Dogwood shrubs, such as red twig dogwoods, are not to be confused with dogwood trees. While both shrubs and the trees belong to the same genus: Cornus, the shrubs will never become trees. There are two species of dogwood shrubs: Cornus alba, which is the Tatarian dogwood, and Cornus sericea, which is the Redosier dogwood. Both species are much alike in their cultural needs.
If you do nothing else to care for your Dogwood shrubs prune them. A once-a-year pruning in late winter is essential to maintaining the bright colors of the twigs, which is what these shrubs are prized for. Your goal in pruning Dogwood shrubs, such as the red and yellow twigged dogwoods, is to remove old stems that have lost their brilliance that will be replaced by new, brightly colored stems. Since the younger branches bear the brightest color, that is precisely the growth you want to encourage.
Pruning Dogwood Shrubs
Annual Pruning
Every year, in late winter, you'll want to remove about a third of the old, most faded stems from your Dogwood shrub, cutting them back to the ground. Also cut out any damaged or dead stems. This method will encourage more new, brightly colored stems to emerge when the plant emerges from dormancy in spring. If you want to control the height of the shrub, the stems you left alone can be shortened by one-third to one-half their height
Rejuvenation Pruning
If your Dogwood shrub has become overgrown and unsightly, or just looks burnt out, in late winter you can cut back the entire shrub to about 10 inches above the ground.