There's only one yellow variegated Caryopteris that I know of: 'C 'Summer Sorbet'. It does not lose its variegation, is stunning in bloom, and provides good presence when not in bloom. Requires well drained soil and full sun. That's about it.

Spazzycat - you are right about there being only one yellow variegated Caryopteris. I thought Worcester Gold was variegated as well, but it is solid gold leaved. I guess that makes the selection process easy... LOL BTW, I loved the pictures of your Sunshine Blue and your entire garden. Great composition!

I shovel pruned Worcester Gold and replaced with Sunshine Blue and I have Summer Sorbet as well. Both are superior and smaller than Worcester Gold.

WG grew to almost 5' wide and faded badly for me.

Summer Sorbet is under 3' and the variegation has not faded.

Sunshine Blue is under 3' and has not faded to green.

They were both planted from gallons last summer so aren't mature yet but I'm very happy.