The red barberry (Mahonia haematocarpa), native to the United States, is a common landscape shrub that has bright red or purple leaves. Like the standard barberry variety, the red version is also covered with sharp thorns along the entire length of the stems. The shrub, which reaches 3 to 8 feet tall at maturity, often becomes scraggly if not pruned. Severe annual pruning encourages healthy, vigorous growth in the red barberry bush.
Wait until midsummer or fall, when the red barberry shrub stops flowering for the year. Put on long sleeves, pants and thick gardening gloves before beginning the pruning process.
Look at the top of the red barberry and find one of the longest branches, which is typically one of the oldest ones. Trace the branch back to the ground and cut it as close to the ground as possible. Use hand pruners if desired, but loppers are longer and prevent injury from the thorns.
Repeat the process to prune off a quarter to a third of the remaining longest stems on the red barberry.
Identify any stems that have no foliage on them, meaning they are dead, and prune them at the surface of the ground.
Cut back the tips of any stems that have grown into other plants, hang down on the ground or invade walkways. Cut them back to any length, making the cut a quarter-inch above a set of leaves.
Rake up all of the red barberry clippings and throw them into the trash or compost.
Things You Will Need
- Long sleeves and pants
- Gardening gloves
- Hand pruners
- If desired, you can also prune red barberry in early spring, but the plant will not produce any flowers that growing season.
- A more severe form of pruning is cutting back the red barberry stems all the way to the ground in the fall.