Apple Blossom

Now before you go on to tell me that this is no apple tree you've ever seen, this varietal of spring Clematis is 'Apple Blossom' It is supposed to be evergreen and is the background for my butterfly garden. I am hopong that the fence will provide enough heat to offset the shade it provides. It is west facing and will be in shadow a large part of the day until it manages to crawl up the 54 inch fence. As you can see it has a fair start. I am still hoping to find a winter blooming clematis, but if not then something for the late summer will do and then I won't care if it is evergreen or not as it will grow with this one and bloom at a different time. Any thoughts as to what color the next one should be?