Pruning permits free circulation of air and allows penetration of sunlight through the canopy. The most serious pest of the durian is the fruit borer, which at the larval stage, bores into and feeds on the fruit. Application of recommended insecticide such as BHC is encouraged. Another pest is the leaf cutter which can seriously defoliate young and older trees. Patch canker is the most serious disease.
Affected trees show bark decay, gummosis of the collar and stem collars causing dieback of branches.
The whole plant may eventually die and infect other plants. Control is mainly cultural by providing good drainage, removal of vegetation around the trunk and use of resistant root stocks. Affected trees are treated by painting or spraying Ridomil, a systemic fungicide. Durians generally bear one crop a year but may crop twice a year if influenced by the right conditions. Normally durian fruits are allowed to drop when they are fully ripe.