A detailed description of this familiar plant is hardly necessary. Its heart-shaped, finely toothed leaves tapering to a point, and its green flowers in long, branched clusters springing from the axils of the leaves are known to everyone. The soft, green leaves are 3 to 15 cm long and are borne oppositely on an erect, wiry, green stem.
Common nettle or stinging nettle (Urtica dioica) belongs to the genus Urtica. The latin name derived from the word “urere”, ‘to burn’, referring to the burning properties of the fluid it contains. The specific name of the plant, “dioica”, means ‘two houses’, referring to being a dioecious plant. The flowers are incomplete: the male flowers have stamens only, and the female flowers have only pistil or seed-producing organs. Usually a plant will bear either male or female flowers.
The flowers are adapted for wind-pollination. The nettle flowers from June to September. The plant reaches a height of 1 to 2 meters, dying down to the ground in winter. Its perennial yellow roots – rhizomes and runners – are creeping, so it multiplies quickly, making it difficult to get rid of.
The whole plant is covered with stinging hairs. Each sting is a very sharp, polished spine, which contains the venom, that causes irritation for a touch. The burning property of the juice is dissipated by heat, enabling the young shoots of the nettle, when boiled, to be eaten.