Evison is listed as the hybridizer at the top of the databox: "Raised by Raymond Evison & Poulsen."
Clematis Bourbon™
It's going to look great scrambling up that plum tree. Mine was supposed to climb a red twig dogwood, but it climbed through the latticework on my fence while I wasn't looking, and now most of the blooms are on my neighbor's side of the fence.
I'll have to be more vigilant about keeping it in line next year.
