Few trees are more charming than Japanese maples with their deeply cut, starry leaves. If your Japanese maple won’t leaf out, it’s very disappointing. Leafless Japanese maple are stressed trees, and you’ll need to track down the cause. Read on for more information about the possible reasons you see no leaves on Japanese maples in your garden.
Japanese Maples Not Leafing Out
Trees not leafing out when they’re supposed to almost certainly cause alarm in homeowners. When this happens to trees prized for their foliage, like Japanese maples, it can be especially heart wrenching. If winter has come and gone, you look to your Japanese maples to start producing their beautiful leaves. If, instead, you see no leaves on Japanese maples in spring or early summer, it is clear that something is amiss.
If your winter was particularly brutal, that might explain your leafless Japanese maples. Colder than normal winter temperatures or bitterly cold winter winds can cause die back and winter burn. This can mean that your Japanese maple won’t leaf out.
Your best course is to prune out dead or damaged branches. But be careful because some branches and shoots look dead but aren’t. Do a scratch test to look for green tissue. When trimming back, prune to a live bud or a branch union.
If you see only leafless Japanese maple in your garden when other trees are in full leaf, check to see what the leaf buds look like. If the buds do not seem to be processing at all, you’ll have to consider the worst possibility: Verticillium wilt.
The nutrients that leaves produce during the summer are stored in the roots. In spring, the nutrients rise into the tree via sap. If your tree has a problem getting the nutrients back up to the branches, the problem could be Verticillium wilt, an infection in the xylem layer that blocks sap.
Prune out a branch to see if Verticillium wilt is the cause of your Japanese maples not leafing out. If you see a ring of dark on cross section of the branch, it is likely this fungal disease.
Unfortunately, you cannot save a tree with Verticillium. Remove it and plant only trees resistant to the fungus.
Water stress can also be a reason for leaves not growing on Japanese maples. Remember that these trees need water not just in summer, but in dry springs and falls as well.
Another reason for leaves not growing on Japanese maples can be root related. Girdled roots can cause leafless Japanese maples. Your tree’s best chance is for you to cut some of the roots, then be sure it gets enough water.