What's eating my hoya lambii?

Hoya lambii is a Bornean species prized for its large, textured leaves and grown as a houseplant. Mealybugs are the dominant threat — the corrugated leaf surface provides hiding spots. Spider mites can proliferate in heated rooms with low humidity. Inspect the backs of the distinctive ribbed leaves carefully during routine watering.

White cottony wax tucked in the deep ridges of the leaf surface and at stem nodes; honeydew and sooty mould follow. Use a thin-tipped alcohol swab to reach the leaf ridges; spray the whole plant with neem oil or insecticidal soap weekly for 3–4 weeks.

Pale stippling across the large leaf surface with webbing between ridges; leaves lose their deep colour and may drop. Increase humidity, shower the foliage to dislodge mites, and apply insecticidal soap or neem oil every 5–7 days.

Small waxy or hard bumps along stems and the main leaf veins; slow sap drain causes yellowing and stunted growth. Physically remove with an alcohol-dampened brush, then apply horticultural oil fortnightly until infestation clears.