Prune shrubs whenever there are diseased, dead or broken branches. Prune branches that grow from under or near the ground, branches that cross and branches that grow upright vigorously on the shrub's side branches or trunk.
Shrubs must also be pruned at certain times of the year to maintain their health. The annual schedule for pruning varies from variety to variety. Wait until late spring to prune shrubs that bloom early in the spring to avoid cutting off buds. Prune shrubs that bloom in the summer in the winter; cut these down to the ground and they still bloom. Prune roses that bloom once a year after they are done blooming, and clip repeat bloomers to reshape the shrub or in early spring. Prune shrubs that do not bloom and those that are leafy in the late fall or winter. Prune hedges frequently earlier in the growing season.