A deciduous shrub that reaches a height of up to 15 feet if left untrimmed, a privet hedge is commonly used for borders or privacy purposes. This perennial hedge does not drop its leaves in the winter but does so just before the onset of spring. Depending on personal taste, trim your privet hedge from mid spring to mid autumn, or after every eight weeks throughout the summer, to maintain its shape and size, and prevent it from spreading too much, specially if near a walkway, drive or building structure.
Insert a stake as tall as your desired height of the hedge after you trim it into the soil at each end of the hedge. Knot string at the top of a stake and extend it to the other to serve as a guide while you trim. Pull it taut so it does not droop.
Thin your hedge by removing 1/3 of older stems with loppers. This encourages good air circulation and allows sunlight to penetrate the interior stems and reach the lower branches.
Trim off stubborn leaves and branches that bounce right out of the string using sharp, long-handled pruning shears. Starting at one end of the hedge, grasp the shears firmly and make sharp, quick cuts to trim wayward foliage off.
Walk along the hedge as you continue trimming it, and work slowly so you do not miss any section. Cut directly above any Y-shaped stem that divides into two parts.
Trim the short sides of your privet hedge in proportion with the long sides.
Collect all clippings in a large plastic bag, tarp or wheelbarrow and dispose of appropriately.
Step back and review the hedge. Remove any wayward branches you missed. Hold the trimmers parallel to the foliage at the top and sides and make sharp cuts to trim any excess foliage off. Remove the stakes and string.