What are you using as soil? That maple is kicking buttEnd of year... cut back some roots under the grow box, hard pruned the top, added wire to intended leader and new left branch. Needs another year or two to grow out after this before its next repot. Plenty of room. I also am using this box.for some other seedlings and such so there are a couple oaks and some red maples dotting the landscape that will be removed at next repot.
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