What's eating my white dendrobium?

White Dendrobium (Dendrobium formosum) is particularly vulnerable to scale insects on its hairy pseudobulbs, where the surface texture helps pests anchor and hide. Mealybugs gather at cane nodes. Thrips can damage the large white flowers. Inspect the hairy sheaths closely — scale can hide beneath them and go undetected for long periods.

Shell-like bumps on pseudobulbs and cane sheaths; weakened canes and yellowing lower leaves Use a soft brush with methylated spirits to dislodge scales; follow with monthly neem oil spray

White woolly deposits at cane nodes and inside leaf sheaths; stunted new growths Remove with an alcohol-dampened cotton swab; treat the whole plant with insecticidal soap fortnightly

Silver-streaked or bronzed petals; dark frass dots visible on white flowers; blooms drop early Remove and dispose of affected blooms; apply spinosad-based spray or blue sticky traps near flowering plants