What and When to Prune

When the snow flies, many gardeners put away their tools and take a few months off from the garden. Some pruning, though, is a good idea to do before the ground thaws.

Since fallen leaves leave the architecture of trees highly visible, late winter is a perfect time to prune your trees. Use a nice winter day as an opportunity to look for crossing or broken branches, which can usually be removed. Making these cuts in frigid temperatures keeps menacing insects and diseases at bay, giving your favorite tree enough time to heal before spring.

But for the rest of the plants in your garden, cleanup and cutting back are tasks best reserved for early spring. Leaving plants in their natural, dormant form provides habitat and food for creatures such as native bees and birds. Plus, leaving plant material protects and insulates the crowns of your plants, especially those that are less hardy, such as Buddleja lindleyana (Butterfly Bush), Vitex agnes-castus (Chastetree), and Hibiscus moscheutos (Hardy Hibiscus).

General Timing Rules for Cutback

  • Perennials and grasses should be trimmed in the spring before new growth starts.
  • Summer- and fall-blooming shrubs and vines bloom on new wood and should be pruned in early spring.
  • Roses should be pruned in early spring. Wait to prune climbing or one-time blooming roses until after they flower.
  • Trees should be pruned in late winter or early spring.
  • Spring-blooming shrubs such as lilacs bloom on old wood (the previous year’s growth) and should be pruned after they bloom but no later than the 4th of July.

Itching to get back into gardening before the snow melts? Stop by the Garden for Learn on Saturdays, our winter lecture series, to stay up-to-date on trends and tips for the upcoming gardening season. The series runs on Saturdays January-March from 10:30 a.m. to 12:30 p.m.