I have roses and columbine in flower beds with rocks. The grass is invading the entire bed. Would like to leave the rocks, but thwart the growth of this very invasive grass. I don't want to kill the flowers. Thank you. J. Camp
Grass (Duck Grass) in Flower Beds
Certified GKH Gardening Expert
Are you referring to crab grass?
The only save way to remove weeds from your flower beds is to hand pull.
Using mulch will help keep weeds down.
Here are some links with more information.