To maintain a well-shaped hedge, you must prune and train it diligently. Ideally, you should begin trimming your hedges to the desired shape when they're still young. The way you go about pruning a hedge depends mostly on its age. Young hedges are cut differently than those that have reached three years or older. The right tools are also essential. If you have smaller hedges, you can get away with using loppers or pruning shears alone. You'll need to invest in a good power trimmer for larger hedges, however.
Cut all branches back half their length during the first and second years. Do not cut back the main stem until the hedges have reached their desired full height. Use heavy-duty pruning shears, loppers or a power trimmer to cut your hedges. Trim evergreen hedges in autumn or the spring before the new shoots appear.
Cut your hedges to make the sides slope inward as they go up, like a slightly rounded triangle shape. You can begin this shaping in the hedge's third year. This will prevent the lower part of the hedge from losing its leaves because of a lack of sunlight.
Trim your hedges at least once each year after they're fully grown. Start by cutting the sides, and then move on to the top.
Trim only the new shoots each year after you've created the desired shape. This way, you'll maintain the shape while at the same time enticing more buds on the remaining wood to develop and create a bushier hedge.
Tap the face of the hedge with the back of a rake after you're finished with the heavier cutting. This will help to shake out any twigs that may be folded back inward. Trim off any twigs that spring out.