Prune barberry shrubs in the winter to shape the bushes. Cut out dead or damaged wood during the dormant winter season or during the summer months.
Barberry shrubs handle pruning well, so you can trim them any time of year. If you use the barberry shrubs as hedges, you may need to trim them a few times per year to maintain the shape. More intense pruning to rejuvenate the plant or remove a large section of dead branches is best done in the late winter months. Once the shrubs start growing again in the spring, you can lightly trim or pinch off new sprouts to shape the shrubs and encourage additional branching.