The life and troubles of Deshojo #2

I finally decided to have one place to tell you the story of the second Deshojo I had in my life. The first one was, as far as I can remember, an innocent victim of the sun about 25 years ago.
It's mostly a way to remind me not to repeat the errors I made and spot an issue I already met in time. Feel free to correct me any time since I'm not an expert, just an enthusiast of trees and Nature in general.
This is still my favorite JM because of the colors it exhibits every season but it's a very delicate and demanding tree, at least when it's in my hands.
March 2015
I got the tree in March 2015 from a local (German) online shop, standard import from some Asian country.
At the beginning of May I pruned the longer shoots. My reasoning was that if I got too long internodes on the new shoots I would have to cut the whole new growth anyway so I was trying to keep the ones with short internodes and reduce the others.
Now I know that pruning (too many) new branches the tree is still developing might take some energy off it and weaken it. I'm much more conservative now with late Spring pruning although the issue of long internodes still exists.
To be continued...


Anacortes, WA
New growth is always coral red. The time to prune any acer palmatum is after a growth spurt when it stops extending and all the new shoots and foliage have hardened. This is roughly May and August, but easily recognized on deshojo by there not being any (or extremely few) coral red leaves. In this state, the foliage is its most productive, so wait a bit so that the tree can build strength. If left be, the tree will again start to produce shoots --> coral red leaves start to appear again at the branch tips = time to prune.

Some things I've noted with all acer palmatums are that the first internode of the season is the shortest. The branching angle is the widest for shoots from the first spring buds. The angle is narrower for the shoots produced from May pruning and the narrowest for shoots released by an August pruning. So, if you want nothing but the shortest possible internodes, your tree will progress no faster than one internode per year (growing season).

If you are trying to build thickness, don't prune in May nor August. Let the branch run and only prune just after leaf fall and/or as buds swell in spring. Always leave a pair of visible buds on a branch in fall pruning.

I have shin deshojo, which is not the same as the old deshojo, though both have that brilliant coral red foliage. It has a habit of also producing a bit of fine twiggy branching with no intervention. I have thus far failed to note when/why this happens. You should observe whether your deshojo behaves similarly - it could be of value to building ramification later on.
The time to prune any acer palmatum is after a growth spurt when it stops extending and all the new shoots and foliage have hardened
I was pruning only the shoots whose first new internode was getting too long.
the tree will again start to produce shoots
I usually got 2-3 rounds of growth each season from most branches.
Some things I've noted with all acer palmatums are that the first internode of the season is the shortest
As said, not for me. Some strong Spring shoots had really long internodes.
Thanks 0soyoung!
Summer to Winter 2015
I let the tree grow for the season in its original pot and did some maintenance pruning in the fall, after the leaves fell off. No pests, fungus or other issue.
The winter was not particularly cold, if I remember well, but for sure there were periods with freezing temperatures (in the range of -5C) for many days. The tree was outside on a balcony where I could position it out of the rain if I wanted. I did not protect the roots in any way. I was lucky this time.

To be continued...
Winter to Spring 2016
Winter was cold but the tree emerged from it unscathed. I didn't take any special precautions as the tree sat on my balcony the whole time.
The buds always looked fine through the winter and I repotted it as soon as they started swelling.
To be continued...
Late Spring 2016
First error that I will not repeat. In mid April I pinched some strong shoots (left only a pair of leaves) that I thought were about to elongate too much if I left them grow, right when they were growing. I think this unnecessarily weakens a sensitive cultivar as the Deshojo. Even if I removed only a few of them, I don't think this should be done. Better to let them grow, harden off and prune later on in the season.
I didn't notice any particular bleeding from the cut points though. Maybe there was but is not so noticeable.

To be continued...
Late Spring to Summer 2016
In mid May I pruned the rest of the wild growth. Maybe this is a good time, maybe it's better to wait even more.

At the beginning of July the second growth started and after a few days the new leaves were all wilted. Only the new growth though.

The conclusion after a brief discussion with some of you guys on this thread, was that I might have over-fertilized it. The newer growth is much more sensitive to that than the hardened leaves. Conclusion: fertilize with moderation (at least this cultivar).
Something I read and find very plausible to avoid salt accumulation in the soil is:
  1. water until it starts coming out of the drainage holes;
  2. wait a bit to dissolve the salts already in the soil;
  3. water again and let some water exit so that the salts are flushed away.
To be continued...

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