I would suggest Prince Charles, planted with Viola. Prince Charles is a lovely blue/lavender, Viola the deep, velvety purple. Both can be good sized and are very easy to grow when planted properly:
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Lyn, reading your post I'm not sure that you realize that clematis will not cling to a wooden fence. They need something small to cling to. Here's a picture of one of mine in it's first year last year that shows what I've done to my wooden fence so I can have clematis grow on it. Florida Sieboldii was in it's first year in my garden last year. This year I'm hoping it will cover much of the exposed part of the fence.
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" But it also needs to be tough because there is no way I could get a hose out that far. It would be pretty much full sun. I'd like it to grow fast and be huge because there is a lot of fence up there. "
Also, may I interject and say that clematis need to stay moist..so you'll need to water..also, they are the "Sleep", "Creep" and then "Leap" Vine..a good 3 years to get established..so don't expect immediate coverage...Jeanne

You are certainly going to have to drag a hose out there if you are going to grow Clematis successfully. :)

Thanks for the great advice. I did not know that they wouldn't climb a fence. I suppose I was also under the false impression that they would be care free. Its logistically impossible to get a hose up there so I'm glad I posted this before I spent any money. Seems I need to do some investigation on a different vine or give up the idea entirely. I do love clematis...maybe I will grow some around the house where I can actually take care of them. Thanks for the advice!