I went out to look at the buds opening on my Jackmanii and saw a bunch of them deformed and shriveled looking.
It's only affecting the flowers, so I don't think it's Clematis wilt. What could it be?
Thanks in advance!

Suggest question be moved to the Clematis forum

I moved it back to the AAQ forum, more members here than the Clematis forum and maybe someone would have an idea.
It looks like some have chew marks, could be insect damage.

Thanks Sue!
It's almost like powdery mildew. The climbing Peace rose it's on has mosaic disease, it turns the rose leaves yellow striped. I wonder that could play a part in it?
Also, I've had problems with my tomatoes the past couple years and the Farm Advisor said it's Beet Leaf Hopper virus. I wonders if it could be how that virus plays out in Clematis? It's not affecting the clematis on the other side of the garden arch.

Thanks again!

See if this matches the description, found on Clematis on the Web site.
http://clematisontheweb.org/ne...

So I took some of the flowers down to the nursery. She is very knowledgeable. She said it's not powdery mildew, because it's not powdery. *sigh.
She recommended I talk to the Farm Advisor. He was out so I have the number for UC Master Gardeners.
Still on the hunt for the culprit that is destroying my Jackmanii