The best time to prune shrubs is late winter or early spring, before flower growth, or, for spring flowering shrubs, after the flowering is complete.
To determine which branches can be removed without changing the natural shape of a shrub, remove dead wood, weak growth, and broken and diseased branches. Suckers should be removed from the origin of growth: the root. Dig away the soil and cut the sucker where it is attached to the root. Remove as many of the oldest branches as necessary – cutting at ground level. Every three years, remove approximately one third of the branches to rejuvenate a shrub.
Shrubs can be kept symmetrical by trimming the longer branches to suit the natural shape. Starting at the top and working down is the best way to shape a shrub.
Summer and fall-blooming shrubs flower on new wood – branches that have been produced the current season. Some examples are: Butterfly bush, Rose of sharon, Crepe myrtle, Summersweet and Abelia. These shrubs should be pruned in the spring before new growth begins.
Some winter hardy shrubs die back to the ground each year. In the spring, cut off all dead branches to about six inches from the ground, leaving at least two buds on each stub. New branches will grow from the roots as well as from the buds. For those winter-hardy shrubs that do not die back to the ground, remove some of the oldest branches to encourage new growth.
