That last post left me scratching my head... "I'd not worry overly about manure or potting medium (after a year, both of these are a non-issue)..." Not sure what was meant there. The issues actually get worse (particularly drainage) as the potting medium breaks down. That's one of the biggest issues that has to be dealt with when growing long-term in containers. "They are still small enough to make the adjustment without worry or excessive transplant shock." I don't understand this statement either. Small cuttings, possibly lacking good root structure, are actually more likely to suffer from transplant shock than larger, well established plants. "Well-drained, slightly acidic and organic soil..." That would be great if that's what's there, but don't fill a planting hole with that stuff in the middle of a bunch of whatever the native soil is!

Was it grafted, and did the break occur above or below the graft, if it was grafted? If below the graft, get another tree, as what sprouts won't be the tree you bought, but another maple. If it was own-root (unlikely, unless it was an un-named seedling, as JM cuttings don't root well), or the break came above the graft, then the chances are good that it will recover and leaf out fine come spring. I would give it a little extra time to leaf out in the spring, before deciding it is truly gone. You MAY have to to some training/pruning to get a nice shape to it as it grows, and you may get a nicely shaped tree all on its own. Putting a low fence around it for a few years should stop a recurrence in the future, until it's big enough to be safe.

Gardengal, Thanks for the comparison to grafted plants pots and the reminder about bark based compost. It almost sounds like I could leave the plants in the 4"x9" they are in now for another year. That would be nice. Re: "Varieties" I sort of didn't think about seeds not being 100% true to the parent plant, and I would not call them the original. But having said that it's hard NOT to call these guys 'varieties'. There is an obvious difference between the little guys that resemble the parent pretty well. I have 6 little red ones from a Sherwood Flame that look identical to one another, 6 pinkish-green Japanese maple trees from a Sango Kaku, and 1 from a Seiryu... . So yeah they are not official but hey you can't beat the price----and they are absolutely beautiful! Maybe I'll give them each a unique name, like Bardamu's Rufescent Sprout, etc then sell them on eBay. There are so many varieties, and I sure can't tell what's what in this crazy world. Ken, I'm not any more worried about these plants living through this winter than with my other potted plants--which is a substantial concern. But here I didn't bring it up. I just wanted to know an acceptable pot size for a 2 year old JM tree for next spring. I live in Southern Massachusetts in a spot I like to call z6. I really should put that in my nickname. Since the generic acer palmata are in a small pot now, I am burying the pots in ground under a wind shelter, so I think I've got that part covered---or I am in for an unpleasant surprise!

Stephen, I can only report what I do :-) Although our climates are pretty similar, I'm sure we get somewhat hotter in summer and that is also our dry period as well.....often extremely dry. 1) You have already come to realize that a durable and very barky potting mix is best. Ideally, the best time to repot or up-pot is in late winter when the tree is fully dormant. And this timing is rather critical if any root pruning is required. But if I am just potting up from a nursery container to one of my own in a larger size, I do it whenever ;-) 2) Your planting techniques sound fine. I don't pack the soil in too tightly but I do firm it in place. If not firm in the container, it can compact and the tree can sink. 3) I only water around once every 5 days or so unless the weather is very hot and dry. Then I move that up to every third day, sometimes every second day but only if we are having extreme weather. And most of my containers are quite large, so that reduces the need to water more often. I water until the water flows freely out the drainage holes. 4) I use the Osmocote (but any controlled release fertilizer will work) when I pot the trees up initially and again at the beginning of each season. I also provide some dilute liquid fertilizer every now and again as it has lots of the trace elements Osmocote and other ferts lack. I don't think it makes much difference what exact product you use other than to avoid any dry organics - they are just not very efficient with any kind of container soil. Liquids or water soluble ferts are the easiest to mix and use but will need to be applied a lot more often than the CRFs. Finally, your little tree with the spotted leaves is not exactly in bad health. It may just need a bit more TLC and to approach its care with more consistency with regards to watering. I can say I have been quite brutal with mine at times when my life gets too busy but they all spring back well from any temporary mistreatment. Growing JM's in containers to their optimum potential takes a dedication that I am not always able to provide but most seem thrive in spite of it :-) Right now I have one that should have been potted up a couple of seasons ago - it is in too small a container for its size and I am sure it is rootbound as it is putting out really no new growth but otherwise leafed out well. I just water it a bit more frequently to make up for all the roots filling the container and it is at the top of my list for root pruning and transplanting this winter!