White powder on roses
One of my rose bushes has a white powdery substance on its leaves. I am guessing its some kind of fungus. What should I use to get rid of it? Also their are other rose bushes around this diseased one. Should I also treat these to prevent a similar outbreak? I think I remember reading about some home remedy for it, perhaps baking soda solution or something. Tell me if I am correct and what concentration I should use. I would really prefer using a home remedy rather than buying expensive store chemicals or antifungals.
Thanks for your help.