A tough, spreading perennial, the erect stems grow to 1.5 m (5 ft.) tall, on creeping roots. The stems and ovate, toothed, dull-green leaves are covered in stinging hairs. Inconspicuous greenish-yellow flowers (male and female on separate plants) appear in mid to late summer.
History and traditions
The common stinging nettle may be an unpopular weed, but over the centuries it has been put to many practical uses, remaining an important nutritious and medicinal herb. It was named Urtica by Pliny, from urere, to burn. Roman legionaries are said to have flailed themselves with nettles against the bone-chilling cold of a northern British winter. They even brought their own seeds, in case no plants grew locally. Whipping with nettles later became an established cure for rheumatism. The nettle was a common source of fiber (similar to that of flax and hemp) in many northern European nations. One of Hans Andersen’s fairy-tales tells of the Princess who wove nettle coats for swans. Above all, in former times, it made a valuable springtime pot-herb, tonic and anti-scorbutic after the deprivations of winter and was made into all manner of soups, puddings and porridges, as well as nettle beer.
Cultivation is usually unnecessary for domestic use as nettles are plentiful in wild and semi-wild areas and can be invasive in the garden. Grown as a crop they require moist, nitrogen-rich soil. Cut back before flowering to ensure a second crop of young leaves. Parts used Leafy stems cut in spring, before flowering, fresh for cookery, fresh or dried for infusions, extracts, lotions and ointments. Roots fresh or dried for decoctions for hair use.
Constituents include histamine and formic acid, which causes the sting, vitamins A, B, C, iron and other minerals. The high vitamin C content ensures proper absorption of iron and the juice is taken for anaemia. Its diuretic properties help rid the body of uric acid and it is taken as an infusion for rheumatism, arthritis and gout, or applied as a compress to ease pain. It also stimulates the circulation and is said to lower blood pressure. Decoctions of the root and leaves are applied for dry scalp, dandruff and are said to help prevent baldness.
Only fresh young leaves should be used, cooked as a spinach-like vegetable or made into soup. Leaves should not be eaten raw as they are highly irritant in this state.