This article is part of our Organic Pest Control Series, which includes articles on attracting beneficial insects, controlling specific garden pests, and using organic pesticides.
These extremely small, gnat-sized wasps lay their eggs inside the eggs of other insects, where the young trichogramma develop as internal parasites. Because the trichogramma’s life cycle is very short — just seven to 10 days from egg to adult — populations can grow rapidly.
Trichogramma larvae eat insect eggs, especially those of cabbage worms, codling moths, European corn borer, diamondback moths, and other moths and butterflies. Insect eggs that have been parasitized by trichogramma wasps turn black or metallic blue. Adult trichogramma wasps consume flower nectar and sugary substances produced by special glands on the leaves and stems of many garden plants.
Trichogramma wasps are so tiny that observing them in the open garden is often impossible. However, scientists have found that the flower nectar from buckwheat and sweet alyssum enhanced wasp health and reproduction in lab experiments.
Trichogramma wasp eggs are available commercially, and are much less costly compared with other purchased beneficial insects. Sold as parasitized eggs attached to small paper cards, they are placed outdoors at night, usually hung from branches. Organic fruit and nut growers often purchase trichogramma wasp eggs and hang the cards when codling moths, pecan nut casebearers, or other pests are in egg-laying mode. On vegetable farms, trichogramma wasps are sometimes introduced to control European corn borer in corn, peppers or potatoes. Trichogramma wasps are often used to control several important pests of cotton.
Whether you want to learn how to grow and raise your own food, build your own root cellar, or create a green dream home, come out and learn everything you need to know — and then some!LEARN MORE
At MOTHER EARTH NEWS, we are dedicated to conserving our planet's natural resources while helping you conserve your financial resources. You'll find tips for slashing heating bills, growing fresh, natural produce at home, and more. That's why we want you to save money and trees by subscribing through our earth-friendly automatic renewal savings plan. By paying with a credit card, you save an additional $5 and get 6 issues of MOTHER EARTH NEWS for only $12.95 (USA only).
You may also use the Bill Me option and pay $17.95 for 6 issues.