Peppermint, or Mentha × piperita, is super easy to grow. It’s an incredibly useful plant in the kitchen, with the aromatic leaves giving a refreshing flavor to food and drinks. The flowers attract beneficial wildlife to the garden, and peppermint plants are rumored to deter mice, rats and mosquitoes! Follow our peppermint growing guide to find out how to grow peppermint in your garden.
I. Appearance and Characteristics
Peppermint (Mentha × piperita) is a hybrid species of mint, a cross between watermint and spearmint. Indigenous to Europe and the Middle East, the plant is now widely spread and cultivated in many regions of the world. It is occasionally found in the wild with its parent species.
Peppermint was first identified in Hertfordshire, England, by a Dr. Eales, a discovery which John Ray published 1696 in the second edition of his book Synopsis Methodica Stirpium Britannicarum. He initially gave it the name Mentha spicis brevioribus et habitioribus, foliis Mentha fusca, sapore fervido piperis and later in his 1704 volume Historia Plantarum he called it Mentha palustris or Peper–Mint. The plant was then added to the London Pharmacopoeia under the name Mentha piperitis sapore in 1721.
It was given the name Mentha piperita in 1753 by Carl Linnaeus in his Species Plantarum Volume 2. Linnaeus treated Peppermint as a species, but it is now universally agreed to be a hybrid between Mentha viridis and Mentha aquatica with Mentha viridis itself also being a hybrid between Mentha sylvestris and Mentha rotundifolis.
It is an herbaceous, rhizomatous, perennial plant that grows to be 30–90 cm (12–35 in) tall, with smooth stems, square in cross section. The rhizomes are wide-spreading and fleshy, and bear fibrous roots. The leaves can be 4–9 cm (1+1⁄2–3+1⁄2 in) long and 1.5–4 cm (1⁄2–1+1⁄2 in) broad. They are dark green with reddish veins, with an acute apex and coarsely toothed margins. The leaves and stems are usually slightly fuzzy.
The flowers are purple, 6–8 mm (1⁄4–5⁄16 in) long, with a four-lobed corolla about 5 mm (3⁄16 in) diameter; they are produced in whorls (verticillasters) around the stem, forming thick, blunt spikes. Flowering season lasts from mid- to late summer. The chromosome number is variable, with 2n counts of 66, 72, 84, and 120 recorded. Peppermint is a fast-growing plant; once it sprouts, it spreads very quickly.
Peppermint typically occurs in moist habitats, including stream sides and drainage ditches. Being a hybrid, it is usually sterile, producing no seeds and reproducing only vegetatively, spreading by its runners.
II. How to Grow and Care
Sunlight
Peppermint can grow in full sun or partial shade. It can even tolerate some dappled shade, unlike most herbs.
Temperature and Humidity
Peppermint is unusually hardy and can survive light frosts but cannot endure extended cold snaps in cold climates, USDA Cold Hardiness Zones 5 and below. Its ideal growing conditions fall between 55 to 70 degrees Fahrenheit, but it can survive nicely above and below that range with little negative effect. If you expect temperatures to be on the warmer side, keep the soil moist while also watching for excess growth from humid conditions.
Watering
Consistently moist soil is the key to making sure your peppermint plant is happy and possesses tons of flavor. But be careful not to overdo it. Peppermint, like most mints, cannot tolerate standing water or soaking soil. Having soggy roots is a surefire way to kill or harm your plant.
Soil
The adaptability of peppermint is one of its best features; it is also one of its worst features, allowing it to grow almost anywhere, making it a nuisance. Peppermint’s ideal soil is rich, loamy, and moist, though it’s known to grow along trailside ditches and craggy outcrops—it can and will grow anywhere.
Fertilizing
Avoid fertilizing most herbs, especially plants in the genus Mentha. The flavor of herbs relies on the oils in their flowers and leaves. Accelerating their growth can lead to small profuse growth with many flowers and leaves and leggy stems rather than large, rich flowers and foliage with concentrated oils. You can often see this difference in the taste of homegrown compared to store-bought herbs.
Propagation
Mint might be one of the easiest plants to propagate from cuttings. Use sterile scissors or snips to cut a stem section four inches in length just below a leaf node. Remove the leaves below the node and immerse the cutting in distilled water and place it in a location with bright light and good air circulation.
