The easiest way to trim established conifer hedges is by using a powered hedge trimmer to give a regular, even finish. Quick growing conifers will need about three cuts per year during the growing season, at roughly eight week intervals.
Inspect the hedge thoroughly before trimming it is to ensure there are no birds nesting within. It is an offence under the WILDLIFE AND COUNTRYSIDE ACT 1981 to damage or destroy the nest of any wild bird while it is in use or being built.
Trim the top of the hedge by holding the hedge-trimmer horizontally with both hands and using the string line as a guide. Wear protective goggles and gloves and make sure you have a firm footing on a platform or ladder.
Clip the sides of the hedge using the string as a guide. Hold the hedge-trimmer vertically and make long sweeping strokes to an even finish.
Remove the string guide before using the hedge trimmer to tidy up the top edges. Hold the cutting bar ata 45-degree angle.