Varieties of mint (Mentha) are some of the easiest and most popular herbs to grow. Plants in the mint family are very hardy perennials with vigorous growth habits. Mint, left to its own devices, will spread quickly and become a nuisance. However, it is very useful as a flavorful culinary herb and the plants can certainly be grown without much care. Just try to choose a spot where you won’t mind the rampant growth or grow it in a confined space, like a container or between paved areas.
Mint really wants to be a ground cover. The long branches grow upward and then flop over and root, spreading the plant wherever it can reach. The spikes of white or pinkish flowers are attractive, but brief. However, they do attract bees, butterflies, and even birds. Most mint plants are hybrids and will not grow true from seed.
Mints are easy to identify and not just because of their spicy scent. All members of the mint family have square stems.
Mentha is the genus for the mint family
- Peppermints (Mentha × piperita)
- Spearmints (Mentha spicata).
Mature Plant Size
Mature size will depend on the type of mint you are growing and how often you are snipping stems, but in general, expect your mint plants to reach:
- Height: 12 to 18 inches (30 to 45 centimeters).
- Width: 18 to 24 inches (45 to 60 centimeters).
Days to Harvest
You can start harvesting mint leaves once the plants have multiple stems that are about 6 to 8 inches long. This should take about two months from seed, or less time if you are buying plants. Don't harvest more than one-third of the plant at any time, to prevent weakening the plants and sending it into decline.
How to Harvest Mint
Snip sprigs and leaves as needed. If you don’t harvest your mint regularly, it will benefit greatly from a shearing mid-season. At some point, you will probably notice the stems getting longer and the leaves getting shorter. That’s the time to cut the plants back by one-third to one-half. This will encourage them to send out fresh new foliage again, with good sized leaves. You can do small patches at a time, if you have a lot of mint, and prolong the harvest season. Remember, all cuttings can be used, dried, or frozen for later use.
Mint plants prefer partial shade. You can grow it in full sun if you water it frequently.
USDA Hardiness Zones
Hardiness will depend on the variety you are growing, but mints are widely adaptable. Peppermint is very cold hardy, down to USDA Hardiness Zone 3. Spearmint handles the heat best, up to Zone 11.
Garden Design Suggestions for Mint Plants
Many mints work well in herbal lawns. They will need to be kept mowed, if you plan on walking on them, but this will help control their spread and the scent will make the work more pleasant.
If you don't want your mint plants spreading throughout the garden, it is best to plant mint in pots and keep them on patios or paved areas, because they will root and spread wherever they touch the ground. Even in pots, there will be more than enough to harvest and you won’t have the high maintenance of keeping the plants in check.
Suggested Mint Varieties to Grow
If you're ready to grow mint, try these varieties:
- Mentha piperita: Peppermint. This is the best for mint flavoring. (USDA Zones 5 through 11)
- Mentha piperita citrata cv.: Orange Mint. This is one of the tangiest of the fruit-flavored mints. (USDA Zones 4 through 11)
- Mentha suaveoloens: Apple Mint. It combines the flavors of apple and mint. (USDA Zones 5 through 11)
- Mentha suaveolens variegata: Pineapple Mint. This is a variegated offshoot of apple mint. (USDA Zones 6 through 11)
Mint Growing Tips
Mint is one of the few culinary herbs that grow well in shady areas, although it can handle full sun if kept watered.
Cuttings of mint will root easily in soil or water and mature plants can be divided and transplanted. However you can always start new plants from seed. Sow outdoors in late spring or start seed indoors about eight to 10 weeks before the last frost. Keep soil moist until the seed germinates. Mint seed germinates in 10 to 15 days. Seed-grown plants should reach harvestable size within two months.
Mint prefers a rich, moist soil with a slightly acidic pH between 6.5 and 7.0. If the soil is somewhat lean, top dress yearly with organic matter and apply an organic fertilizer mid-season, after shearing.
To contain the roots and limit spreading, you can grow mint in containers, above or sunk into the ground. Be careful to keep container mints from flopping over and touching the ground. Stems will root quickly if given the chance.
Caring for Mint Plants
There's not really much mint needs, besides moisture and a rich soil. It's pretty hard to kill a mint plant. The only maintenance required will be:
- Keeping your mint in check, so it doesn't take over
- Providing a moist soil
- Harvesting or shearing the plants to keep them lush with leaves
Pests and Problems of Mint
Mint can sometimes get rust, which appears as small orange spots on the undersides of leaves. Use an organic fungicide and try to allow plants to dry between waterings. Stressed plants may also be bothered by whitefly, spider mites, aphids, and mealybugs.