Mint Plants
(Image credit: Chinnakrit)

While there are a number of uses for mint plants, invasive varieties, of which there are many, can quickly take over the garden. This is why controlling mint is vital; otherwise, you may be left scratching your head and wondering how to kill mint plants without going crazy in the process.

Controlling Mint Plants

Even with the less aggressive varieties, controlling mint in the garden is important. Other than placing barriers deep in the ground to prevent their runners from spreading, growing mint in containers is probably the best way to keep these plants under control.

Plant mint plants in bottomless containers that are sunk deep into the ground, or grow them in large containers above ground. When sinking them into the ground, try to keep the container's rim at least an inch (2.5 cm.) or so above the soil. This should help keep the plant from spilling out into the rest of the garden.

How to Kill Mint Plants

Even under the best of situations, mint can become uncontrollable, wreaking havoc in the garden and driving gardeners to the edge. No garden lover enjoys killing plants, even mint. Invasive plants, however, oftentimes make this task a necessary evil. While it's difficult to kill mint, it is possible, but keep in mind that "patience is a virtue."

Of course, digging up plants (and even giving them away) is always an option, BUT even when digging, if just one piece of the plant is left behind, it can oftentimes root itself and the whole process starts again. So if you choose this route, be sure to check and recheck the area for any remaining runners or plant debris that may have been missed.

There are several ways to kill mint without the use of harmful chemicals, which should always be a last resort. Many people have had luck using boiling water to kill mint. Others swear by using a homemade mixture of salt, dish soap and white vinegar (2 cups salt, 1 teaspoon soap, 1 gallon vinegar). Both methods will require frequent applications onto the mint over some time in order to kill it. Be aware that these methods will kill any vegetation that it comes in contact with.

If you still have problems, try covering the mint with thick layers of newspaper, followed by a layer of mulch to smother it. Those plants that still manage to find a way through can usually be pulled up easily.

When all else fails, you can grab the herbicide. If you don't feel comfortable using chemicals to kill mint, your only option may be to get a good shovel and dig it all up. Be sure to get under the plant's main root system, then bag it up and dispose of it or relocate the mint in a suitable container.

Mint is well known for getting out of hand in the garden. Controlling mint through container gardening often helps; however, you may have to consider other tactics to kill mint if this plant becomes unruly.

Note: Any recommendations pertaining to the use of chemicals are for informational purposes only. Chemical control should only be used as a last resort, as organic approaches are safer and more environmentally friendly.

Nikki Tilley
Senior Editor

Nikki Tilley has been gardening for nearly three decades. The former Senior Editor and Archivist of Gardening Know How, Nikki has also authored six gardening books.