If you took care to minimize root disturbance, you could probably pot up now with minimal distress to the plant. However, the plant is now preparing for winter and storing energy in roots and cambium for its upcoming rest and subsequent spring growth push. For that reason, I would wait until spring to change containers. The best time is before budswell. Read on for other info regarding over-wintering. Your tree will fare poorly indoors over winter. In addition to the fact your plant will react poorly to indoor cultural conditions, your tree needs a dormant rest period and some chilling temperatures to insure it grows with good vitality in the coming (next) growth cycle. Temperate trees that are deprived of dormancy and the requisite chill that releases them from dormancy either exhibit very weak growth or enter dormancy at extremely unusual times, sometimes in the middle of summer or even during normal peak growth periods. This is usually fatal for the tree. The best place to overwinter your tree is in the ground. Leave it in its present container and bury the container to the rim next to a building foundation, preferably on the north side out of sun and wind. You can also overwinter in an unheated garage, but if you do, the tree will break bud too early. When this occurs, you'll need to move the tree outdoors whenever temperatures are above freezing and back inside when temperatures get near the freezing mark. Allowing the tree to grow in the garage with inadequate light will drain energy and destroy the appearance of the tree unless you prune the weak growth off when you move the tree outdoors, but this is a huge waste of the tree's energy reserves. Al

If you intend to keep the maple in a container, the most important consideration is to protect the roots from severe cold. The small volume of soil in a container will freeze much more deeply than the ground and roots are generally less cold hardy than the wood. If it's possible to store the plant in a cool basement after leaf fall but before severe cold, this would be best. I think survival would be pretty doubtful in an unheated shed. Crimson Queen is quite hardy but Z4/5 doesn't seem realistic for outdoor planting, especially for a young specimen. Leaf filled protective structures can work, but unless the leaves remain dry they will lose their insulation value and invite fungal infection.

Ha no problem qwade and good luck with your endeavor. I've been trying to get to the arboretum all summer (after it was recommended so highly by folks here and I then checked out the website, yowsa!) and will now have to settle for fall; the little ones kept me too busy. I did recently get my mom to agree to come with me and we have a rough goal of next week or the following. Isn't it a shame that more of us aren't in coupledoms where BOTH partners share the obsession?? It works both ways though-- I suppose I could try harder to develop a taste for football, auto mechanics or America's Got Talent but if you try harder, it's not much of an obsession now is it... For today, I am grateful that hubbie does all the heavy digging and lifting when I ask him to. He does enjoy planting and nursing grass seed in our bare patches, so I think there might be some hope for him yet. Time will tell... I giggled about "quicker ways" to kill these little maples. Picturing someone really attacking the poor things, furiously hacking at them or setting them on fire. I do see what Ken is saying as it seems that the colder-than-here pacific northwest is where so many of these mail order trees come from so I don't understand why we'd have problems here but your mention of the freeze/thaw seems a likely candidate. And we did have several days here last winter that were below 10degrees, I think a couple even below zero. Harford County is usually several degrees colder than Baltimore, sometimes as much as 10. And I second the ice damage- perhaps that was a bigger culprit to the deaths of the trees I heard about. I didn't personally lose any other than my little maple but my HUGE pine tree (of some sort, I def do not know my evergreens yet) lost like 8 major limbs! It looks so sad now, big ol' holes. Anyway, thanks for the info on the dormancy/no photosynthesis/no light needed. Boy does that seem obvious now. Think if I do need to move them, into the garage they will go. Then I won't have to worry about the sunroom getting to 42degrees (or whatever, hehe). Here's a pic of one of our huge evergreens. I didn't take it for this post--already had it in my folder-- so you can't see the entire tree.. and it isn't the one with the holes anyway. But there it is nonetheless. Maybe someone here knows what it is? I'm going to see now if you have any pics posted of your bonsai. That's much more than I can imagine taking on at this point in my life but I do always love to look at others'...

In western Washington, Bloodgoods (true Bloodgoods, that is) can get quite large for a Japanese maple. I've seen them at 25+ feet. But that takes decades and they won't grow that big in a container. Even so, a Bloodgood of any reasonable size would be a bear to repot and root prune. IMO, not at all the best choice for a container. Especially if this is your first attempt at growing trees in a container. Truly, you want to start with something smaller. btw, NO Japanese maple gets "freakishly tall and huge" :-) They are usually considered to be small to mid-sized trees.