10 months, 3 weeks ago Do these knockouts have a virus? Knockout virus? Q&A Can you tell from this picture if the knockout rose had the Rosetta Virus? - Marilyn - Comments Dennis Patton 10 months, 3 weeks ago Unfortunately this does appear to be rose rosette. The only control is removal. The good news is you can replant in a month or so once the old roots have died. If you would like another opinion bring a sample to your local Extension office. Dennis Johnson County Extension Sign in with Facebook to comment. Copyright 2014 The Kansas City Star. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.