When and how do I prune fruit trees?
Fruit-tree pruning is an exception among early bloomers: With apples and the like, including ornamentals like crabapples, what you’re working toward isn’t as much the pretty flowers as an architecture and openness that can carry and ripen maximum fruit. I prune in late winter, knowing those are apple blossoms-to-be I am cutting off.
Every year, remove all the water sprouts or suckers—thin, whip-like wood that juts straight up from the main limbs but could never support any fruit—with a folding saw or running shears.
Then there’s the hard part: taking out big branches. Step back and evaluate the tree, or even better take pictures and digitally “black out” the branches you think the tree would eventually be better without. How does it look now, “without” them?
The basic idea is to open the center to allow light and air circulation, and also to lower the crown if possible. Never remove more than one-third of the tree’s live wood in any year. It will take at least three years, therefore, to accomplish what you imagine when you “pruned” the expendable parts of the tree out of the snapshot.
When removing large branches, first reduce the weight of the limb by cutting off half of it. See the 3-step cut answer, above.