You can trim the bushes to shape them from March through July, but O’Malley warns most pruning should stop by August. After shaping, the tender new growth can be injured by the coming winter. But ...
A second prune may only be necessary if you are growing barberry as hedging plants to keep them neat and formal. Deciduous types of barberry are best pruned during dormancy from late winter to early ...
If your tree or shrub flowers before June 1, prune it immediately after flowering. If your shrub or tree blooms after June 1, prune it the following year, in late winter or early spring, before new ...