Bud pinching Japanese Maples

In the spring, with healthy Japanese maples, bud-pinching is a common technique to keep internodes short on refined trees. It is a simple procedure, and needs to be performed about daily as Japanese maples are waking up in the spring.

The earlier you can identify the 2nd node and remove it, the shorter the internode will remain. In this example, I’ve waited about a day too long, but it helps illustrate the process.

Here is the extending new shoot:

Here is a markup showing the leaves in the 1st in blue, where to pinch out the second node in a yellow X, and the resulting length of the halted internode:

This tree is growing stronger on the top and left, and slower on the lower right, so careful attention will be required to keep up with the lower right side, as shown in the background below.

A couple weeks later, the maple is still growing, and I had a chance to pinch back more of the shoots.

The result is a lot of tips removed, and the profile is improved, but the density is still the same.

After:

I will continue feeding, and in June, I’ll partly defoliate the tree to encourage back-budding. Meanwhile, I’ll keep a close eye out for wires starting to dig in.

Repotting a Japanese Maple

I didn’t get around to repotting this one last year, and it was the first time I skipped a year repotting it in probably 15 years, so I wasn’t looking forward to wrestling it free, and working the roots all the way back. However, it was pretty weak last year, and so the roots weren’t too crazy. Here are some shots of the process, which took about 90 minutes.

Unpotted:

Pot cleaned and new drainage mesh applied. 3rd generation Yamaaki. I love this pot with this tree, but the clay is developing small chips around the tie down holes, and one foot. The tree may also be ready for the next size up soon. This one is 19″ wide, and a 20″ would work. But the color is fantastic with the fiery red spring foliage.

First round of combing out the roots, and finding the tie down wire:

Once the wire is removed, it becomes a bit easier to comb out the root ball. I used a hose to remove most of the soil:

With most of the soil gone, the first round of trimming is around the circumference.

Comb everything outward from above.

Then repeat it on the bottom. Before:

After:

Notice how the roots are all radiating outward from the center now? Order from chaos!

Then I returned to working on the topside, combing everything outward, removing roots that were too thick, or growing up or growing down

Continuing around the nebari:

Back:

Finally, settled back into the pot. I chose to raise the planting height just a bit more this year to expose more of the base. It is widening nicely, but still has a few areas that need to fill in; most notably the one right in front. Those areas will not fill in when exposed to air, so it’s best to raise the tree a little at a time, and not before it’s ready.

Wired in:

Soil worked in:

Watered, and finally top-dressed with some fine sphagnum moss to keep the shallow roots from drying out:

More thread-grafting on an Arakawa Japanese Maple

The primary branches on this tree were made by thread-grafting, and the tree itself was made from an air-layer of nursery stock I bought in 2008. So this tree is pretty artificially developed. However, to keep growth dense and movement present with trees, sometimes this is the only way to go. So long as the result is convincing, the means don’t matter.

The trouble with this tree is that the left trunk has a long span with no branches on the right side. In time, the right trunk sill fill in the lower part of the space, but the left trunk does need a branch somewhere along this span:

Ideally it will be between two left branches, creating an alternating branch pattern…somewhere around the blue circle, on the outside of a bend:

I spent a couple years growing out a long branch to use for a thread graft. The right time to perform this work is just before buds swell in late winter.

First, I verified the shoot would make the bend into the spot I planned to thread graft. Check.

Drill the hole in the opposite direction the graft will be threaded. The exit side tends to be messy, while the starting point tends to be cleaner; and it is important to have intact cambium close to the graft.

Thread the shoot through the hole, careful to not knock off buds going through, and orienting the buds so they emerge close to the trunk. This will allow options and keep bifurcation close to the trunk, rather than starting a branch on a long internode.

Here, 3 buds (circled) and a 4th internode (squared) were threaded through. Notice how close the first bud is to the trunk?

Next, cut a small branch to use as a wedge to secure the graft tightly to the edge of the hole, and seal up both sides with cut paste.

End result: