Spearmint gets its name from its leaves, which compared to other mints are, as you guessed it, spear-shaped. Its botanical name is also taken from its pointy foliage – Mentha Spicata means “spike bearing” mint. It is in these delicious pointy leaves that the magic happens. The chemical that affects flavor and aroma in most mint plants is menthol, but spearmint actually has a minimal amount of this compound compared to other species and varieties. What sets spearmint apart is a chemical called carvone. This same chemical is found in aromatic favorites like dill and caraway, and it results in a spicier smell and taste. Combined with the other compounds in spearmint, it gives the herb a spicy, citrus, mint taste that this herb is prized for. Spearmint has been prized for a long time. The herb has been cultivated for culinary and medicinal purposes since the 1st century CE. It was mentioned in the bible as being so valuable, that, along with other spices, it was used to pay taxes. From the Middle East, it moved to Britain by way of Roman soldiers, where it enjoyed much success in monastic and then cottage gardens as it spread. In the 14th century a person most likely under a penname, John Gardiner, writes about spearmint in Feate of Gardening, the earliest known work on horticulture in the English Language. At the same time, it was a common ingredient in early kinds of toothpaste. By the 15th century it was known to help with stomach ailments, a use it is still known for today. In today’s world, it may not be monetarily valuable, but it is just as useful. From being used in cocktails, teas, mint jelly, and non-traditional medicines, to candles and oils, the plant’s use has spread as much as it does in the garden. Mint spreads by rhizomes and stolon. This growth makes the plant an excellent candidate for a container garden, but if you choose to plant in a bed or in the ground it should be spaced carefully allowing for spreading. Three feet apart is a good rule for spearmint which will allow time for your plant to mature to a sufficient height to harvest. Harvesting is best done before the plant goes to flower as the flavor will be concentrated in the leaves. If you harvest consistently you can get numerous hauls of leaves throughout the season and can then dry your mint for use throughout the year.
Light
Mints prefer full sun to partial shade. Spearmint can also be grown indoors under a grow light or on a bright windowsill.
Soil
Mints prefer a rich, moist, and well-drained soil. If potting, use a rich organic soilless mix.
Water
Water regularly, being careful not to overwater. Allow soil to go almost dry between watering, then soak thoroughly.
Temperature and Humidity
Spearmint thrives in USDA zones 4a to 11 and does not tolerate the cold. It does well indoors on a window or under a grow light.
Fertilizer
No need to fertilize, spearmint grows well on its own. But adding some additional nutrients post-harvest will rejuvenate for another haul.
Propagating Spearmint
Plants and seeds are both are readily available and equally easy to grow. Of course, seeds do take more effort, but they are more cost-efficient. Mint also grows easily from cuttings taken in the early spring using rooting hormone.
Growing Spearmint from Seeds
If you choose to start from seed start the process indoors eight to ten weeks before the last frost. Indoors, seeds will germinate in about two weeks. Keep the soil moist till there is germination and then mist daily, but take care not to saturate the soil. Having a fan next to your seedlings is a good idea to strengthen them. You can also sow directly outdoors in partially shaded, moist soil.
Identifying Spearmint
With care, spearmint can be distinguished from its close relatives. Apple mint, Mentha suaveolens, is easy to identify. It has softly rounded leaves, and its stems and leaves are covered in fine fluffy hairs called trichomes. The flowers of Apple mint are white or light pink, and the taste is less minty and almost fruity. Chocolate mint, Mentha x piperita ‘Chocolate’, has dark green leaves, is very fast growing and has rich reddish-brown stems. The smell and flavor are reminiscent of mint chocolate liqueur. Lavender Mint, Mentha x piperita ‘Lavender’, is as ornamental as it is aromatic. This beauty has large purple blooms and can reach heights to 36 inches. There is also a tricky version of spearmint known as curly-leaf mint, Mentha spicata ‘crispa’. This tall growing mint has all the traits of spearmint but with tightly curled leaves.
