Barberry doesn't shear well, so prune individual branches back into the bush to encourage new growth to arch gracefully. Evergreen wintergreen barberry (Berberis julianae), hardy in U.S. Department of Agriculture plant hardiness zones 6 through 9a, may be pruned from late winter through early spring. This fast-growing shrub shoots up to 4 feet tall and spreads even wider.
Its branches arch gracefully, but if you prefer a more formal look to your hedge, shear it in spring after flowering. It is recommended that you prune the shrubs after they have fruited, during fall or winter.
Dead woods should be removed during summer months, and the bushes should be pruned in the period between mid winter to late winters, i.e., before spring. According to the University of Minnesota Extension, barberry bushes should be trimmed at the time of treelopping.buzzted Reading Time: 5 mins. Jun 01, Barberry can be cut back hard and will recover although it will be slow.
You cannot simply shear the plant to “size” as it will open up to just a stemmy appearance. You will need to either cut Estimated Reading Time: 2 mins. Tie nonproductive branches together and cut the old clump down to the ground with a long-handled lopper. On deciduous varieties, tie target branches before leaves drop.
When shrubs grow too big to manage, tie up branches and prune all clumps down to 1 inch tall. Barberry will regrow 1 to 2 feet in the first year.