Hard Pruning Japanese Maple

[il Dublinese]

Hi everyone! A few years ago I planted a Japanese maple which had a nice shape with 3 primary branches. A couple of years after the central branch dried up and I had to remove it and I left 2 primary branches. One primary branch (the left one) has no secondary branches except at the top and at the base and is not developing much, unlike the right branch is growing in thickness (see photo 1).

To improve the shape of the tree I was thinking of doing a drastic pruning just above the base of the 2 primary branches where secondary branches and other branches in the stem formed a couple of years ago, which I would like to develop by replacing the 2 current main branches. Basically, I was thinking to cut most of the two main branches (red part of the image below) and leaving only the lower branches born at the base of the main branches and the other branches born from the stem recently near the 2 primary branches (green part of the image 2) hoping they can grow in a more harmonious way, also in height, compared to the current conformation of the maple.

What do you think? Does it make sense to do this pruning operation? Or is it better to do nothing so as not to damage the plant? Can other types of pruning be done to give a better shape to the Japanese maple now asymmetrical and bare in the middle? Thank you!

 

[Esther Knapicius]

I'd leave it alone.

 

[cpp gardener]

I would leave the right side alone and shorten the left side to just above the line of the wall in the picture. Wait a year and if that side doesn't get bushy enough, cut it where you have it marked.

 

[il Dublinese]

I would leave the right side alone and shorten the left side to just above the line of the wall in the picture. Wait a year and if that side doesn't get bushy enough, cut it where you have it marked.

ok. Makes sense. I just don't understand why to shorten the left side to just above the line of the wall. Why cut the branch in the middle far from the secondary branches?

 

[cpp gardener]

When it branches there it will balance the other side better and you might get more branching in between to fill in. You need some 'void' space to show what's behind the tree.

 

[il Dublinese]

Thanks a lot for the advice.

To avoid too much shock I'm considering cutting one branch one year and another the next, but I think I'll do the following:

1) I don't do anything for now at most, I give a little fertilizer as soon as the sprouts come out.
2) At the end of May/June when the maple already has leaves and the nymph is stable, I do a light pruning back to the top, in particular to the main branch on the left, hoping that this will stimulate the branch to place epicormic and twigs at the bottom.
3) After the foliage, in November, I drastically cut the two main branches that I proposed by putting mastic on the wounds.
4) Fingers crossed that next spring the maple is not dead and growing in width and height!