How to Grow Mint Without Letting It Take Over

Most herbs, such as thyme and sage, form a clump and stay where you put them. Mint spreads by rhizomes, which are underground stems that travel sideways and send up new shoots. The Royal Horticultural Society notes that most mints are vigorous, spreading plants that are best grown in pots to keep them contained.

That is why mint planted in a bed so often ends up elsewhere. It is the plant's normal growth habit, not poor luck or soil.

Grow mint in a container. It can be a freestanding pot, or a pot sunk into the ground. If you sink a pot, keep its rim above the soil line so runners cannot arch over the edge and root in the bed.

It is possible, but you will need to manage it.

• Directly in an open bed: high risk. Once established, removing every runner can take a long time.
• A freestanding pot: the safest option.
• A pot sunk into the ground: gives an in-ground look with containment, if the rim stays above the soil.
• A raised bed: still risky unless the mint is in its own pot inside it, because the edges of a bed do not reliably stop rhizomes.

Picking Your Mint

Peppermint has a stronger menthol flavor and suits teas. Spearmint is milder and sweeter, and is the usual choice for cooking. Other mints, such as chocolate or pineapple mint, spread in the same way, so the same container rules apply.

Planting in a Container

Use a pot with drainage holes, large enough to hold the plant with some room to grow, and a container potting mix. Loosen the roots gently before planting, set the plant at its original depth, and water well afterward.

Placement and Light

The Royal Horticultural Society says mint is happy in full sun or partial shade. In hot climates, some afternoon shade helps the pot from drying out and stressing the plant.

How Often Should I Water Mint?

Keep the potting mix evenly moist. The RHS advises checking potted mint regularly during the growing season, especially in hot, dry weather. Check the soil with a finger, water until it drains when the top feels dry, and wait if it is still damp.

A Simple Pruning Rhythm

Regular harvesting keeps mint bushy and compact. Pinching back the growing tips encourages branching and can delay flowering, after which leaf flavor often declines. The RHS suggests cutting the whole plant down to about 5 cm (2 in) from the base after flowering, to encourage fresh growth.

Harvesting as You Go

Snip stems just above a pair of leaves whenever you cook or make tea. That keeps the plant compact without separate maintenance.

Repot or divide potted mint every few years, depending on the size of the pot, so it does not become overcrowded.

• Tea. A few fresh leaves steeped in hot water make a simple, fragrant cup.
• Infused water. Bruise a few leaves and add them to a pitcher of water.
• Salads. Torn mint brightens fruit and green salads.
• Sauces and chutneys. Mint sauce and chutney both use fresh leaves.
• Desserts and drinks. Chopped mint works in fruit desserts, and muddled mint is the base of drinks such as mojitos, or a non-alcoholic version.
• Southeast Asian dishes. Fresh mint is a common herb in noodle salads and wraps.

Cut mint does not keep especially well, so harvest what you plan to use within a day or two.

Mint is easy to propagate. The RHS lists three methods: dividing an established clump, taking softwood cuttings in spring, or rooting cuttings in a jar of water and then potting them up.

Every rooted cutting has the same spreading habit as its parent, so give each one its own pot, not a spot in an existing bed.

• Leggy, sparse growth: usually not enough light or not enough pruning. Move it somewhere brighter and cut it back.
• Dusty or powdery spots on leaves: the RHS names mint rust as the main fungal problem. Improve airflow, avoid wetting leaves, and remove affected leaves.
• Runners escaping the rim: trim them at the base where they cross the edge, before they root.
• Wilting despite moist soil: roots may have filled the pot. Repot or divide the plant.

• Royal Horticultural Society, "How to grow mint"