and white flies by sucking them dry. 

     Lacewings are one of the most effective predators you can buy from commercial sources and have a good reputation for sticking around in your garden.

     Hoverflies or syrphid flies are my other friends in the garden. I’ve noticed that many people are afraid of them because they look like yellow-jacket bees. They have yellow-and-black-striped bodies, but they have only one pair of wings whereas bees have two pairs. They are also smaller than a yellow-jacket and a little flatter. These predatory flies get their name from their habit of hovering over flowers for pollen and nectar. 

     Hoverflies are one of the best pollinators for the garden. The larvae, which look like small sluglike maggots, consume aphids at a rate of one per minute. The adults help by laying their eggs among groups of aphids.