When should I prune my shrubs?

FAQ
Question: 

When should I prune my shrubs?

Answer: 

The proper time to prune deciduous and evergreen shrubs is determined by the plant’s growth habit, bloom time, and health or condition. 

Spring-flowering shrubs, such as lilac and forsythia, bloom in spring on the growth of the previous season.  The health or condition of the plants determines the best time to prune spring-flowering shrubs. 

Neglected, overgrown spring-flowering shrubs often require extensive pruning to rejuvenate or renew the plants.  The best time to rejuvenate large, overgrown shrubs is late winter or early spring (March or early April).  Heavy pruning in late winter or early spring will reduce or eliminate the flower display for 2 or 3 years.  However, rejuvenation pruning will restore the health of the shrub. 

The best time to prune healthy, well-maintained spring-flowering shrubs is immediately after flowering.  (Healthy, well-maintained shrubs should require only light to moderate pruning.)  Pruning immediately after flowering allows gardeners to enjoy the spring flower display and provides adequate time for the shrubs to initiate new flower buds for next season. 

Summer-flowering shrubs, such as potentilla and Japanese spirea, bloom in summer on the current year’s growth.  Prune summer-flowering shrubs in late winter or early spring.  The new growth produced by pruned shrubs will bloom in summer. 

Some deciduous shrubs don’t produce attractive flowers.  These shrubs may possess colorful bark, fruit, or foliage.  Prune these shrubs in late winter or early spring before growth begins. 

Prune evergreen shrubs, such as juniper and yew, in early to mid-April before new growth begins.  Light pruning may also be done in mid-summer.