They say that fully healthy roses cannot be harmed by aphid infestations, and that may be true. However, we do not live in an ideal world, and it makes no sense to go out on strike until it appears.
We have abundant Rose Aphids this spring, but haven't seen them for the past few years.
We mix liquid dish soap at the rate of 1 tbsp/gallon in spray bottles, and spray the roses, especially their succulent tips, with it. Dead aphids by the thousands, without poisoning anything else. The surfactant suffocates the buggers. I brush off any Ladybugs first.
Mrs. BD claims that she is waterboarding them to death.
One treatment ought to do it. Best done before the first bloom. Had to do it today.