(I'm in Zone 4)
About 20 years ago, I put in about 8 different clematis, different varieties, on the W and E and S sides of the deck. The ones (4) that did the best are the W and E ones. They seem to like having their feet shaded and sun for part of the day. Mine still flower and I haven't pruned them at all (maybe I should). The woody stems still sprout each spring and they don't seem to need any special care, like they did (watering) the first year, to get established. The ones that didn't make it had to compete with BitterSweet vines and another set with large evergreen bushes.
QuickSilver, nice article, thanks. ~Bliss