I have an overgrown shrub in my backyard that I’d like to prune. Can you tell me how to do it?
If your shrub has never been pruned, you’ve got your work cut out for you. My first piece of advice would be to forget trying to make up for many years of neglect by giving your shrub an extreme pruning this year. As a general rule, you never want to remove more than one-third of a plant’s branches in a single year since removing too many branches can weaken the plant, making it more susceptible to disease and insect infestations.
Instead, inspect your shrub, looking for any branches that are broken, diseased, or just plain dead. Once you’ve removed those, look for any branches that are crossing (or touching) other branches or angling back towards the centre of the plant and remove those. You also want to remove any suckers or water shoots. Those are the poker-straight branches that stick straight up from either the roots (suckers) or branches (water shoots) of a shrub.
Depending on how much wood you removed during these first steps, that may be all the pruning you’ll be able to get done this year. Next year, start your pruning adventure by standing back and taking a look at your shrub's overall branching pattern. Each species has an ideal shape and structure. If you don’t know what a prime example of your particular shrub looks like, put down your pruners and look it up in a gardening book, on the Internet, or even in a nursery catalogue. Once you know what your shrub is supposed to look like, you can set about removing any branches that don’t conform.
Often when people say their shrubs are overgrown, they aren’t just referring to a tangle of unkempt branches, but also to the size of a plant that is now pressing into walls, covering walkways or threatening to take over the neighbor's yard. Branches can often be selectively removed to reduce the size of the plant without impacting its overall look. The worst thing you can do is to start clipping the ends of the branches, creating a lopsided monster of a shrub. Remove branches at the trunk or at crotches, but never, ever be tempted to shear the tips.
People who prune shrubs for a living often spend as much time standing back and looking at a plant as they do making cuts. There is a good reason for this. One bad cut can destroy the look of a shrub faster than a propane torch. With careful consideration, the right cuts usually make themselves apparent.
A quick note about pruning equipment: Three basic tools are involved in pruning, including hand pruners for cutting branches up to a half-inch thick, loppers for branches up to two inches thick, and pruning saws for branches over two inches. Try to avoid using carpentry saws on live wood. They weren't meant for it and can needlessly damage the shrub in a way that a pruning saw won't.
If you have any questions or comments, please send them to me at vanessa@gardenmuse.ca.
Originally published in the Creston Valley Advance on July 12, 2007.
