Petunia Pests: Caterpillars, Aphids, and Control Options

Petunias in Las Vegas show black dots on leaves, black larvae underneath, and green half-inch worms.

Pest Identification

• Green worms: Caterpillars (likely tobacco budworm or similar).
• Black dots/larvae: Could be caterpillar frass (droppings) or aphid colonies.

Control Strategies

1. Hand-pick caterpillars if few plants.
2. Bt (Bacillus thuringiensis): Effective but slow (weeks).
3. Fast-acting insecticide: Consult local garden center for approved products (spinosad, pyrethroids, etc.). Spray 2–3 times at few-day intervals.

Note

Chemical availability varies by region; always follow label for edible/ornamental use.

Expert insight provided by Melissa.