Okay...Clematis lovers! Put on your thinking caps for me.

I would like to get lots of suggestions of a clematis to put with 2 orange/yellow roses and a red castor bean. I was originally going to put "Blue Light" there but am now unsure. I may still get that one but I'd like more ideas. I would like something in the blue range; something that will not be lost.

This area gets full sun between 10am and 5pm. Sometimes hot, blistering sun of 100º. It will get plenty of water and, on occasion, but not too often, lots of water. No standing water, though.

Westerland and Betty Boop are the roses and Carmencita is the castor bean.

You issue may be the time it takes for a newly planted clematis to establish vs the castor beans huge seasonal growth.
Try and find the biggest plants you can, or order several of the same type from silverstarvinery.com

plant the clems on the outside of the roses so you can easily get to the clem and attend to it without scratching yourself up in the process. as i mention this i can see my right forearm which is all scratched up from rose and clem harmony.

You might want to consider a betty corning vitacella, very vigorous. light blue to lavendar bell shaped flowers. "Clematis on the Web" is your best online info source. Maybe lower growing Clematis Durandi for a deeper blue, to fill in the bottom.
you could get 2 betty corning and 2 durandi and place one on each side. also consider perele de azur, a very popular internationally known clem.

as with any perennial grouping multiple plants gives a better display and balance to the design.

I am no pro on this....however why not go with a group 3 but a darker purple? Too dark maybe? I am thinking Etoile Violette....or going to the other extreme and go with white? Maybe John Huxtable? I am only suggesting those 2 cause I already have them and they do well for me so far! And you can cut them down in the spring!

White may also be a nice contrast. Pistachio or Ms. Bateman maybe?

Thanks for the suggestions. Are they Z5?

I can't wait to do all the new beds.