Tomato Hornworm

The tomato hornworm is the larval stage of the five-spotted hawkmoth, Manduca quinquemaculata, a member of the sphinx or hawkmoth family Sphingidae. Despite its intimidating size and prominent tail horn, it is entirely a plant-feeding caterpillar with no ability to sting.

This caterpillar is one of the most recognizable garden insects in North America due to its large size and close association with tomato plants and other members of the nightshade family. Its adult form, the five-spotted hawkmoth, is a large, fast-flying moth that hovers at flowers much like a hummingbird, making it an ecologically valuable nighttime pollinator.

• Thick, cylindrical caterpillar reaching up to 4 inches long at full growth.
• Bright green body marked with about eight pale V-shaped or chevron-like white markings along each side.
• A prominent, curved, dark bluish-black horn-like projection at the rear end, which is soft and harmless despite its fierce appearance.
• Small black or dark spots often present near the base of each white marking.
• Lookalike: nearly identical to the tobacco hornworm, distinguished mainly by the shape of the side markings and the horn color; the tobacco hornworm typically shows seven straight diagonal white lines and a red horn.

Found throughout North America wherever tomato, pepper, eggplant, and other nightshade-family plants grow, including home gardens and agricultural fields. Caterpillars are most commonly seen from mid to late summer, feeding heavily on host plant foliage.

The caterpillar feeds voraciously on the leaves and occasionally fruit of nightshade-family plants, using its green camouflage to remain remarkably well hidden among foliage despite its large size. It has no stinger and its horn is a soft, non-functional structure used only as a visual deterrent to potential predators. The adult five-spotted hawkmoth feeds on nectar from deep-throated flowers at dusk, hovering in place much like a hummingbird and acting as an important pollinator.

The tomato hornworm undergoes complete metamorphosis. Eggs are laid singly on the undersides of host plant leaves and hatch within about a week into tiny green caterpillars that feed and molt through five stages over three to four weeks. Mature caterpillars burrow into the soil to pupate in a dark brown case, emerging as adult moths after two to four weeks, or overwintering as a pupa underground through the colder months, with one to two generations occurring per year depending on climate.