Of the four seasons, winter is the best time to prune trees. I usually start pruning my tropical trees wintering over inside and take the opportunity with a warm day to tackle my compact fruit trees scattered around my one-acre garden.
Now don’t wait until the tree is full grown. I completely forgot I had planted a semi-dwarf pear tree near my driveway until it started to bloom some 30 years later. Now I am trying to trim octopus-like branches while keeping enough branches I can reach to bear pears. If you start pruning and shaping when trees are young, trust me they are much easier to shape.
Most fruit tree pruning guides will offer confusing descriptions of the desired shape so here’s my short cut; keep the center of the fruit tree open to allow sun, and encourage 3 main center branches to form a cup. Prune remaining branches to grow outwards and strong to hold fruit. It’s tempting to keep more branches for flowering and setting fruit but if the branch is too weak, the weight of the fruit may break the branch so keep a few strong branches instead of a lot of weak ones.
For flowering trees such as redbuds and dogwoods, prune when flowers are fading. For the rest, prune in late winter when trees are still dormant. Don’t prune in fall when some viruses are at their strongest and can contaminate trees through their open cuts.
Some other tips:
Main side branches should be at least 1/3rd smaller than the trunk diameter. Encourage branches to form angles that form “10 o’clock” and “2 o’clock” angles within the trunk.
Don’t prune up any more than 1/3rd of the tree’s total height and never, ever, top a tree.