Water Mint
Mentha aquatica
Family: Lamiaceae or Labiatae
What it is like
Mentha aquatica is a PERENNIAL growing to 1 m (3ft 3in) by 1 m (3ft 3in). See above for USDA hardiness. It is hardy to UK zone 6 and is not frost tender. It is in flower from July to October, and the seeds ripen from September to October. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and can grow in heavy clay soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist or wet soil and can grow in water.
Height (m): 1
Where it is found
Swamps, fen, marshes, near rivers, streams and ponds, in wet woods.
Europe, including Britain, south and east to N. Africa and southwest Asia Also in S. Africa, Madeira
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 3
Leaves - raw or cooked. A strong distinctive peppermint-like fragrance. Used as a flavouring in salads or cooked foods. The leaves are too pungent for most people to use as a flavouring. A herb tea is made from the leaves.
Condiment: the various plants that are used as flavourings, either as herbs, spices or condiments.
Tea: the various herb teas that can be used in place of tea, plus the genuine article.
Medicine
Rating: 3
The leaves are anodyne, antiseptic, antispasmodic, astringent, carminative, cholagogue, diaphoretic, emetic, refrigerant, stimulant, stomachic, tonic and vasodilator. A tea made from the leaves has traditionally been used in the treatment of fevers, headaches, digestive disorders and various minor ailments. It is also used as a mouth-wash and a gargle for treating sore throats, ulcers, bad breath etc. The leaves are harvested as the plant comes into flower and can be dried for later use. The essential oil in the leaves is antiseptic, though it is toxic in large doses.
Anodyne: Relieves pain, it is milder than an analgesic.
Antidiarrhoeal: Provides symptomatic relief for diarrhoea. Also see Astringent.
Antiseptic: Preventing sepsis, decay or putrefaction, it destroys or arrests the growth of micro-organisms.
Antispasmodic: Relaxes muscular spasms and cramps, calming nervous irritation.
Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.
Carminative: Reduces flatulence and expels gas from the intestines.
Cholagogue: Increases the flow of bile and its discharge from the body.
Diaphoretic: Induces perspiration.
Emetic: Induces vomiting.
Refrigerant: Cools the body.
Stimulant: Excites or quickens activity of the physiological processes. Faster acting than a tonic but differing from a narcotic in that it does not give a false sense of well-being.
Stomachic: Aids and improves the action of the stomach.
Tonic: Improves general health. Slower acting than a stimulant, it brings steady improvement.
Vasodilator: Widens the blood vessels, thereby reducing blood pressure.
Other
Rating: 3
The plant repels flies, mice and rats. It has a pleasant, fresh scent and was formerly used as a strewing herb and has been strewn in granaries to keep mice and rats off the grain. The plant, harvested before flowering, yields about 0.8% essential oil. The fresh or dried plant is very good when used in herbal baths and can also be used in herb pillows. Water garden.
Repellent: Plants that are said to deter but not necessarily kill various mammals, birds, insects etc.
Strewing: Plants, usually aromatic, that are strewn on the floor to give a nice smell, repel insects etc.
Food Forest: Plants for Edible Forest Gardens and Food Forests.
Scented Plants: Plants noted for their scent
How it is grown
Succeeds in most soils and situations so long as the soil is not too dry. Grows well in heavy clay soils. A sunny position is best for production of essential oils, but it also succeeds in partial shade. Plants can grow in water up to 15cm deep. Most mints have fairly aggressive spreading roots and, unless you have the space to let them roam, they need to be restrained by some means such as planting them in containers that are buried in the soil. Hybridizes freely with other members of this genus. The whole plant, especially when bruised, has a pungent aroma of bergamot. The flowers are especially attractive to bees and butterflies. A good companion for brassicas. Members of this genus are rarely if ever troubled by browsing deer.
Propagating it: Seed - sow spring in a cold frame. Germination is usually fairly quick. Prick out the seedlings into individual pots when they are large enough to handle and plant them out in the summer. Mentha species are very prone to hybridisation and so the seed cannot be relied on to breed true. Even without hybridisation, seedlings will not be uniform and so the content of medicinal oils etc will vary. When growing plants with a particular aroma it is best to propagate them by division. Division can be easily carried out at almost any time of the year, though it is probably best done in the spring or autumn to allow the plant to establish more quickly. Virtually any part of the root is capable of growing into a new plant. Larger divisions can be planted out direct into their permanent positions. However, for maximum increase it is possible to divide the roots up into sections no more than 3cm long and pot these up in light shade in a cold frame. They will quickly become established and can be planted out in the summer.
Best place to grow: Woodland Garden Dappled Shade; Shady Edge; Pond; Bog Garden;
Habit: Perennial
Hardiness: 5-9
Growth:
Soil: Light (sandy), medium, heavy (clay)
Shade: Semi-shade, no shade
Moisture: Moist, wet, water
Things to keep in mind
Although no records of toxicity have been seen for this species, large quantities of some members of this genus, especially when taken in the form of the extracted essential oil, can cause abortions so some caution is advised.
Its other names
Local names
Synonyms
M. hirsuta.