Herb: Watercress


Latin name: Nasturtium officinale


Synonyms: Rorippa nasturtium-aquaticum, Sisymbrium nasturtium-aquaticum


Family: Cruciferae



Medicinal use of Watercress:

Watercress is very rich in vitamins and minerals, and has long been valued as a food and medicinal plant. Considered a cleansing herb, its high content of vitamin C makes it a remedy that is particularly valuable for chronic illnesses. The leaves are antiscorbutic, depurative, diuretic, expectorant, purgative, hypoglycaemic, odontalgic, stimulant and stomachic. The plant has been used as a specific in the treatment of TB. The freshly pressed juice has been used internally and externally in the treatment of chest and kidney complaints, chronic irritations and inflammations of the skin etc. Applied externally, it has a long-standing reputation as an effective hair tonic, helping to promote the growth of thick hair. A poultice of the leaves is said to be an effective treatment for healing glandular tumours or lymphatic swellings. Some caution is advised, excessive use of the plant can lead to stomach upsets. The leaves can be harvested almost throughout the year and are used fresh.

Description of the plant:



Plant:
Perennial


Height:
50 cm
(1 foot)

Flovering:
May to
October

Habitat of the herb:

Stream margins, ditches, flushes etc with moving water, usually in chalk or limestone areas.

Edible parts of Watercress:

Leaves - raw or cooked. Water cress is mainly used as a garnish or as an addition to salads, the flavour is strong with a characteristic hotness. It has a reputation as a spring tonic, and this is its main season of use, though it can be harvested for most of the year and can give 10 pickings annually. Some caution is advised if gathering the plant from the wild, see the notes above on toxicity. The leaves are exceptionally rich in vitamins and minerals, especially iron. A nutritional analysis is available. The seed can be sprouted and eaten in salads. A hot mustardy flavour. The seed is ground into a powder and used as a mustard. The pungency of mustard develops when cold water is added to the ground-up seed - an enzyme (myrosin) acts on a glycoside (sinigrin) to produce a sulphur compound. The reaction takes 10 - 15 minutes. Mixing with hot water or vinegar, or adding salt, inhibits the enzyme and produces a mild but bitter mustard.

Other uses of the herb:

The juice of the plant is a nicotine solvent and is used as such on strong tobaccos.

Propagation of Watercress:

Seed - sow spring in a pot emmersed to half its depth in water. Germination should take place within a couple of weeks. Prick out seedlings into individual pots whilst they are still small and increase the depth of water gradually until they are submerged. Plant out into a pond in the summer. Cuttings can be taken at any time in the growing season. Virtually any part of the plant, including a single leaf, will form roots if detached from the parent plant. Just put it in a container of water until the roots are well formed and then plant out in shallow water.

Cultivation of the herb:

Stream margins, ditches, flushes etc with moving water, usually in chalk or limestone areas.

Known hazards of Nasturtium officinale:

Whilst the plant is very wholesome and nutritious, some care should be taken if harvesting it from the wild. Any plants growing in water that drains from fields where animals, particularly sheep, graze should not be used raw. This is due to the risk of it being infested with the liver fluke parasite. Cooking the leaves, however, will destroy any parasites and render the plant perfectly safe to eat.

Plant information taken from the Plants For A Future.