Quite a good pairing in that they flower together but are in contrast in most other aspects. Neither of them are too vigorous – Clematis alpina will never swallow the tree as Clematis montana might and the Morello cherry is unlikely to shade out the Clematis – so in this sense one is not bothered by the other and a peaceful existence lived out. This is how you get a garden, by putting one character with another.
Tend&Grow 