Native to central and western China, the leatherleaf viburnum (Viburnum rhytidophyllum) becomes a large, coarsely textured evergreen shrub 10 to 15 feet tall and equally as wide. Dr. Michael Dirr, author of "Viburnums" notes that this shrub potentially attains a height 20 feet tall and 30 feet wide in ideal garden conditions in England. Nonetheless, leatherleaf viburnum is a shrub for spacious landscapes where winter low temperatures don't drop below minus 23.3 to minus 26.1 degrees Celsius, which kills the buds and stems. Generally, viburnums grow with a naturally good structure and shape. They don't require much pruning. Pruning must retain the beauty of this shrub's large, lustrous and crinkled leaves, otherwise it begins to look unattractive.
Examine the overall condition of the leatherleaf viburnum shrub in early spring once winter cold and frosts no longer threaten. The leaves naturally droop in cold weather. Excessive cold or drying winds browns and kills leaves, and some branch twig tips and flower buds. Once spring arrives, those branches and leaves that perished from the previous winter will be evident.
Prune away all dead or diseased wood, using hand pruners. Make the pruning cut 1/4 inch above a lower living branch junction or pair of dormant buds or green leaves. Remove dead and diseased tissues anytime of year they are encountered, but early spring is ideal since new growth quickly responds and develops after pruning.
Refrain from more pruning on this shrub species until after it completes its flowering in mid- to late spring. The flower buds look like fuzzy brown cauliflower heads on the tips of branches. Pruning before these buds open diminishes the spring floral display and subsequent production of colourful berries later in summer and fall.
Trim back errant or problematic branches on the shrub in late spring or early summer to shape the shrub. Make the pruning cut 1/4 inch above a lower pair of leaves or branch junction to reduce the branch length to your needs and design taste.
Cut off suckering shoots from the base of the shrub's trunk, if any are present. Make the cut 1/2 to 1 inch above the soil line or flush with the shrub's trunk, if that's where the long, scraggly suckering stems originate. If you want the shrub to become larger or fuller, do not prune away suckers.
Viburnums do not need intensive and extensive pruning--only tidying and mild shaping to create a nice plant and prevent branches from rubbing into building facades or becoming hazardous across sidewalks.
Avoid using shearing blades on the large leaves of leatherleaf viburnum. It causes irregular tearing of the leaves that tend to brown and look shredded and sickly weeks later. Don't prune past midsummer. Regrowth shouldn't be underdeveloped and killed back by fall frosts. Plus, the fussy flower buds are already formed for next spring. Don't remove them with an ill-timed pruning in late summer or fall.