Tomato Hornworm Identification Guide
A large green caterpillar with white diagonal stripes and a curved rear horn, often found munching tomato foliage.
Read the full Tomato Hornworm encyclopedia entry →
Key Visual Features
- Thick, large caterpillar that can grow to 3-4 inches (7.5-10 cm) long at full size.
- Body is bright green, closely matching the color of tomato plant leaves and stems.
- Eight V-shaped or diagonal white stripes run along each side of the body, angled slightly toward the rear.
- A single dark, curved horn-like projection sits near the rear end of the body (on the eighth abdominal segment); the horn is often black, blue-black, or dark reddish depending on the individual.
- Small black or dark spots may be present near the base of each white stripe.
- Adult form is a large, heavy-bodied gray-brown moth (the five-spotted hawk moth) with a wingspan of 4-5 inches and yellow-orange spots along the abdomen.
Where and When You'd See It
- Found on tomato, and related plants such as pepper, eggplant, and potato, primarily during the warm growing season from early summer through early fall.
- Caterpillars feed on foliage and stems, and are most active and visible in the early morning or evening when temperatures are milder.
- Because of the strong green camouflage, they're often noticed by the trail of stripped leaves and dark droppings left on plants rather than the caterpillar itself.
- Adults (the moths) are most active at dusk and after dark, often seen hovering near flowers.
Similar-Looking Bugs
- The tobacco hornworm is nearly identical but has straighter, parallel white stripes (rather than V-shaped) and a red or reddish horn rather than black; the two are best told apart by stripe shape and horn color.
- Other large green caterpillars, such as some swallowtail larvae, lack the rear horn entirely and instead may have eyespots near the head.
- Smaller green loopers or inchworms move with a distinctive arching "looping" gait and are much smaller and thinner than a hornworm.
Quick ID Checklist
- Large green caterpillar, up to 4 inches long.
- Eight diagonal white side stripes.
- Single curved horn near the rear end.
- Found on tomato-family plant foliage in summer.
- Adult stage is a large gray-brown hawk moth active at dusk.
Frequently asked questions
How do I tell a tomato hornworm from a tobacco hornworm?
Look at the side stripes and horn color: tomato hornworms have V-shaped diagonal white stripes and a dark horn, while tobacco hornworms have straight parallel stripes and a red horn.
Why is the caterpillar so hard to spot on the plant?
Its bright green color and stripe pattern blend closely with tomato foliage and stems, so it's often easier to notice chewed leaves or droppings first.
What does the adult moth look like?
The adult is a large, heavy-bodied gray-brown hawk moth with a wingspan of several inches and a row of yellow-orange spots along its abdomen, often seen hovering at dusk.
Does every hornworm have the same color horn?
No, horn color varies by species and individual, ranging from black or dark blue on tomato hornworms to reddish on tobacco hornworms.
Tomato Hornworm identified by the community
Recent Tomato Hornworm finds identified with Bug Identifier.
