3 Things to Know About Pruning Lilacs and Forsythia

Prune right after blooming Spring-flowering shrubs set buds the previous summer. Cut them back as soon as the flowers fade, not in fall or winter.

Time of day doesn’t matter The plant does not care if you prune at 8 AM or 4 PM. Any cool-ish part of the day is fine, but pruning at noon won’t hurt it.

Avoid late-winter pruning Pruning in late winter or early spring removes this year’s flower buds. That is the real mistake, not the hour you choose to work.