Trimming A Walnut Tree: How To Prune Walnut Trees Properly

Person Sawing A Large Walnut Tree Branch
prune walnut
(Image credit: DLeonis)

Walnut tree pruning is important for the tree’s health, structure, and productivity. Walnut trees (Juglans spp.) make very nice shade trees, are excellent timber specimens, and also produce delicious nuts for eating by humans, birds, and squirrels alike. Keep reading to learn how to prune a walnut tree.

Pruning Walnut Trees

Trimming a walnut tree properly is vital to your investment. When you are developing a young walnut tree, you are developing its structure. You need to decide how high up you want the scaffold (side) branches on the trunk.

  • For harvesting nuts, you might start your scaffold branches as low as 4 ½ feet (1.5 m.).
  • For a shade tree, you might start your side branches at 6 to 8 feet (2 m.) in the air.

When your new walnut tree is too short to start developing scaffold branches, cut back any little side branches to 6 inches (15 cm.) long. Leaving these short branches for a few years encourages trunk strength and vitality, yet doesn’t rob too much energy from the trunk. Once your tree is large enough to start guiding the long-term scaffold branches, you can start cutting off the little stub branches below. It is best to remove the little stub branches before they grow over ½ inch (1 cm.) in diameter. The tree can seal off pruning wounds much more easily when they are smaller. Walnut tree pruning requires careful observation and judgment. Develop potential scaffold branches that are evenly spaced around the trunk. Trimming a walnut tree also involves annually removing damaged branches, crossed over or rubbing branches, and any branches that want to bend back toward the center rather than reach outward. Additionally, walnut tree pruning involves making sure that all side branches remain subservient or lower than the height of the central leader. In these situations, simply shorten the competitive side branches back to a tertiary side branch.

What’s the Best Time to Prune Walnut Trees?

The best time to prune walnut trees is the later end of the dormant season when the trees are still out of leaves. This way you can easily see the form of the tree and you are not cutting away any new growth that appears in spring. Make sure you clean and sterilize your hand pruners and pruning saw beforehand, so you don’t spread disease. Sharpened tools ensure clean cuts too. Trimming a walnut tree should not involve ripping or tearing the bark from dull tools. If you need to remove a larger branch, perform a jump cut to prevent the weight of the branch from tearing away the outer bark of the trunk as the branch separates from the tree. Jump cutting involves three steps.

  • First, cut halfway through the branch from the underside just outside the branch collar.
  • After that, you want to completely cut off the branch further out, 1 to 3 feet (31-91 cm.), on the limb.
  • Finally, you will cut the remaining stub just outside the branch collar.

Walnut tree pruning is an annual event even when the tree is mature. Investing some time and energy into proper walnut tree pruning will yield a tree that is strong, productive, and attractive to view.

Karen Boness

Karen Boness is the founder of Wild Willow Design, an Australia-based company that specializes in ecological landscape design.