When is a good time to prune a lilac?
The general rule with flowering shrubs is to prune them immediately after they finish flowering each season. Most flowering shrubs, including lilacs, flower on second year wood which needs sufficient time to regrow if it's going to produce flowers the following season. Prune too late and next year's crop of flowers will be sparce. Fortunately, the error won't affect future flowering.
With lilacs, it's also necessary to pinch back their spent flowers to the first set of leaves before they set seed. This allows the energy of the plant to go into forming new growth instead of into seed production, resulting in a much better display of flowers next year.
When you're pinching back your lilac flowers, bear in mind that the growing tips responsible for next year's flowers are located at the point where that first set of leaves is located. Damaging these tips will impact next year's flowering, which is why you want to use your fingers to pinch the flowers back and not a clunky set of pruners.
If you have any questions or comments, please send them to me at vanessa@gardenmuse.ca.
Originally published in the Creston Valley Advance.
