🐉 Tomato Hornworm
How to identify
A fat green caterpillar up to 4 inches long with white V-shaped stripes along its sides and a harmless black 'horn' on its rear — intimidating, but it can't sting. You'll usually spot the damage first: stripped stems and big black frass pellets (caterpillar poop the size of peppercorns) on leaves below.
Damage signs
Hornworms defoliate with shocking speed — a couple of caterpillars can strip a tomato plant bare in days, then move on to the fruit, gouging green tomatoes. They prefer the tops of plants, so the damage appears suddenly overhead.
Non-chemical controls
- Handpick them — they're enormous, slow, and easy to spot once you learn to look for frass pellets and stripped stems; chickens consider them a delicacy.
- Hunt at night with a UV flashlight: hornworms fluoresce bright green under ultraviolet light, turning a chore into a glowing safari.
- Leave the ones carrying white cocoons alone — those are braconid wasp pupae, and the wasps inside will hatch to parasitize the next generation.
- Till the soil in fall and spring to destroy the large brown pupae overwintering underground.
- Plant basil and marigolds near tomatoes; they're reported to confuse the night-flying moths looking for egg-laying sites.
- Rotate nightshades to new beds each year so emerging moths don't find tomatoes exactly where they left them.
