Japanese maple repotting: from nursery to trainer

I have grown this Japanese Maple from a seedling and recently got the nerve to repot into a training pot. I am in zone 9, San Jose California. Our evenings are in the 40’s with daytime temps in upper 50’s to low 60’s (this week).

  1. I am afraid I went too hard on the root pruning, if so is there anything I should do other than wait/pray?
  2. should i let the tree acclimate for a year before considering any branch cutting? My biggest concern here is creating a taper and t would like to cut the current leader ASAP.

Thanks in advance for any thoughts.


I think your root pruning looks good. I routinely do that level of pruning on Japanese Maple. I would hold off on the big cut for now. If it grows well this spring (it probably will), I would then do the cut after the new growth hardens. I think you can get aways with the two major actions in one-year if you get good spring growth since you have lots of other branching.


That’s very reassuring. I’ll hold tight and allow for that new growth.

Clarifying question: you recommend waiting for the spring growth to harden before making any big cuts. Do I interpret this as holding off on the single “taper” cut until growth hardens? Or can I go to town on shaping as well?

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I would only make this big cut this early summer after the first flush hardens. if you get another push indicating the tree is strong, then you can probably do additional pruning and shaping in the fall as the leaves come off. Remember the rule of thumb is one major insult to the tree per year. Japanese maples are often strong and can accept more than one, but it is better to be patient and allow the tree to gain strength than to overwork it and kill all or part of it, particularly since you have a nice nebari started and decent sized trunk.

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Marty - many thanks! I’ll be following this advice and watching the tree this coming year.

I’ll be back on this tree for styling advice before I make the first cut.


I think @MartyWeiser is spot on, the root prune looks great and the advice to wait until summer for the large cut too. As far as the cut is concerned I would recommend making the cut about an inch above where you will eventually have the new leader. Leaving that stub allows for branch dieback and the tree to compartmentalize at the collar. You can come back later and clean up the dead nub.

How long have you been growing this one? It looks great!! Happy and healthy for sure.


Appreciate the input Moon. Thank you!

I’m guessing this one was acquired around 2005, give or take a few years. I purchased it as a sapling and planted it right into a tiny bonsai pot with backyard soil.

In fact, that’s how I grew all of the pre-bonsai material I have. All, except for this maple, are olives I grew from seed starting in 1990. I’m terrified of taking next steps on those, but it’s gotta happen sometime, right?

If they are making it now in pots with yard soil you are doing something right for sure. I bet they don’t miss a beat when you take the next step with them.

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So far so good!

Late September update. Tree had a great run in spring and summer. I’d like to make that major cut that I missed in the early summer. Is it a good time for that?

Also, the roots have made it into the ground under the pot (through the drainage holes). Ok to leave as is or should I deal with this now?

Thanks all!

Once the leaves start to go over for autumn you can cut. If you plan to repot in the spring, I would leave the roots well alone until then but if not you can leave them and it will help fatten the tree quicker.