American holly is often grown as a specimen bush in the landscape or with several planted together as a hedgerow. They have evergreen leaves and red berries that are often used as seasonal decorations. Fortunately, winter is an excellent time to prune American holly, so you can use their trimmings for decorations without causing harm to the plants.
Remove damaged, diseased or dead branches. Cut back all the way to the main stem.
Remove any branches that are growing or crossing over another branch. If two branches rub together, the bark could be rubbed off, which is an invitation for insects or disease to enter the plant.
Prune individual specimens of American holly in a roughly pyramidal shape. The lower branches should be longer than the ones above it. If you wish to prune the American holly to a smaller size, remove an equal amount from each tier of branches so the finished shape resembles a pine tree: smaller, shorter branches at the top with the lower levels of branches progressively longer. Do not remove the bottom level of branches; they are needed to support the weight of the snow-filled branches above them.
Prune a hedgerow of American holly so that the upper and lower branches are the same length. Do not prune lower branches shorter than the upper branches; the lower branches will not get enough sunlight and will die. For a hedgerow of American holly, the shape you're aiming for is similar to a severely pruned box hedge: all of the branches should terminate within the same vertical plane.