You always want to pick a container that has a flared opening - where the top of the container is the widest point. Urn shaped containers - those that narrow in at the top - make it virtually impossible to unpot and root prune/refresh the soil without destroying either the container or the root system of the tree. Therefore, I'd go with the brown container rather than the green.

I tend not to wash all the soil off roots when I am potting up at this time of year as it is particularly stressful to the tree unless done very carefully. And most of the vendors I purchase from tend to use a very barky soil mix anyway, quite similar to the 5-1-1, so much less of a need to remove.

I tend not to use any groundcover type plants with my containerized maples as they just complicate things when it comes time to repot or root prune. But it won't hurt the plant if you do. btw, Red Select is a very low and spreading weeping laceleaf, so groundcovers may not be necessary to dress up the pot - you will barley be able to see them once the tree matures a bit :-))

Have you planned what to do in winter? In your zone, containerized JM's will require winter protection.

Thanks so much. Planning on pulling him inside for the winter,I know I can't handle the cold

Just for clarity's sake, hopefully by inside you don't mean inside your heated living area. JMs still need a period of dormancy, so the inside area you speak of should be an unheated area like a shed or garage or protected porch. It is sometimes beneficial to further insulate the pots with things like thermal tarps, bubble wrap and leaves, mulched inside a larger bin, or other methods to create a thermal break between the pot and the cold.

In the ground, the roots are only exposed to the cold from the top, and mulching and snow cover help to mitigate that. In a pot, they are exposed from all sides, and a little extra help can go a long way.

Gardengal, that is the size of tree that i got at walmart for $15 dollars. They also had red select. The original poster may have gone to wally world too!