I'm looking for a late summer/autumn clematis that will cover a trellis in one season. I had a sweet autumn clematis at my old house that was a rampant climber and I loved it because of its small flowers and vigorous growth. Several people have now told me that it is considered an invasive plant where they live and it also self-seeds. I live in the Pacific NW and although it was a rampant climber, I didn't consider it invasive and it didn't self-seed. Is there another clematis that is somewhat comparable?
It's not at all uncommon for things that are invasive in one area of the country to be perfectly fine to grow in other areas of the country. So before you decide not to plant it, I'd do a little searching and see if it's considered invasive in WA or not--quite possibly it's not and then you could go ahead and plant it.