Pulling best way to ban pervasive mint

I have an herb bed that is being overrun by mint. What was one small plant now occupies a third of the bed. My husband has threatened to kill it with an herbicide; I want to beat it back without harming the butterfly bush, azaleas and herbs it has surrounded. Can this be done?

Mint is adept at spreading via long rhizomes that lie just under the soil surface. It might even find its way around or under obstacles such as bricks placed in its path. It is best in a pot.

There are no herbicides that are selective for mint. Your only option is to treat the portions of the plant that you can with a nonselective herbicide, such as Roundup. With luck, the herbicide will be drawn down to the mint’s root system without harming the desired plants. You might need to combine hand weeding with herbicide treatment to eradicate the mint. Fortunately, the rhizomes tend to be just under the soil surface, so you won’t need to dig deep to get rid of them.

Scott Aker is a horticulturist at the U.S. National Arboretum