Ligustrums, what many gardeners call "privets," come in several different species and many varieties. Some are smaller shrubs and useful in the landscape as hedges or in home foundation plantings. Others grow much taller making them ideal for use as a privacy screen or 'limbed up" to form an attractive small tree.
Pruning Ligustrum
Ligustrum do not require pruning, however respond well to it for shaping purposes or to form shaped hedges or very attractive small trees.
When To Prune Ligustrum
Light pruning of Ligustrum to remove a stray or damaged branch can be performed any time of year. Shearing of Ligustrum can be performed any time of year, however, to avoid damaging new growth that emerges after pruning, I recommend ceasing pruning two months prior to the average first frost date in your area. Heavy pruning to reduce the size or to tree form your Ligustrum should be performed in late winter, while the plant is dormant.
Selective Pruning of Ligustrum
Use a sharp pair of bypass hand pruners to selectively remove stray or damaged branches. Make your cut at a point along the branch just above the main form of the plant.
Pruning Ligustrum for Hedges
When using hedge trimmers for a formal shaped hedge, lightly and regularly shear the plant to desired shape several times throughout the growing season.
Note: If you're forming a hedge that you want to be full with foliage to the ground, remember to keep the bottom of the hedge a little wider than the top. This allows sunlight to reach the bottom of the hedge and helps to prevent leaves from shedding due to lack of sunlight.
Tree Forming a Ligustrum
Taller growing varieties of Ligustrum are very easy to tree form. Wait until your shrub is about 4 feet tall to begin the tree forming process. At that time, start at the base of the plant by removing the lateral branches growing from trunk(s). Continue removing branches until you've reached the desired height and are satisfied with the appearance. Before making your cuts, make sure that the removal of a branch will not spoil the shape of the canopy. Also, between each cut take a few steps back to take a look at your plant.