Oh thanks so much, that's very encouraging! Especially the part about the roots. Keeping them moist, I can do.
Maybe I'll even do it this week. August here has been cooler than usual, and it's more than half over. I can shade the rose. I hate to cut it back too far though because all of the healthy leaf growth is way up top, leaning for what sun it can find, poor thing.
And more roses may indeed join it over there. We do have lots of room for lots of things!