Stinging NettleUrtica dioica

Did you know?

• Urtica comes from the Latin urere, "to burn", for the plant's famous sting^{[4, 10]}.

• The sting comes from tiny hairs on the leaves and stems that inject a mix of histamine, acetylcholine, serotonin and formic acid into the skin^{[2, 4, 5]}.

• Cooking or thoroughly drying the leaves neutralizes the sting, which is why nettles can be eaten and brewed as tea^{[4, 5, 7]}.

• The species name dioica means "of two houses": male and female flowers usually grow on separate plants^{[5, 11]}.

• Nettle cloth is ancient: a 2,800-year-old textile from a Bronze Age grave in Denmark turned out to be woven from nettle fiber, probably grown in what is now Austria^[12].

• Nettle is the main caterpillar food plant of two familiar European butterflies, the peacock and the small tortoiseshell^{[13, 14]}.

Origins and history

Stinging nettle is a tough perennial that comes back each spring, usually growing 1 to 2 meters (3 to 7 feet) tall, with toothed leaves set in opposite pairs up the stem^{[5, 7, 8]}. It is at home in the cool temperate zone: native from Europe across Asia to Siberia and western China and in northwest Africa, and now naturalized from Alaska and Canada across the United States, in parts of South America and in New Zealand^{[5, 6]}.

Few wild plants have been so useful for so long. The Greek physicians Dioscorides and Galen both wrote about nettle leaf, and the Romans are said to have eaten nettles^{[2, 4]}. The young spring tops are cooked as a vegetable or stirred into soups, and heat takes away the sting^{[4, 5, 7]}. The dried leaves are brewed as a tea^{[2, 7]}, the fresh shoots have been brewed into nettle beer^{[4, 7]}, and in Cornwall the cheese Cornish Yarg is ripened in a coat of nettle leaves^[15]. Nettle stems gave a second harvest: a flax-like fiber for string and cloth^{[4, 5, 7]}, which Germany and Austria turned to for textiles during the First World War^[4]. The fiber also makes good paper, the leaves and stems give a lasting green dye, and the root a yellow one^[7]. The fresh young leaves are a real food, providing vitamin C, carotenoids and minerals^{[4, 8]}.

Today nettle leaf and nettle root are regarded as two different herbs. The European Medicines Agency has published separate herbal monographs for each, recognizing their long traditional use^{[1, 3]}.

Traditional uses

Nettle has a long, well-documented place in European herbal tradition, and the European Medicines Agency recognizes the traditional use of both its leaf and its root^{[1, 3]}.

• Spring greens and leaf tea

  The young tops are cooked as a vegetable, and the dried leaves are steeped in hot water to make a tea.^{[2, 7]}

• Urinary tract health

  Nettle leaf supports urinary tract health.*^{[1, 4]}

• Joint comfort

  Nettle leaf tea has traditionally been taken for joint comfort.*^{[1, 4]}

Plant compounds

Nettle leaf contains flavonoid glycosides, caffeic acid esters such as caffeoylmalic acid, plant sterols and plenty of chlorophyll, and the fresh leaves provide vitamin C and carotenoids^{[2, 4, 8, 9]}. The root is chemically different: its main compounds are plant sterols, lectins and polysaccharides^{[4, 8]}.