Kill the pest, not everything
Bt (Bacillus thuringiensis var. kurstaki) is a naturally occurring soil bacterium that produces a protein toxic only to caterpillar larvae when ingested. It does not harm bees, ladybugs, earthworms, or humans. It is approved for organic gardening.
Apply Bt to leaf surfaces where caterpillars are feeding. It degrades in sunlight within a few days, so reapply after rain. Other Bt varieties target specific pests: Bt israelensis for mosquito larvae, Bt tenebrionis for Colorado potato beetle.
Row covers and netting
Lightweight row covers draped over plants exclude flying insects (cabbage moths, flea beetles) without blocking light or water. This prevents the problem before it starts. Remove covers when plants need pollination (cucumbers, squash).
Prevention first, intervention last
Healthy soil produces healthy plants that resist pests better. Crop rotation, companion planting, and encouraging beneficial insects (ladybugs, lacewings, parasitic wasps) reduce pest pressure before you need any intervention. Chemical controls, even organic ones, are the last resort, not the first.
- Bt: kills caterpillars only, safe for bees and humans
- Apply to leaf surfaces, reapply after rain
- Row covers exclude flying pests without blocking light
- Healthy soil and crop rotation reduce pest pressure naturally
- Intervention is the last resort, not the first
- UGA Extension — Integrated pest management for home gardens.