When it comes to growing squash vines in the vegetable garden, many organic gardeners can be divided into two groups: those that look forward to National Sneak Some Zucchini onto Your Neighbor’s Porch Night, and those who suffer from an infestation of squash bugs. These sucking and piercing insect pests can cause healthy vines to wilt overnight, and they’re also responsible for spreading the Cucurbit Yellow Vine Disease when they inject its virus into the plants during feeding.
Identify Squash Bug Damage
Squash bugs lay their bronze-colored eggs early in the season on the undersides of leaves of all kinds of squash, pumpkins, and some melons. The eggs, usually in clusters of 10 to 20, are about the size of a pinhead and placed carefully between the veins of leaves. After about two weeks, the eggs hatch into squash bug nymphs, identifiable by their orange heads and green abdomens. Over the next month, the nymphs grow into thumbnail-sized adults, with gray, shield-shaped bodies.
If an organic gardener is inspecting his vegetable garden regularly, he should catch the conspicuous squash bug at all stages in its life cycle under the leaves of the plants. If a squash vine shows sudden signs of wilting but no bugs are present, the gardener may consider a possible infestation involving the squash vine borer, which feeds on the plant stems from the interior.
Physical Control of Squash Bugs
The most effective, least invasive way to control squash bugs is to prevent them from hatching on their host plants. Gardeners can employ floating row covers when transplants are set out in the garden to prevent the mature bugs from laying eggs on the leaves. Gardeners must remove the row covers after flowers appear to allow pollinators to reach the plants. If some beetles manage to access the plants, it’s easy to flick their eggs off into a bucket of soapy water.
Safe Organic Pesticides for Squash Bugs
Gardeners who choose to use organic sprays on squash bugs should apply the natural pesticides early in the season, as the nymph stage is the most susceptible to these sprays. Gardeners can use insect soap to kill nymphs, but it’s essential to apply the soap to the undersides of the leaves where the insects congregate. Organic sprays that contain neem or pyrethrum also have activity against squash bug nymphs. Organic gardeners who aren’t squeamish can experiment with homemade “bug juice,” which consists of a slurry of water and the pests themselves applied to the plants.
Sources:
University of Kentucky College of Agriculture
National Sustainable Agriculture Information Service
Jamie McIntosh - Jamie has written hundreds of garden articles for the web, and is your guide to Flowers on About.com.
