We have a large area (6 feet by 6 feet) of mint plants in our yard that need to be killed. The previous owners of our new house said the area of mint has been there for years and they tried to kill the plants too. I am willing to use anything.
Killing Mint Plants
Certified GKH Gardening Expert
Round-up or boiling water will kill it, but they will both also kill anything else they come in contact with. You can also try covering the area with a scrap piece of carpet for a few months. This article will also help: