Harvest Maturity
The growth of the durian follows a sigmoid curve. Growth is very fast until the 13th week after pollination, after which it slows until the 16th week (112 days), when the fruit reaches maturity and falls from the tree. The fruit normally ripens two to three days after it falls. Fruit harvested from the tree is cut 15 weeks after anthesis (105 days). The skin of the durian shows little color change during ripening. As a result, ripeness is judged by changes in the fruit's smell or the hollow sound produced when its spines are tapped.

Durian maturity categories

• Fully matured: The fruit is fully matured when it has reached more than 90% physiological maturity. Fruits may or may not show signs of aril softening. If left on the tree, fruit might fall. If harvested, it will ripen to excellent eating quality. The subsequent storage life of such fruit is usually less than 3 to 4 days.
  
  
• Matured green: A matured green fruit has reached 80 to 90% physiological maturity and is considered commercially matured. The storage time for an "advanced" matured green fruit is about 5-8 days, and no more than 10 to 12 days for the "less" matured green. If harvested, the fruit will continue to ripen and complete the ripening processes to good and excellent eating quality.
  
  
• Immature (young): Fruits of less than 75% physiological maturity are considered immature. If harvested, the fruit may or may not be able to undergo climacteric processes and thus may not ripen normally. Although the aril may soften, its eating quality is normally inferior, and thus commands low commercial value.