I actually looked at your 'Diane' when I was trying to figure out where to place this one. I thought it was a lovely photo.
Mine is descended from an older and much too large a plant to be Diane. It must be one of the long-lost heirloom types because I can find no real info on it. I did page through a long list of Hibiscus syriacus cultivars, and found one that's probably it, but I can't corroborate the information. So....it's probably going to remain "Great-Gram's White".
