| You would have to remove all of the soil in the area, not just the roses. It could also be imported in with any potted plants that you might bring in. Other than insecticides, a few people have tried mulching heavily around the plants with newspaper as a barrier method. The link below has more information. Good luck. |
Here is a link that might be useful: I'v Had It!-Spraying Pesticides for Rose Midge