We moved into a house that has two large rosebushes. I know very little about roses. They are small, very pale pink blooms. When they are just beginning to bloom, though, many of the blooms get sort of rusty looking and they die. One of the bushes also has caterpillars on it. I hate using poisons in the yard, but I will if that is the only solution to these two problems. Any advice? Thanks in advance!

