Hi - I planted an apple tree sapling this spring. It has already spent a year in a pot at our old house and is about 5 foot high at the moment. I'm aware I'm slack and done nothing so far to prune it into the 'correct' shape. It now has a two or three long, whippy branches and is laden with fruit. I've been doing some research and can see that I should have pruned it when it was dormant into a Y shape etc to encourage a healthy tree. But I didn't.
So - is it too late to start now? Will I damage the tree if I attack it during its growing season? Help!