I decided to go with Huldine (white) and another blue.
Need the contrast to be great so pls suggest the 2nd one. I am leaning toward Clematis "Rhapsody"...is it a good pick?

I think Rhapsody is my hands-down favorite color of all the clems I grow. I've only had it for a couple of years, so it's never bloomed that much so far, but that rich, deep blue is a real stunner! Mine is planted under a crabapple tree, so it doesn't get a lot of sun. I think I have read that it would fade in full sun. Come to think of it, it's paired with Huldine on that crabapple. Huldine is years older than Rhapsody, of course, so perhaps Rhapsody will catch up, but for right now, Huldine reaches to the top of the crabapple, and Rhapsody is much shorter, like 4' tall. That amazing color, though!

Thanks!

How is Henryi compared to Huldine?

If I chose Will Goodwin (lavender-blue clematis) to pair up with any of the 2 above whites would it be good?Will Goodwin is the best true blue right?

Can I put 2 clems in same pot, if so what size pot?
--Thanks, Kris(se PA)

I've had mixed luck with Henryi. I bought and lost at least 2 before I got my present one, and this one is REALLY hardy! So hardy, in fact, that it killed the small crabapple I planted it on. Huldine is more graceful, I think, with smaller flowers that are not quite as white and blocky. Huldine has light pink/purple ribs on the underside of the flowers which add interest if you're seeing it from below. I think Huldine grows taller, at least at my house.
I think my Will Goodwin died, and I don't grow any in pots, so I can't help you there.