When it comes to tree and shrub pruning, some folks seem to abide by the axiom of “Prune all you want, it’ll grow back”. While in many cases this can be true (English laurel, ivy, wild blackberries), in even more cases, you might be doing irreversible harm. Some general rules of thumb:
Only use hedge shears on hedges, not on anything else. Hand shears are best on almost every other shrub. There is no healthy replacement for patient, hand selected cuts.
Don’t expect to undo 25 years of growth in one pruning session. You will only hurt the plant by making too large of cuts. Better to remove it or accept the size of the plant or tree. Make gentle reduction/ thinning cuts to reduce the mass of the canopy, according to the growth habit of that species. This will reduce the chance for wood rotting pathogens to invade the cut site.
Always remove dead, diseased and conflicting branches first. Dead branches are, well, dead. Disease on branches will always spread to other branches. Fungus prone species will always benefit from generous air flow-through. Redundant and rubbing branches just clutter things up and clog up air flow. You may not be happy with what’s left, but that is your true starting point for any additional thinning and shaping (or decision to remove the plant altogether).
Determine what fruit bearing wood looks like on any fruit tree. Some bear on older wood (apple), some on one-year old wood (peaches). This will determine your pruning approach on a variety of species. If you cut off the fruit wood every year, you will have no fruit.
Never leave a stub. Always cut back to a branch’s origin. With exceptions, trees cannot re-sprout in a healthy way from a stub. In some species, re-sprouting will not occur at all (stone fruits). Stubs that don’t re-sprout just die back and cause rotting problems.
While pruning, stand back and look at your work every so often. Look at the tree from where you see it most. Make yourself happy! Nothing like looking at that one sprout you missed for the rest of winter, because the tools are already put away.
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