In your zone (BRRR!) you'd have to be very careful about wintering grasses in pots. Prairie Dropseed is hardy to zone 3, but traditional thought indicates you lose at least 2 zones in unprotected containers. That means you'd have to bury a pot of it, but doesn't mean it would survive. The grass, in situ, will drop roots much further into the ground than a pot will allow. This will enable it to survive the cold of winter much better than even a buried pot. Same with Junegrass. Hardy to Z3, and an unprotected pot will be the equivalent of Z5. Bury it, and you might buy a zone, but you also might not.

Brrrr - you got that right! Thanks for the advice. I kind of knew that, but I didn't want to believe it. We are moving next year and I just didn't want to dig it all up - I am feeling kind of lazy. Oh well, if I want it, I'd better plant it!