What's eating my amorphophallus decus-silvae?

Amorphophallus decus-silvae, a spectacular Indonesian species with a single compound leaf, is most at risk from spider mites in dry greenhouse conditions and mealybugs sheltering in the thick petiole sheath. Slugs can annihilate the emerging shoot. Fungus gnats colonise persistently moist mix around the large tuber. Because there is only one leaf per growing season, any damage is highly significant.

Pale stippling and bronzing across leaflets; fine silk webbing on undersides indicates established infestation. Maintain high humidity; spray neem oil or insecticidal soap on undersides every 5–7 days until resolved.

White waxy deposits inside the petiole sheath and in crevices at the leaf base; honeydew and stunted growth. Target each colony with 70% isopropyl alcohol swab; treat whole plant with neem oil; repeat fortnightly.

The tender emerging shoot can be entirely consumed before it opens — a season-ending loss for a one-leaf species. Lay ferric phosphate pellets around the emerging shoot; use copper tape on pot rims; hand-pick at night.

Larvae tunnel into roots and feeder root hairs on the large tuber; adults hovering indicate overwatering. Let the top layer of potting mix dry between waterings; apply Bti drench; use yellow sticky traps.