Trichogramma brassicae is a minute parasitic wasp used to control caterpillar pests by attacking them at the egg stage—before they hatch and cause crop damage. Especially effective in cole crops and cool-climate plantings, this beneficial insect targets over 200 species of moths and butterflies, including armyworms, cabbage worms, loopers, borers, fruitworms, and hornworms. By preventing egg hatch, T. brassicae provides reliable, chemical-free protection for vegetables, orchards, vineyards, and field crops.
How It Works
Female wasps lay their eggs inside pest moth eggs. The developing larvae consume the contents, preventing caterpillar emergence. Parasitized eggs turn brown to black, serving as an indicator of success. Adults emerge in 7–10 days, continuing the cycle. Each female can parasitize up to 300 pest eggs during her 1–2 week lifespan. Effective control requires releasing T. brassicae at the first sign of moth flight, before larval feeding begins.
Targets These Pest Species
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Armyworms (Spodoptera, Pseudaletia)
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Cabbage worms, loopers, moths
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Cutworms (Agrotis, Peridroma)
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Corn earworm & European corn borer (Ostrinia nubilalis)
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Codling moth, oriental fruit moth
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Tomato hornworm
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Squash vine borer
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Leafrollers, webworms, bollworms
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200+ additional Lepidoptera pest species
Ideal Conditions
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Best for low-growing crops (e.g., broccoli, cabbage, kale)
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Temperature range: 70–90°F ideal for rapid development
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Emergence: 2–5 days after receipt (from cards)
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Full lifecycle: ~10 days (temperature-dependent)
Application Instructions
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Monitor pest flight using pheromone traps to time releases
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Release at first moth flight and continue every 7–10 days while moth activity persists
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Do not touch parasitized eggs on cards or tabs
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Place cards or tabs evenly throughout crop canopy; for bulk eggs, use release boxes or distribute in shaded areas
Release Rates
Where to Use
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Cole crops (cabbage, broccoli, kale, etc.)
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Greenhouses
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Orchards and vineyards
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Outdoor vegetable beds and row crops
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Container plants
Shipping & Storage
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Cards ship Mon–Thurs via 2nd Day Air (Overnight +$20)
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Bulk eggs ship Tuesdays only (order by Wednesday for next-week release; Overnight +$10)
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Processing time: 24–48 hours
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Storage: Keep at 80–90°F in a warm, shaded location until adults emerge
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Do not refrigerate; release immediately upon emergence
Quick Tips
✔ Time releases carefully with pest flight patterns for best results
✔ Ideal for cool-season and cole crop protection
✔ Use alongside Bacillus thuringiensis (Bt) for layered caterpillar control
✘ Not effective once caterpillars have hatched—apply early
