Typically, witch hazels (Hamamelis spp.) need little pruning since they naturally develop into upright, vase-shaped shrubs to very small trees. The midwinter to early spring flowering display is more prolific if consistent reductive pruning of last season's growth takes place after the blooming ends, according to Chris Lane, author of "Witch Hazels." This annual pruning also helps keep the plants at a smaller size, particularly welcome in gardens that are not spacious.
Cut off all suckering shoots from the base of the witch hazel's trunk in late fall once the leaves have dropped away. Make the pruning cut with your hand pruners 1/4 inch above the attachment to the main trunk, or even with any surface roots if growing far from the trunk base.
Enjoy the flowering display of the shrub from winter to early spring. If you do see any damaged or dead branches during the winter resulting from cold or heavy snowfall or ice storms, prune them off as needed. Make the pruning cuts 1/4 inch above a lower, healthy branch or dormant bud.
Reduce the new growth of all branches back to only two buds on the previous season's growth. Do this in early spring once the flowering wanes but before the buds swell to reveal leaves. According to Lane, the previous season's growth will be at the ends of all branches and typically void of any flowering. Examine each branch and look for two healthy lower buds on these tip branches. Make the pruning cut 1/4 inch above the second lowest bud on this youngest twig growth all over the shrub.
Look through the shrub once all the branch tip pruning for any structural problems, such as rubbing branches or awkward and errant branches that are growing into the center of the plant. Make pruning cuts 1/4 inch above a dormant bud, a lower branch junction or nearly flush with a main trunk stem.