Watercress: Use, Properties, and Tradition

Nasturtium officinale R.Br., Family Cruciferae (formerly Brassicaceae), is commonly known as Watercress or Nasturtium.

The genus name Nasturtium is believed to derive from the Latin Nas = nose and tortus = twisted; due to the pungent odor that irritates the nostrils.

It is a perennial aquatic herbaceous plant that extends its branches over the water from the shore. It is widespread where water flows slowly or stagnates, and in wet areas in general. The roots are thin and whitish; the erect stem is hollow with thick fistulous branches and deeply divided imparipinnate leaves.

The flowers are small, as is typical of the family, and white with yellow anthers.

The fruit is a small slightly curved silique containing tiny brown seeds. It blooms from May to September.

It is a highly oxygenating plant that keeps the water always clean and free from algae or decay. It is an excellent indicator of the purity of the water in which it grows. Where it is found, the water is considered good. Once it was much more common, but now, due to water pollution, its distribution is significantly reduced.

There is an elegant ornamental plant (Tropaeolum majus), commonly called “Nasturtium,” which has nothing to do with the species we are describing.

Watercress aerial parts are used, with a weak odor and a bitter and pungent taste. This plant contains, analogously to other crucifers, glucosinolates, such as gluconasturtiin, 2-phenylisothiocyanate, and various nitriles. Particularly noteworthy is the presence of significant amounts of iodine and iron, vitamins (C and D), polysaccharides, and oligopeptides.

Its extracts are used for the treatment of respiratory tract conditions, especially in the presence of catarrh, and as cholagogues; as well as for diuretic action.

Pharmacological applications include thyroid rebalancing, biliary, pancreatic, endocrine, cutaneous, and pulmonary drainage.

For external use, it is used to treat alterations in skin pigmentation, and fresh leaves in poultices are popularly recommended for rheumatic inflammations. The sulphocyanic glucosides stimulate superficial skin circulation, are hyperemic, and, at the limit, irritant. Due to its revulsive properties, fresh juice, when rubbed, is excellent against baldness and as a scalp strengthener.

Contraindications concern cases of gastric and duodenal ulcers, or nephritis.

In cuisine, the leaves create a pleasant contrast with fatty or sweet foods, due to their very strong flavor reminiscent of arugula or mustard. Young shoots are used for salads. If collected in the wild, it is advisable to wash them carefully as they could transmit distomatosis (parasitic disease).

Known to the Romans, Watercress was directly harvested from the waters in which it thrived. Since the 17th century, the species has become the subject of exploitation in specific plots. The industrialization of cultivation began in Germany, near Erfurt, and then extended to other countries, assuming significant economic developments, especially in France where “Watercress farms” abound.

GIULIA CALDARELLI