That is the question.  Many years ago I asked Dr Cummings of the Cornell Fruit Breeding Program about whether or not to prune something.  His answer was: “Not pruning is almost always the wrong thing to do.  Pruning trees is probably the part of gardening that is the least understood and the most confusing for beginners.  There are many methods out there and it is something you almost need to see to understand well.  In addition we instinctively hate to amputate something that we have babied and gotten to grow!  However, leaving it unpruned is not doing yourself or the tree any favors.

Most fruit trees put their energy into the tips and keep growing long.  If these main scaffold branches (the ones that come from the trunk) are not cut back, very little secondary branching will occur.  This secondary branching provides most of the fruit crop and pruning back also allows for the development of a stronger branch.  Unpruned you will end up with a spindly tree that has leaves only at the ends of branches and minimal fruit (generally out of easy reach).

When you cut off the terminal end or last few buds, the growth hormone that was directed to the tip, now has to spread amongst the new end buds and branches are the result. While specifics are beyond the scope of this post, there are a few basic tips:

1.  Any vertical secondary growth from a branch is called a “watersprout”.  Cut these off as they will not fruit and will sap energy from your tree. 

2. Main scaffold branches on very young trees should be cut back by up to 1/3 if you have insufficient secondary branching. 

3. Central leaders should be cut back to encourage new scaffold branches higher on the tree. 

4. Scaffold branches should project radially around the tree and be spaced about 18”-24” above each other. 

A major goal in pruning is to get light to all parts of the tree for proper fruit development. Any suckers from the base should be cut right next to the trunk as these drain energy and provide nothing.

If your tree has not leaved out or is just emerging it is not too late to prune. Many places in the mountains are still cold enough that trees are just budding. The simple rule to remember is winter pruning stimulates growth and summer pruning stops growth.  So while your tree may get a new haircut, it will soon be much fuller and stronger as a result.