Evergreen viburnum are grown for their extensive foliage, flowers and berries. There are 150 species of viburnum, including evergreen, semi-evergreen and deciduous varieties. The best time to prune the evergreen viburnum is when it is dormant. Although evergreen viburnums need little pruning to maintain their shape, periodically you should prune any diseased or broken branches or any that disrupt the tree's framework. Sometimes these trees grow into areas that are not conducive to their survival, such as underneath power lines or against fences. Choosing the right branches and tools is essential for pruning evergreen viburnum.
The best time to prune your evergreen viburnum is late summer to mid-autumn. Pruning in the spring causes excessive sap bleeding, which makes wounds difficult to heal and invites pests.
Use pruning shears to remove stems no thicker than a pencil, loppers for branches that easily fit the stem's girth in the bite and a pruning saw for cutting thick portions of the tree.
Locate the young evergreen tree's leader---its main stem. If there is more than one leader, choose the strongest to be the main leader and prune off the rest. Cut close to the tree's main stem without harming the bark.
Prune any damaged or weak branches. For a young evergreen, pinching side shoots encourages dense growth.
Inspect the tree for any signs of disease or pests. Evergreens commonly succumb to rust, wood rot, verticillium wilt, mealybugs and weevils. Before every cut, dip your pruning tool in a solution of 10 per cent denatured alcohol and water to avoid spreading disease. Making slanted cuts also discourages fungal disease by allow water to roll off the cut surface.
Remove any branches that impede outdoor structures or other vegetation. To cut the branch, make a cut close to the branch collar. The branch collar is the slight swelling at the base of the stem. You can make large cuts more manageable by performing a series of cuts up to the branch collar.
Clip the ends of branches that are growing more on one side to encourage a well-balanced tree.
Avoid severely pruning mature evergreens---they heal slowly, especially in tropical climates.