I think Porkpal's suggestion is pretty good. I've had several roses disappear underground for the better part of a year, then come back fighting. It doesn't happen often, but it does happen. Ones that come back, tend to be well established when they do. If you love the rose, it can be worth waiting for a whole year. I frequently lose patience first, and clear a rose out to make room for something else when it looks like it might possibly be dead.
