What's eating my longan?

Longan shares most pests with lychee. The longan stink bug and lychee erinose mite are the twin headline threats — the mite damages flush growth and the stink bug causes fruit drop. Fruit borer and mealybugs also affect clusters at harvest. Sulfur at bud burst and mesh bagging of fruit clusters are the first-line controls.

Adults and nymphs suck sap from shoots and fruitlets; fruitlets drop in large numbers; older fruit shows brown, dried flesh at the injection site. Destroy egg masses on leaves; hand-knock adults into soapy water in early morning; targeted pyrethroid spray when nymph numbers are high; preserve egg parasitoids by avoiding broad-spectrum insecticides.

Rust-brown velvety felt-like patches on new longan leaves; distorted leaf flushes and reduced growth if severe. Apply wettable sulfur or miticide at bud burst; remove and destroy badly infested shoots.

White cottony colonies on panicles and fruit stalks; honeydew and sooty mould contaminate the thin-shelled longan fruit. Neem oil or insecticidal soap on panicles before flowering; use sticky ant barriers on the trunk to remove ant protection from mealybug colonies.

Larvae tunnel through the longan pedicel into the aril; no visible external damage but frass-packed galleries inside harvested fruit. Fine-mesh fruit bagging at early fruitlet stage; registered insecticide applied at fruit set; prompt harvest and removal of fallen fruit.