What's eating my dracontium polyphyllum?

Dracontium polyphyllum, a dramatic tropical aroid with a single compound leaf, grows from a large tuber and is susceptible to slugs and caterpillars that attack the soft emerging leaf, mealybugs in sheltered axils, and fungus gnats when tubers sit in wet potting mix. Spider mites may appear in dry indoor conditions. Protecting the single emergent leaf is critical.

Significant damage to the single emerging leaf as it unfurls — ragged holes or entire sections consumed overnight. Apply ferric phosphate pellets around the pot or planting site before the leaf emerges; hand-pick at dusk.

White waxy clusters at the base of the petiole and in sheltered stem crevices; yellowing and sticky honeydew. Remove with alcohol-dipped cotton swab; spray with diluted neem oil; isolate the plant.

Holes chewed into the compound leaf leaflets; frass present near feeding sites. Hand-pick caterpillars; apply Bt spray on young larvae. In containers, use fine mesh to exclude adult moths.

Larvae in potting mix attack fine feeder roots on the tuber surface; adults hover around the pot. Allow top 5 cm of growing medium to dry; use Bti drench; sticky yellow traps catch adults.