Question
I have several double knock out roses planted at a commercial site.  Just this week several of the plants are showing leaves with pink and white coloring.  It looks like it could be rose mosaic  virus.  The plants have been in the site for four years with no such leaf coloring.  All I've read about rose mosaic virus is that it is yellow not white and pink.  Any guess as to what it may be?

Answer
Mosaiac virus does show up in other ways than a splattered yellow colouring, but never in my knowledge, in a different colour. As I can't see the plants, I am assuming that the coloration is in the leaves. If it is, then it is coming from the sap in the plant which has somehow got a problem in it such as too much of a chemical. The chemical can be in the soil or it can be in a fertilizer. It can also be in a spray that another person has used and the wind drift has settle on the rose leaves. If you think it is mosaic, I can get information for you from the top man who specializes in rose mosaics.