Yes, this photo is of a red and white Dahlia, not a rose. The title "Painting the Roses Red" comes from a line in Alice in Wonderland which the duel color reminded me of. Thank you to everyone who commented and voted.
I'd appreciate rather less light creeping round from the back which burns out the highlights and I'd like to see a sharper focus. The flower doesn't really benefit from the soft focus approach. I'm not even sure that it's a rose - a dahlia perhaps?