Spring-Flowering Shrubs

• Examples of spring flowering shrubs include azaleas, clematis and weigela. These shrubs flower before or shortly after producing foliage. They form the flowering buds for the following spring during the summer months after blossoming. These shrubs require pruning immediately after the flowering cycle completes. Pruning later in the year trims away the new flower buds and prevents the bushes from producing their full bloom in the spring. Minor pruning to remove winter damaged wood in late winter doesn't inhibit flowering and helps improve the health of the shrub, but major pruning takes place in early summer once the plants lose their blossoms.
  
  

Summer-Flowering Shrubs

• Shrubs that flower in summer, like butterfly bushes and gardenias, usually form their flower buds in late spring after they finish leafing out. These shrubs respond best to late-winter or early-spring pruning performed while the plant is still dormant. Trimming in fall after the shrub completes flowering forces a flush of tender new growth that can't tolerate winter cold, causing damage to the shrub. Pruning once new growth begins may trim away the developing flower buds. Early spring pruning forces new growth and more flower bud production on these shrub varieties.
  
  

Foliage Shrubs

• Deciduous and evergreen foliage shrubs that don't flower tolerate pruning in both summer and spring. Perform major pruning in early spring when the plants are still in winter dormancy or semi-dormancy. Trimming the shrub before it awakes fully later in spring prevents shock to the plant. Summer pruning to help control the shape of the shrub doesn't cause damage to the plant, but pruning too late in the summer or fall may cause tender new growth more prone to frost damage.
  
  

Hedges

• Both foliage and flowering shrubs are sometimes trained into a hedge. Formal hedges require frequent pruning to maintain their size and shape. Severe pruning occurs in late winter when the shrub is still dormant. Frequent pruning continues from late spring until late summer to maintain the shape of the branches as they put on new growth. Flowering hedges experience their first annual pruning at the time specified for spring- or summer-flowering varieties, then pruning continues as needed for the remainder of the summer season. Some flowers are removed during maintenance pruning when flowering plants are used for hedges.