Don't be confused by the species name nasturtium officinale - water cress is closely related to garden cress and is a member of the cabbage (brassicaceae) family of brassicales, whereas nasturtium is the best known member of the quite different tropaeolaceae family. But they share an instant (if short-lived) peppery, tangy flavour.
Water cress plants
Water cress leaves and flowers
Water cress leaves
Water cress grows wild across Europe and was included by Charlemagne in his Capitulare de Villis as one of the herbs to be grown in his Imperial gardens and in monasteries. Although water cress is found wherever water is available, it is not grown commercially. Water cress is sometimes found in garden markets, originating from small-scale backyard cultivation or from collection in the wild.
Brassicaceae (cabbage family).
Water cress and its relatives display a spicy aroma and a refreshing, peppery-pungent taste lasting only a few seconds. The aroma of water cress is generally considered to be superior to that of other cresses The aroma components are volatile and susceptible to both heat and moisture, so garden and other cresses are always used fresh and should not be boiled, baked or otherwise heated.
For the origin of cress, see garden cress. Water cress bears in most languages an attribute meaning "water", "well" or "fountain" (Indonesian air, Finnish vesi, German wasser, Italian acqua, Russian voda, Greek nero, German brunnen and French fontain.
The genus name "nasturtium" (used by the Romans for several cress-like plants and especially for garden cress) probably derives from nasi-tortium "nose pain" from nasus "nose" and the verb torquere "torment" and refers to the sharp, pungent aroma. Species name officinale refers to a "drug", "medicine" or "plant".
Water cress and other cresses are considered interchangeable in the kitchen and are popular in Europe and North America where they are used for spreads (especially those based on cottage cheese) and salads. In Europe, cress leaves are not commonly combined with other fresh herbs but they are compatible with the fines herbes of French cuisine and may be used together with each of them.
The disadvantages of water cress are that the plant must be gathered in the wild and the leaves cannot be dried and are only rarely traded. Hydroponic cultivation is possible but not commercially viable.