I hear some people say that they don’t like weeping Japanese maples (Acer palmatum ‘Dissectum’ and other cultivars) and my heart breaks. I feel that this can be one of the most beautiful trees with just a little work to enhance its form, but often they are left to their own devices and their beauty can be hidden by layers of branches.
Naturally these plants tend to form a thick flowing coat of branches and leaves, somewhat reminiscent of Cousin It from the Addams Family. In time they will have many layers with the innermost dying from lack of light. While they can still be attractive without pruning, I feel that the thick outer layer obscures from view the beautiful branching inside. The form and branching is what makes this plant so desirable throughout the year.
With some regular pruning you can have a stunning structural plant that is open to allow you to appreciate the foliage and branching, and it can easily be conformed to any size and be trained in any direction. Like most shrubs, they need to be pruned for aesthetic and functional purposes. I hate seeing contractors pruning azaleas, boxwood, holly and many other shrubs with gas pruners. While they might achieve the lollipop form they are seeking, it encourages a thick outer layer of leaves with no internal growth and a plant that must expand every year to survive.
Functionally, they need to be opened up to allow light inside so the inner branches won’t wither. Aesthetically, you want to accentuate the delicate branching and flowing form.
Last week, I helped a client prune a slightly overgrown and dense maple. The question I get most often is where do I start. For those who might be a little nervous, getting inside and pruning out the dead branches is a great place to start. Next, I look for branches that are going ‘against the grain’ or crossing the major flowing branches of the tree. The largest branches form a type of umbrella and they tend to flow out and down, and often branches form that go across this structure and they need to be pruned out.
Step back and see what has developed after this work. Always step back and look at your progress because it is best to come back and make another cut rather than regretting the loss of a branch you didn’t mean to cut.
After the dead and crossing branches are gone it is time to start looking at the major structural branches. Always start at the top of the plant and make a couple of bigger cuts rather than making lots of smaller cuts. The bigger cuts will produce the major structural changes you are looking for rather than small ones that will fill in quickly. The idea at the top of the umbrella is to develop a strong and interesting form to support the rest of the plant. It often means removing branches to accentuate a curve or decrease the congestion of multiple branching. Also, it can involve removing a branch that goes underneath and allowing a visual separation to create a layered effect.
The cuts you make will also dictate the future direction of growth. If you want your maple taller, then encourage branching on top that is pointing up, and lighten those branches by removing shoots pointing downwards. If you want a wider plant, then prune at a point where a branch is pointing outwards in the direction you want to expand.
It is pretty intuitive, you just need the courage to make the cuts necessary to enhance your beautiful weeping maple. Great words of guidance I learned years ago is to make few big cuts rather than lots of small cuts. I am not imposing my will on the plant, just opening it up to enhance its beauty. You can also come back later and make additional cuts. They are long-lived plants and pruning and care for them is a process.
Sometimes you might just make a few cuts and wait until next year to see how the tree responds. However you prune your maple, it is worth the effort to enhance one of the finest specimen trees available.