Pruning Japanese maples should be done in late winter before the leaf buds start to open. You can also prune Japanese maples after the leaves have fully opened in late spring early summer. A big thank you to Joseph at Thomas and Son’s Tree Care in Portland, Oregon for marking up my pictures and educating me on how to prune my blood good Japanese maple. Make sure whenever you are pruning a Japanese maple, not to remove any more than 25 to 30% of the live wood of the tree per year. It is a good id