how do i get rid of aphids and black spot on my rugosas?

Answer 1

lUse an old spray bottle 1/3 dish washing liquid the rest water, spray all of the plant including the bottom of the leaves, this will kill the aphids. As for the black spot , remove all spotted leaves and get rid of them to prevent more problems.

Answer 2

ants are the real cause.ants make the aphids work for them and the aphids are killing your plants or plant.try boric acid in powder form pour it along the most heavy stalks