How to identify
- Pale green caterpillar that arches into a loop when it crawls
- Thin white lines along the sides
- Large irregular holes between leaf veins
Damage: Defoliation and contaminated heads, similar to cabbageworms.
Control methods
- Use floating row cover on spring brassicas.
- Hand-pick; look under leaves for pale eggs.
- Encourage parasitic wasps by avoiding broad insecticides.
What products to use
We list product types and what to check on the label — not brand rankings, prices, or “we tested” claims. Always follow the label for your crop, and prefer the least disruptive option that works.
Bt (kurstaki)
When: Young loopers on foliage
Look for: Labeled for loopers/cabbage caterpillars on vegetables