Rorippa nasturtium-aquaticum (syn Nasturtium officinale), a useful perennial plant with a long season, which in some regions extends right through the year. (The garden flower nasturtium belongs to a different genus, Tropaeolum.)
Nasturtium is Latin for ‘nose twister’, referring to the plant's pungency. Watercress shares membership of the crucifer plant family with mustard, and both plants owe their pungency to substances of the same kind.
Watercress grows wild in Europe and Asia, and also in America since its introduction by European immigrants. Wild watercresses have been continuously popular since ancient times, not only for their pleasantly biting taste, but also for a wide variety of supposed health-giving properties. Thus the Greek general Xenophon made his soldiers eat it as a tonic. The Romans and Anglo-Saxons both ate it to avert baldness. Gerard (1633) recommended watercress as a remedy for that now forgotten disease, ‘greensickness of maidens’. Francis Bacon advised that it would restore youth to ageing women; and so on. In fact watercress does contain useful amounts of vitamins A and C, together with iron and other minerals, but no one has identified any mysterious curative substances in it.
Irish belief in the virtues of watercress (biolair) is especially strong. Theodora FitzGibbon (1983) points out that it is often mentioned in early manuscripts and books, for example as a ‘pure food for sages’, the holy men who customarily lived like hermits and might eat little but dry bread and watercress. Growing wild in the pure and unpolluted waters of W. Ireland, the watercress is of exceptional quality. It is also cultivated, probably since long ago. However, cultivation of the plant is commonly said to have begun at Erfurt in Germany, in the mid-16th century. It was not practised in England and the USA until the beginning of the 19th century.
Cultivars, whose appearance varies considerably, include hybrids, and a winter variety with attractively bronze-tinged leaves.
Watercress is usually eaten raw as a salad vegetable. The Romans ate it thus, dressed with pepper, cumin, mastic leaves, and garum. It can also be cooked, though this destroys its pleasant sharpness, and it makes a good soup; the French Potage cressonière is made from watercress and potatoes. Watercress is also much used as a garnish, especially for game.
In China, where it has a name meaning ‘western water vegetable’, watercress is commonly used in soup but is not eaten raw. Because both thrive in shallow water, it competes for space with rice in some areas.
Various other plants which are sometimes referred to as watercress or mixed with it or treated in the same ways include brooklime, Veronica beccabunga.
Alan Davidson was a distinguished author and publisher, and one of the world's best-known writers on fish and fish cookery. In 1975 he retired early from the diplomatic service—after serving in, among other places, Washington, Egypt, Tunisia, and Laos, where he was British Ambassador—to pursue a fruitful second career as a food historian and food writer extraordinaire. Among his popular books are Seafood of South-East Asia, North Atlantic Seafood, and Mediterranean Seafood. In 2003, shortly before his death, he was awarded the Erasmus Prize for his contribution to European culture.
FitzGibbon, Theodora (1983), Irish Traditional Food, London: Macmillan.
Gerard, John (1633), The Herbal, New York: Dover.
