Family: Brassicaceae (Cruciferae), Nasturtium officinale
Source: Simon, J.E., A.F. Chadwick and L.E. Craker. 1984.
Herbs: An Indexed Bibliography. 1971-1980. The Scientific Literature
on Selected Herbs, and Aromatic and Medicinal Plants of the Temperate
Zone. Archon Books, 770 pp., Hamden, CT.
Watercress, Nasturtium officinale R. Br., is an aquatic
perennial herb native to Europe and naturalized in the United
States. Also known as green watercress and previously classified
as Rorippa Nasturtiumaquaticum (L.) Hayak, this succulent,
glabrous herb reproduces vegetatively forming roots at nodes.
The plant is characterized by 0.3 to 1 meter long floating and
ascending stems, green, fleshy leaflets, and small white flowers
The reported life zone of watercress is 6 to 27°C with an annual
precipitation of 0.3 to 4.2 meters and a soil pH of 4.3 to 8.3
(4.1-31). The species is found in areas of running water
adjacent to springs and riverbanks or on wet soil. The plant thrives
in full sunlight and cool water. Although susceptible to frost
injury in the autumn and spring, the submerged portion of the
plant will survive if the water remains unfrozen.
Careful attention to providing an adequate and good-quality
water supply is essential for successful commercial production.
Plants are generally grown in water tanks or beds having soil
bottoms and moving water. Beds of watercress can be maintained
for about ten years without resowing or replanting and require
about one month to reach a harvestable stage after a previous
harvest (14.1-1). Usually a number of beds are maintained
by growers to provide a continuous supply of the herb.
Fresh leaves of watercress are used as salad greens and as a garnish.
The leaves can be steamed and eaten as a vegetable. Watercress
is nutritious, being high in minerals, proteins, and vitamins.
As a medicinal plant, watercress has been traditionally considered
a diuretic, expectorant, purgative, stimulant, stomachic, and
tonic. It has also been used as a remedy against anemia, eczema,
kidney and liver disorders, tuberculosis, boils, warts, and tumors
Nasturtium microphyllum Boenn. ex Rchb., an occasionally
used salad plant formerly known as Rorippa microphylla
(Boenn. ex Rchb.) Hyl., both resembles and hybridizes with watercress.
The plant is more frost hardy than watercress and turns purplish
brown in autumn (14.1-12).
[Note: References listed above in parentheses can be found in
full in the original reference].
Last modified 6-Dec-1997