HELP! For the first time ever my knockouts have a terrible case of rust. My local garden center told me to use a product called BONIDE INFUSE. I was advised to spray Infuse and in a week or so cut them back to get rid of any infected leaves. I am very upset as I have 25 of them lining my driveway. What is the purpose of spraying a chemical to only cut them severly back? I do realize Infuse is a systemic, but, why waste product. What have you done if you have this horrible problem? HELP.
Rust on Knockout Roses
Certified GKH Gardening Expert
This article should be of some help to you: https://www.gardeningknowhow.com/ornamental/flowers/roses/rose-rust-disease.htm
Also, our rose specialist normally recommends treating this issue with Green Cure fungicide, as it is both effective and safe to use (do chemicals to worry about).
Nikki is correct. The article will give you some information and the Green Cure is proven very effective to help with this problem.