What's eating my dieffenbachia 'tropic snow'?

Dieffenbachia 'Tropic Snow' is a popular large-leaved houseplant frequently attacked by spider mites and mealybugs, especially in heated indoor environments. Its broad, cream-variegated leaves give mites lots of surface area to colonise. Leaf-wiping, regular inspection, and maintaining humidity above 40% are the best preventive steps.

Yellow or bronze stippling across the large leaves; fine webs on undersides; leaves may wilt and curl in severe cases Wipe leaves top and bottom with a damp cloth; spray insecticidal soap or neem oil every 5–7 days for three to four treatments; raise humidity

White cottony deposits in leaf axils, on stems, and at the growing point; honeydew drips and sooty mould may follow Remove with 70% isopropyl alcohol on a cotton swab; apply neem oil spray weekly for 4–6 weeks; isolate from other plants immediately

Soft green or brown insects clustered on new shoots and undersides of young leaves; curled, distorted new growth Knock off with a strong water spray; apply insecticidal soap to all leaf surfaces, especially new growth; repeat weekly until clear

Larvae in soil damage fine roots; adults are a nuisance; young or recently repotted plants may decline unexpectedly Let the top inch of soil dry between waterings; use yellow sticky traps; drench soil with Bti (Bacillus thuringiensis var. israelensis) solution