Why Do Oranges Split Open on the Tree?

Cause

• Oranges splitting on trees in a common disorder of navel oranges, and is referred to as navel orange split. The disorder is not caused by a pathogen, but is the result of environmental factors. There is no chemical control strategy for the problem.

Symptoms

• Navel oranges begin to split on trees between September and November, starting at the navel ends. The cracks are either shallow and short or wide and deep, exposing the fruit flesh within. Fruit commonly splits when the skin or rind does not expand as rapidly as the water and sugar are transported to the fruit. The fruit consequently bursts open under the pressure.

Management

• Water and fertilize trees regularly to avoid fluctuations in growth environment. Time-released fertilizers are a better option than a large fertilizer application once or twice a year. Though split oranges are edible, they are insufficiently ripe, and drop prematurely from the tree.