Watch for root formation, which should occur within a few weeks. Let a good root system develop, then transplant the cutting into a pot fill with quality potting soil. Trim the top two inches from the plant to allow most of the energy to go into the root system. In a few weeks, you will have a thriving peppermint plant ready to be transplanted into a larger pot or into its new place in your garden.
Growing from Seed
Press the peppermint seeds on the surface of the seed starting mix. The seeds will be tiny, so use care and do not press too hard. You do not need to bury the seeds with soil. Keep the soil moist and germination will occur in five to ten days and perhaps sooner if the soil is kept warm with a heat mat. If you are direct sowing into the garden or when you are ready to transplant seedlings, wait until the threat of frost is past. Space the peppermint seedlings 18 to 24 inches apart.
Pests and Diseases
Peppermint is a resilient plant, and it will withstand attacks from a lot of pests and diseases. There are just a few worrying problems to look out for.
- Verticillium wilt can cause a peppermint plant to suddenly collapse, especially in hot weather. This is a fungal disease characterised by dark markings on (and in) the stem, as well as yellowing lower leaves. Remove and destroy any affected material, and ensure the peppermint plant receives adequate watering and a feed in the autumn.
- Unfortunately, these beautiful bugs are the destructive Mint leaf beetle. This pest will create holes in the leaves as they chew on the foliage. The leaves then don’t look attractive. However, peppermint is so vigorous that it will usually survive a nibble. If you’re worried, remove by hand and destroy.
- Rust can cause patches of orangey-yellow to appear on the plant. Dig up and destroy affected plants, and don’t propagate a new plant from another which has signs of rust.
III. Uses and Benefits
- Oil
Peppermint oil has a high concentration of natural pesticides, mainly pulegone (found mainly in M. arvensis var. piperascens (cornmint, field mint, or Japanese mint), and to a lesser extent (6,530 ppm) in Mentha × piperita subsp. notho) and menthone. It is known to repel some pest insects, including mosquitos, and has uses in organic gardening. It is also widely used to repel rodents.
- Research and health effects
Peppermint oil is under preliminary research for its potential as a short-term treatment for irritable bowel syndrome, and has supposed uses in traditional medicine for minor ailments. Peppermint oil and leaves have a cooling effect when used topically for muscle pain, nerve pain, relief from itching, or as a fragrance. High oral doses of peppermint oil (500 mg) can cause mucosal irritation and mimic heartburn.
Peppermint roots bioaccumulate radium, so the plant may be effective for phytoremediation of radioactively contaminated soil.
- Culinary and other uses
Fresh or dried peppermint leaves are often used alone in peppermint tea or with other herbs in herbal teas (tisanes, infusions). Peppermint is used for flavouring ice cream, candy, fruit preserves, alcoholic beverages, chewing gum, toothpaste, and some shampoos, soaps, and skin care products.
Menthol activates cold-sensitive TRPM8 receptors in the skin and mucosal tissues, and is the primary source of the cooling sensation that follows the topical application of peppermint oil.
IV. Cultivars
- Mentha × piperita ‘Chocolate Mint’ has blooms that open from the bottom up; its flavor is reminiscent of mint chocolate chip ice cream.
- Mentha × piperita ‘Citrata’ has a citrusy fragrance and is often called orange mint.
- Mentha × piperita ‘Crispa’ has a trailing habit with bright green crinkled leaves with tiny pale lavender blooms.
- Mentha × piperita ‘Lavender Mint’ is a fast-growing ground cover with reddish stems, dark green leaves, and profuse lavender blooms. It is ideal for use in savory meat and vegetable dishes.
- Mentha × piperita ‘Lime Mint’ has attractive bronze-green leaves what have a fresh lime-scent.
- Mentha × piperita ‘Variegata’ is a ground cover that produces spikes of violet flowers. Its green leaves have a creamy white variegation.
Find Where to Buy the Best Peppermint (Mentha x piperita)
[content-egg-block template=offers_logo_shipping cols_order=3,2,1,5,4 hide=badge visible=number border_color=info limit=8]