Hi I’ve inherited many things recently in a garden most of which I don’t know because they are not in bloom now, and I can’t tell from foliage. One of many is this rose bush. The main stem at the bottom I sawed off bc it was dead. But the thinner one is still ok. I scraped back to cambium and it’s still green there. There are only three buds right at the top. All the leaves have disease I think. How best to save this?