Trimming ornamental trees is an important part of their maintenance, and correct and timely pruning will produce a healthy and vigorous tree. This maintenance task should never be ignored; trees may become overgrown, and in some instances weak. Pruning or trimming is not difficult once you understand the reason behind pruning, when to prune and how to trim/prune an ornamental tree.
Reasons to Prune
There are several reasons to prune your tree. One of the main reasons is to maintain the size of your tree within your landscape design; for instance, to keep it away from buildings, walkways and other plantings. Another reason is to remove any undesirable growth such as weak or overcrowded branches. remove dead, diseased or damaged branches for the health and appearance of the tree. It is also important to remove faded flowers and fruit clusters in order to promote flower buds for next year.
When to Trim Flowering Trees
When to trim ornamental flowering trees is dependent upon flowering, fruiting and growth habits of the tree. (Occasional trimming of a branch or two can be done at any time.) Ornamental trees that bloom before the end of June should be pruned after they have flowered. Since the flowering buds were produced the previous season, if you trim the tree before it blossoms you will remove all of the flowering buds, and the tree will not bloom. Other flowering trees that bloom after the end of June--when buds are produced during the springtime--should be pruned when dormant (winter or early springtime) before the buds form.
Keep all pruning tools sharp so that they make clean cuts; ragged cuts provide entry for disease. Use hand shears for branches up to ¼ inches in diameter. If you have branches that are up to 1 ½ inches in diameter, use lopping shears. Alternatively, use a pruning saw for anything over 1 inch in diameter. Use pole pruners for branches that are too high to reach with the loppers or hand shears.
Methods of Trimming
There are three methods or techniques that you will use when trimming or pruning. If you want to remove a few leaves you can just pinch them off by hand. "Thinning" is when you remove branches back to the trunk or back to a main branch. "Heading back" is when you shorten a branch back to a bud or to a lateral branch.
Pruning or Trimming Myths
Purdue University's Department of Horticulture lists several myths about pruning: pruning is difficult, plants will die if pruned at the wrong time of the year, all pruning must be done during the winter, removing a tree is a crime against nature, and all cut surfaces must be treated with tree paint.