I don’t really get rust on my roses, but I would strip off the heavily infected leaves. You could try washing the leaves with soap solution, but I don’t know if that will save them. The rose will grow new leaves eventually, so I think it’s better to get rid of as much fungus as you can. Then I would spray what’s left with fungicide, both tops and undersides of leaves, and all over the stems. I try to stick to organic stuff first - like Organocide. It’s an oil spray that it more preventative against fungus, but helps to control it if already there. It also kills insects by smothering, but is supposed the be bee safe once the spray dries. If the fungus is really bad, I use Daconil fungicide. Not bee safe, so I try to avoid getting it on blooms. It does leave white residue on the leaves, so it’s not pretty once done, but if you need to save the plant, use it.

Next time, as soon as that particular rose leafs out, try spraying it with a preventative to help ward off the fungus before it shows up.

Also, some roses are water-hogs and need more frequent waterings in order to be healthy. I don’t know if Easy Does It is one of them, but it could be worth a try.

You can also try watering the plant with dissolved aspirin. It’s supposed to kick start/boost the plant’s self defence system.

MAD, thank you very much for such detailed information! I am saving it for future reference.

I removed as many infected leaves as I could. But I found new infected leaves every time I went to check it. Easy Does It is very vigorous to put out lots of new leaves, but at the same time many leaves are becoming infected and drop out. It's like an endless battle........

I will try all the methods you mentioned. Hope I can save it. It has given me some perfect blooms. I don't want to shovel prune it unless I have to.