Now I know where all the aphids went when I chased them off of my roses by blasting them with the hose. They just regrouped all over my hibiscus--and they brought friends. It looks like there may be scale, mealy bugs, and whitefly there as well. These aren't responding at all to blasts from the hose--doesn't phase them in the least.
I've been considering re-locating the hibiscus anyway, so now may be the time. I think I'll dig it up and pot it and quarantine it for a while until I get the bug problem under control. The climbing rose I just bought will probably do better in that spot anyway.
I guess I'll need to get some kind of insecticidal soap or horticultural oil to use on the hibiscus. Or does anyone out there have a home remedy that really works?