Pest profile

Cabbage Webworm

Hellula rogatalis · Lepidoptera: Crambidae[2]

Cabbage webworms can bore into the bud of cabbage and broccoli, killing it and preventing a marketable head.[1]

Cabbage webworm moth, a brownish-yellow moth with darker mottling, on a white surface
Cabbage webworm moth, a brownish-yellow moth with darker mottling, on a white surface. Photo: kcthetc1, public domain (CC0), via iNaturalist

How to identify it

  • Unlike other caterpillars on cole crops, the larva has a black head; its tan body has four brown stripes.[1]
  • Larvae hide in webbed pockets along leaf margins.[1]

Look-alikes

Look-alikeHow to tell them apart
Imported cabbagewormAnother cole crop caterpillar; the cabbage webworm's black head sets it apart.[1]

Where it lives

It's common along the Gulf Coast and southern Atlantic states and only rarely reaches Kentucky in fall.[1]

US map: public records from 15 states since 1990 (GBIF).

Biology and life cycle

Moths lay 300 to 350 eggs on plant buds; larvae hatch in about three days and feed in the buds before moving to outer leaves.[1]

Damage and signs

  • Damage begins as quarter-sized brown, dried areas on leaf edges; boring into the bud can cause side shoots or kill the plant.[1]

Health risk

It feeds on plants; UK Extension mentions no risk to people.[1]

Control

Prevention

Start monitoring when fall plants are set out; it isn't a problem on spring crops.[1]

Pesticides

Controls for other cabbage pests work if applied while larvae are small, before they spin protective webs.[1]

Common questions

What caterpillar has a black head on my cabbage?
The cabbage webworm, unlike other cole crop caterpillars.[1]
Why didn't my broccoli form a head?
Cabbage webworms boring into the bud can prevent a marketable head.[1]

Sources

  1. University of Kentucky Entomology (ENTFACT), “Cabbage Webworm (ENTFACT-315).” entomology.mgcafe.uky.edu/ef315 (accessed 2026-10-06)
  2. iNaturalist, “Hellula rogatalis taxon page (order and family).” www.inaturalist.org/taxa/210616 (accessed 2026-10-06)

Updated 2026-10-14. Built from sourced records. Spot an error? Tell us.