We use Finale for everything but true grasses. it will burn the roses if you
hit the canes directly, but if careful, you can use it quite close to the
plant. It's a contact herbicide, and won't kill underground storage organs,
such as nutsedge corms. For true grasses, we use Ornamec, which is sold in
consumer quantities as Grass-B-Gone. The active ingredient is
fluazifop-p-butyl. It can be sprayed on rose canes without damage. It's slow,
but does kill the grass completely, even Bermudagrass.