What's eating my begonia gehrtii?

Begonia gehrtii is a rare cane-type houseplant susceptible to the usual indoor begonia pests — mealybugs and spider mites top the list. Its large leaves can also attract thrips. Consistent inspection of leaf undersides and axils, combined with good air circulation, keeps most problems manageable.

White cottony masses at stem nodes and leaf axils; honeydew secretions attract sooty mould. Remove visible colonies with alcohol-soaked cotton swabs; treat the whole plant with neem oil solution weekly for a month. Quarantine affected plants.

Fine pale stippling across large leaf surfaces; webbing on undersides in hot, dry conditions. Shower foliage thoroughly; apply insecticidal soap or neem oil spray every five to seven days. Keep humidity above 50%.

Silvery scarring and distortion on new leaves and any developing flowers. Prune badly affected growth, then apply spinosad or insecticidal soap sprays. Yellow sticky traps monitor adult numbers.