Jeff Gillman, hort. prof. at U of MN & frequent contributor to Fine Gardening, recommends staying away from tobacco based insecticides. Not because they don't work against insects but because tobacco has a couple of fatal viruses that infect some of our garden plants, especially geraniums, potatoes, tomatoes, peppers, etc. Roses aren't on this list but because you probably grow some of the above listed plants, it is very easy to contaminate equipment & your own hands with these viruses & transfer them thru out your garden.

Since roses are thirsty by nature you may have to remove the soil and replace it with new sterile potting mix.
And sterlize the container...

Some people use yellow sticky tape to catch the adults...

This post was edited by jim1961 on Fri, Sep 27, 13 at 13:12

Does anyone know if coffee grounds work? Jerry Baker wrote about emptying the pencil sharpener into the potting mix to add fine cedar shavings to keep bugs away.

This guy has an interesting approach...lol

Here is a link that might be useful: Getting rid of fungus gnats