Which plant should be pruned in fall after flowering?

• A. Peegee Hydrangea
• B. Pyramidal Arborvitae
• C. Mountain Adromeda
• D. Mountain Laurel

Answer: (A)

Pruning timing is guided by when a plant forms its flower buds. PeeGee hydrangea blooms on new wood, meaning the blooms come from the current year’s growth. After it finishes flowering, it’s common to prune to shape and control size, and doing so in fall is workable because the plant is moving toward dormancy and won’t be sacrificing next year’s bloom. Light, selective pruning after flowering helps keep the shrub compact and encourages a fresh flush of growth for the next season.

The other plants don’t fit fall-after-flowering pruning as well. Pyramidal arborvitae is a conifer that benefits from pruning in late winter or early spring to maintain its shape, not in fall. Mountain adromeda and mountain laurel flower in spring and set next year’s buds on the wood formed around that bloom; pruning after flowering is typically done soon after bloom in spring or early summer to avoid cutting off next year’s buds, so fall pruning is not ideal for them.