I noticed within two weeks of spotting aphids last year lady bugs showed up and had a feast. I didn't see hardly any leaf damage. The other fall back for me is spraying them off the plant with the hose. They have a hard time getting back on the plant once you do this and sometimes it is enough. I would check to see if you see any ladybugs on the rose. I only saw 2 lady bugs but they took care of all the aphids.