When to prune plants in a garden depends on the particular type of plant. Later winter through early spring is a good time to prune fruiting and flowering plants. Some plants, such as spring-blooming trees, require pruning immediately after flowering. Other plants require regular pruning to remain healthy.
Evergreen plants do not need pruning, but if you want to make them fuller, prune them when they are still young. Most perennial plants require pruning before and after the growing season. Prune berry plants and fruit trees during the dormant season, late winter through early spring. This is also a good time to prune vines, shrubs and flowering trees.