This clematis is hardy to zone 4 and blooms from May to June, with a second burst of bloom from August to September. I have it in a pretty large pot (about 22" in diameter) and have some low growing plants around it (see last week's post on Erodium). It likes a sunny location and good drainage. I'll have to study up on the pruning guidelines to ensure I get good growth next year.
Give climbers a try, especially if you're really short on space. If you can't plant out, then plant up.
Bookshelf: Container Gardening Books