Watercress, a green in the mustard family, is related to collards and kale, but has a life far away from the greens and pork of Southern-style cooking. Many people may associate watercress with beautiful sandwiches made for tea, but that’s only one area in which it shines.
Watercress is a European perennial herb, Nasturtium officinale, that has been naturalized in the US and is also cultivated. It is not related to the flower called nasturtium. In nature, it is often found near streams and creeks. It prefers to grow in shallow water and in cool weather. Watercress can be started from seed indoors and transferred outdoors to stream beds. It should be harvested before it blooms, and should be stored in the refrigerator, but not for too long. It needs to be thoroughly washed before using.
Known for its peppery taste, watercress is used as a green and as a garnish. It is often used to spice up sandwiches and appears frequently in salads, where it is usually combined with some vegetable or greens having a milder flavor or with citrus fruit. It can also be wilted and served as a green, used to season dumplings or savory mousse, or serve as an ingredient in soups ranging from Chinese watercress soup to cold cream of watercress soup to potato, leek, watercress soup.
Watercress is probably the most popular of the cresses, and for many people may be the only recognizable one. Others include pepper cress or sai yeung choy, Lepidum sativum; wintercress or yellow rocket, Barbarea vulgaris; and upland cress or land cress, Barbarea verna. Pepper cress is primarily grown in northwestern Europe, where it is harvested as sprouts. Wintercress is a hardy plant, high in vitamin C, that grows in Eurasia, North Africa, and the Appalachians. Land cress, unlike the other cresses, grows on land and is grown in southwestern Europe and England.
Historically, watercress was used to treat scurvy. Called “St. Patrick’s Cabbage” in Ireland, it is thought be some to be the plant designated by the term shamrock. The Greek general Xenophon made his soldiers eat it in the 4th century B.C., and the Romans tried it as a baldness prevention.