How to prune mint

Knowing how to prune mint is essential if you want this delicious and versatile herb to be as productive and as healthy a plant as possible. Loved for the scent and flavor of its aromatic oil, mint can be used for all sorts of things, from infusing in tea and for flavoring food, both sweet and savoury, to herbal remedies and for adding scent to flower posies, plus it’s very easy to grow mint and pollinators love it, too.

Below, you can find out from gardening experts why it is important to prune mint, and when and how to do it in order to make the most of your plant.

Why should you prune mint?

It is important to prune mint in order to prevent it from flowering and to promote a regular supply of fresh, young, tasty leaves. For culinary purposes mint leaves are best picked young and will go tough once the plant goes to flower.

‘Younger leaves are more flavorful than older leaves. Once mint has been let to go to flower, the plant ceases production of the volatile oils that flavors the herb, and it begins to concentrate on producing seeds instead,’ explains Allison Vallin Kostovick, organic gardener and blogger at finchandfolly.com.

Left unpruned mint can also go leggy, so chopping it back will keep it looking neat and bushy as well as fresh and tasty.

How do you trim mint so it keeps growing?

Pruning mint regularly will promote fresh leafy growth and keep you in good supply; generally it is best to prune the plant by no more than a third explains as Ashley Irene of Heirloom Potager – designer and creator of edible gardens.

‘Prune mint above a leaf node to encourage new stems. A good rule of thumb is to never prune more than a third of the plant to limit stress. Once mint is well established, pruning weekly is encouraged to keep the plant tidy and productive,' she continues.

When picking aromatic herbs it is important to do so carefully to prevent releasing the essential oils before you need them adds Stuart Thomas of Primrose.

'Prune and trim your mint often to keep getting fresh new leaves. Try not to crush the leaves when you take them off the plant – while it smells great, it's better to preserve the juices and oils inside the leaves until you need them.'

Once picked mint leaves can be used straight away or can be frozen or dried for later use. 

When should mint be cut back?

In summer, when mint goes to flower and sets seed it becomes straggly and the leaves become coarse and lose flavor. When this happens it is best to cut the plant right back to the ground to encourage new growth and a fresh flush of leaves.

Mint has invasive roots which spread easily, so it’s important to monitor growth to prevent it from taking over a border. If you are thinking of growing mint it is recommended to grow it in a container. Alternatively, if you are planning to grow it in a border, try planting it in a pot and sinking the pot into the soil to help contain the vigorous growth. 

‘In the garden, the best way to plant mint is in its own container. In optimal growing conditions, varieties in the mint family can quickly become invasive, taking over in-ground and raised beds,’ says Ashley Irene of Heirloom Potager.