There has been plenty of rain this year since early spring. I have two
apples whose apples have split on the tree. I don't know what variety
they are, but they ripen in August or September and have thick skins.

My neighbor has three varieties that ripen in June and July, He has had
no splitting.

What causes apples to split while growing?

From: Stephen Throop
Newsgroups: rec.garden

What causes apples to split while growing?

Excess water perhaps-hard fruits like apples rarely split but some types may be
more prone thsn others