Rose Leaves Yellowing

Question

I have white roses on either side of garden, and the leaves of both have started yellowing. One stem at a time, all the leaves turn yellow. I use rose fertilizer, plus slow-release (been darn hot lately). One rose is 30 years old, the other is a cutting of it, and produces beautiful white flowers. I do not want to lose them.

Answer 1

This article will help you:
https://www.gardeningknowhow.com/ornamental/flowers/roses/yellow-rose-leaves.htm