there are some odd yellow patterns on the leaves of my rose bush.
I don't see any black spots or mildew, and the yellow pattern does not cover all the leaves - only a few.
Yellowing is a sign of stress in rose leaves so there is no simple answer to your question. Read the attached article on rose leaf yellowing. If you don't find an answer that fits your situation, take a small cane or several leaf clusters to your extension service office. The Master Gardeners and extension staff may be able to pinpoint the cause. Find your county's extension office at this website: Extension.Search.org