Saturday, 23 September 2017

Stinging nettle (Urtica dioica)


The stinging nettle (Urtica dioica) is an herbaceous perennial plant in the Urticaceae family. Also known as nettle, leaf nettle and common nettle. An incredibly useful plant, it is known by many different regional names throughout the world. It is found in temperate regions including the British Isles where it flourishes forming dense thickets, particularly in disturbed ground.

Stinging nettle (Urtica dioica)

Growing methods

Nettles can be propagated by seed which is abundant. Sow in the spring or autumn. Germination may take some time. Dried mature seed which has been saved usually have a viability of three months. Alternatively, eight years if hermetically stored at -18°C. Germination of dry stored seed can be helped by warm stratification and alternating temperatures of 15°C and 25°C in the presence of light. Grow on in a rich potting compost.

Nettles can also be propagated vegetatively. The easiest propagation method is to simply acquire a clump of root and plant it. It will grow! There is no reason to be too fussy.

Nettles grows to just over a metre in height with white to yellowish flowers and can be picked most of the year. If cut at the base, they will come up again fairly quickly. This can be done three or four times per year, more if the conditions are right. They have a very tough rootstock and will readily spread.

Raw edible parts

The toothed leaves, young stems and young shoots can be eaten raw. We don’t have any information regarding the flowers and roots. The roots are certainly used in herbal medicine. Young plants under 30cm in height are best or the leaves only of older plants. The stems of older plants tend to get tough and stringy. However, you can use older plants, stems and all, for teas. Add nettles to smoothies or raw breads and make into a tea. Use 2 tsp of fresh nettle leaves per mug and infuse in hot water for about 10 mins. Drink immediately. Nettle tea can be used as a hair rinse or hair tonic. Nettles can be eaten raw if they are rolled up and crushed well into a ball first. Lightly cooked, they make a very good spinach subsitute and can be used in soup.

Other uses

Nettles are a very beneficial medicinal plant but can be used to make fibre, dye, paper, biomass, compost, a compost activator, a liquid plant feed, rennet and oil. This plant attracts certain species of butterflies and moths.

Nettle stems (leaves removed) ready to be stripped for fibre


Nettle fibre stripped from the outer stems

Issues

Stinging nettles will sting the skin, hence the name. The plant is armed with hairs that break off when touched. Formic acid, one of the chemicals present in the hair, is the cause of the initial stinging sensation. Other chemicals, including acetylcholine and histamine, prolong the agony so a numb tingling sensation can be felt for hours.

The 'sting' can be removed from the plant by hand crushing (use gloves), blending in a blender, wilting, cooking in water, making into tea or refrigerating.

There are repeated references to avoiding older nettles over 20-30 cm in height because they might produce kidney stones. American wild food expert Green Deane refutes this, claiming they are perfectly safe to eat.

Nettles are reportedly 'invasive' although why such a useful plant is considered a nuisance is anyone's guess.