I recently began adding worm castings around the base of my 2 year old Washington Navel Orange and the fruit is enormous size, like grapefruit. The problem is that the inner fruit is outgrowing the skin and busting out while the skin is still green. This may be related to the castings but also it has been hot in Southern California and I have some yellow markings on the leaves which I attribute to the heat. What can be the problem?
I would add that although all varieties of citrus can experience fruit splitting, Navel oranges are particularly susceptible to splitting. - Millet
I recently had a couple Daisy mandarins that split overnight after a rain (prior to that it had been at least 3 weeks since the last rain). I probably should have watered a couple times.
Yes it is common when the flesh expands quicker than the peel can expand. I just had a bunch of my variegated oranges split after a prolonged rain.
