East of the Rockies? Check your nearby Knockouts
As massed plantings of Knockout roses beautify the landscape, the planters of masses of Knockouts too often plant them and then come back once or twice a year to prune them.
In some areas, these plantings can be a reservoir for Rose Rosette Disease.
For your own roses, you are going to need to keeep an eye out on the uncared for roses in your neighborhood to see if they remain healthy.
Today, I was out photographing Knockouts for a talk next weekend in Asheville NC (Arboreteum 10 am Saturday) and one planting that had looked ok a month ago now has two of seven KOs sick with RRD. Another planting had one of eight sick and across the road from it seven of seven sick. The latter two beds were at most two tenths of a mile from both Home Depot and Lowes where more Knockouts were being sold.
RRD on Knockouts stands out as different from normal good KO blooms, buds and leaves. It is a danger to roses down wind.
Take some time to read my e-book, multiple chapters and it has a FAQ.
Here is a link that might be useful: Rose Rosette E-book