PestsUrgent — act today
Caterpillars on Cannabis (Budworms)
Cannabis caterpillars — usually corn earworms or tobacco budworms — bore INTO buds and eat them from inside. By the time you see damage, they're already eating your harvest.
What it looks like
- ●Small holes in leaves (early)
- ●Dark crumbly frass (poop) in bud crevices
- ●Wilting buds with brown rotten spots
- ●Small green worms inside buds when you inspect
Quick diagnostic checks
1BT (Dipel, Thuricide) is the gold standard — safe and effective
2Hand-pick any visible caterpillars
3Cut out any bud with frass visible — rot spreads fast
Causes ranked by likelihood
1. Outdoor grows are primary target
Most commonSigns
- ●Growing outdoors
- ●Moths visible at dusk
Fix
- ✓Apply Bacillus thuringiensis (BT) spray weekly from pre-flower
- ✓BT is safe for plants and only kills caterpillars
- ✓Inspect buds daily during flower
⚠️When to worry
Always. Caterpillar damage turns into bud rot within days. Can destroy an entire outdoor harvest.
Gear that prevents this problem
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