Just keep them watered well but not soppy wet and keep them well fed. The leaves will turn yellow on some of the foliage as they are no longer needed or to help allow more air flow through the bushes in times of high heat. Here is a link to an article I wrote for you as well. Link>> https://www.gardeningknowhow.com/ornamental/flowers/roses/yellow-rose-leaves.htm
Answered on June 20, 2012
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