Willows bleed sap if you prune them while they are actively growing, so the best time to prune willows is in winter while the tree is dormant. Weeping willow pruning is also necessary after a storm. Cut branches that are broken or damaged with a pruning saw. Make the cut just below the break.
If you see dead wood, trim the limbs until there is only living tissue left. 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.
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.
The tree mostly has upright branches when young; as it grows, the branches bow to the ground, a habit that can be avoided by pruning the tree regularly. Never proceed with any tree work without first checking if there is a Tree Preservation Order (TPO) in effect. Look for future publications that cover the other willow species or you can ask us to write a guide for your particular tree. 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.