The tree will heal faster with fewer disease problems if the broken branches and those are removed. You'll want to get those clippers out at the end of winter. Pruning weeping willow in winter allows you to cut the tree when it is idle. It also makes willows in good condition before they start their spring growth.
Weeping willow should only be pruned in late winter and early spring, when the tree is in its dormant period. This is because willows, like most trees, bleed sap if pruned during their active growth period. When the sap is exposed, it attracts insects, which bring with them spores of fungi and bacteria, which can cause disease. The time to achieve a lasting effect on the shape and structure of the plant is when the tree is young.
Crossed or crowded branches should be removed. Low branches should also be removed, if desired, when the tree is young. This is best done by removing one or two branches a year, for a period of a few years, until the necessary authorization is obtained. As the tree ages, pruning every three to five years will keep it in good shape.
As the tree grows, the help of a professional may be needed. Willows are quite responsive to pruning, says Bluestem Nursery, as they produce vigorous new growth soon after being cut because they have dense and extensive roots. Plants can be pruned at any time of the year. If you prune in late summer or early fall, the cold of winter may damage new, tender shoots.
Because of such a possibility, it is better to prune a willow tree at the end of winter, when it is still dormant, or in early spring, when it is ready to start a new growth. Look for future publications that cover the other willow species or you can ask us to write a guide for your particular tree. Willows are more durable and have a better shape if you do most of the pruning and shaping while the tree is young. The fact that willow is prone to numerous diseases and pests is another reason why a qualified arborist should really take care of the tree on a regular basis.
When pruning a young willow tree, the goal is to develop a strong central leader, which will later become the trunk of the tree.