Is this a disease or are bugs attacking my flowers? We do have some Japanese beetles around lately. Could this be the problem? What can I do?
Knockout Roses Have Holes in Leaves
Give the rosebushes a treatment of Bayer Tree & Shrub granules. The granules feed the rosebush to increase vigor and also release a systemic insecticide that moves up through the root system and throughout the rosebush. In this way the insects making the holes, likely a long snout beetle, are controlled.