Growing Mint Indoors

Mint is an herb from the genus Mentha spp. There are many variations available for this hardy perennial, each with its own unique characteristics. Growing mint indoors keeps this refreshing herb on hand all year round. 


Mint Plant Care: Appearance

Mint is an aggressive grower, reaching a height of between 12 and 18 inches tall (30.4 to 45.7 cm) and 18 to 24 inches wide (45.7 to 61 cm) quite quickly. The stems of Mint plants are square with leaves growing in pairs opposite each other. Planting mint in pots makes it easy to control its size and growing environment. Blooms appear in summer as small, white flowers that attract many pollinators when grown outdoors.

Planting Mint: Sunlight Requirements

Grow Mint in bright, indirect sunlight. Morning light from an East-facing window is ideal. Full sun is acceptable but increased water is needed and the plant will need to be monitored for signs of scorching. Avoid planting Mint, or placing its pot, in full shade as it encourages legginess and reduced flavor.

Mint Plant Care: Watering Your Mint

Keep your Mint plant’s soil slightly moist, but never soggy. Water once the top 1 inch of soil feels dry when a finger is inserted into the soil. Mint will indicate when it needs water by the slight wilting of its leaves. Watering in the morning, especially when moved outdoors, is recommended to keep the plant hydrated during the warmer hours of the day.

Soil and Fertilizer Requirements

Mint plant care requires well-draining soil amended with some organic matter for nutrients. Potting soil with compost and perlite is ideal. Use fertilizer for your Mint plant only if you have not already added compost or other organic matter. Feed your plant once per month, from spring to fall, with an all-purpose, houseplant fertilizer.

Temperature and Humidity

Mint is adaptable to most household conditions. Average temperatures and humidity levels in a home are acceptable. Temperatures around 70 Fahrenheit (21 Celsius) work well with humidity around 40 percent. Supplement low humidity by placing a tray filled with pebbles and water under the pot’s saucer. Peppermint is more cold-hardy than other varieties of Mint, while spearmint tolerates higher heat.

Harvesting Your Mint Plant

The Mint plant is ready for harvesting once several of the stems reach a height of 6 to 8 inches tall (15 to 20 cm). Snip the stems above a cluster of new, smaller leaves. Harvest as needed, but never more than one-third of the entire plant at one time. Regular harvesting encourages new, healthy growth. If the stems begin to grow longer, and the leaves shorter, cut the entire plant’s height back by half to encourage new growth. 

Propagating Mint

Propagate your Mint plant by cuttings in the late spring or early summer. Snip a stem 4 to 6 inches (10 to 15 cm) long and remove the bottom leaves from the stem. Fill a small pot with potting soil and perlite and plant the cutting. Place the pot in bright, indirect sunlight and keep the soil moist. After two weeks, pull lightly on the stem to test for root establishment. Resistance indicates a healthy root system. Care for the plant as a mature Mint plant.

To propagate by seed, sow the Mint seeds on top of a sterile potting mix in a pot or seedling tray. Cover the seeds lightly with the soil and keep the soil moist. Covering the container with plastic wrap helps retain moisture. Germination takes place in 10 to 15 days. Once the seedlings are established, transplant to their own pot if needed.

Common Pests and Disease

Mint becomes susceptible to pests when stressed or unhealthy. Watch for spider mites, mealybugs, and aphids. Rinsing your plant with water in the shower often removes small infestations. 

Leaf rust is a common disease that turns the underside of the foliage orange. It is a result of high humidity or water on the leaves. Remove any affected leaves and ensure the foliage stays dry. 

Mint is a versatile herb used in both savory and sweet dishes. The plant is easy to grow and is ready to harvest in roughly eight weeks after germination. Add this tasty, edible plant to your houseplant collection for a burst of refreshing flavor in your favorite meals.

Mint Plant FAQ

Is Mint Toxic to Pets?

Yes, Mint is considered toxic to cats and dogs.

In What Climates Can I Grow Mint Outdoors?

Mint grows outdoors in USDA zones 3 to 11.

When Should I Repot My Mint?

Repot your Mint once every two years. Remove the plant from its pot and divide the root ball into two or more separate plants. Repot each new division in its own pot with the recommended soil type.

What Dishes Can I Use Mint in?

Use Mint to flavor such dishes as lamb, salads, fruit dishes, soups, and marinades.

How Do I Dry Mint Leaves?

 Cut bunches of Mint stems and tie them together. Hang the bunches upside down, in a cool, dry, and shady spot, for two to three days. The leaves are ready when they crumble once touched.