Best Time To Prune Willows: How To Prune A Willow Tree

Willow trees need special pruning that begins while the tree is young. Proper pruning helps establish a graceful growth pattern and prevents damage as the tree grows. Let's find out how to prune a willow tree.

Willow Tree Pruning

Willow trees are more durable and have a better shape if you do most of the pruning and shaping while the tree is young. Pruning willow trees properly while they are young and easier to prune means you probably won't have to make major changes in the tree's structure when it is older and more difficult to prune. 

Willow trees bleed sap if you prune them while they are actively growing, so the best time for willow tree pruning is in winter while the tree is dormant. Make sure you have the right tools for the job before you begin. Hand pruners are the tool of choice for small twigs and thin, whip-like stems that are no more than one-half inch (1 cm.) in diameter. 

For stems up to 1 1/2 inches (4 cm.) in diameter, use long-handled loppers. The longer handles give better leverage for cleaner cuts. Use a saw for anything larger.

Shaping a Young Tree

When trimming a willow tree sapling, the goal is to develop a strong central leader, which will later become the trunk of the tree. You also want to remove branches that are too close together as well as weak branches that are likely to break when they mature and become heavy. Here are the steps in shaping a willow tree:

• Remove any damaged or broken branches. Make the cuts where the branch attaches to the trunk.
• Choose a tall, upright stem at the top of the tree as a central leader, and remove competing stems.
• Remove branches that grow up instead of out. A narrow crotch angle between the branch and the trunk makes it likely that the branch will break as the tree grows and the branch becomes heavy.
• Remove crowded branches. The result should be branches that are evenly spaced around the tree.
• Remove the branches from the lower part of the tree when the trunk reaches a diameter of 2 inches (5 cm.).

Pruning a Mature Tree

Mature willow trees don't need a lot of pruning. The tree will heal faster with fewer disease problems if you remove broken branches and those that rub against each other. If you shorten the branches, always cut just beyond a leaf bud or twig. Don't allow branches to grow on the lower part of the tree. 

If you catch new growth soon enough, you can stop it by pinching it off or rubbing it with your fingers. Willow trees grow quickly, and this makes them susceptible to wind breakage. Maintaining a little space between branches allows good air circulation and reduces the amount of breakage. 

Remove suckers arising directly from the ground by cutting them off at ground level or below. Suckers drain energy from the tree because they grow very quickly.

Can You Prune a Willow Tree to Shorten Weeping Branches?

Weeping willow trees develop long branches—sometimes long enough to reach the ground. While this gives the tree a graceful shape, it may not be practical in the landscape. 

The long branches can become an obstruction to foot traffic and make landscape maintenance more difficult than it has to be. You can shorten them to any length as long as you cut just below a leaf bud.