Watercress or yellowcress (''Nasturtium officinale'') is a species of aquatic flowering plant in the cabbage family

Brassicaceae Brassicaceae () or (the older) Cruciferae () is a medium-sized and economically important family of flowering plants commonly known as the mustards, the crucifers, or the cabbage family. Most are herbaceous plants, while some are shrubs. The l ...

. Watercress is a rapidly growing

perennial plant A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

native to Europe and Asia. It is one of the oldest known

leaf vegetable Leaf vegetables, also called leafy greens, pot herbs, vegetable greens, or simply greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots. Leaf vegetables eaten raw in a salad can be called salad ...

s consumed by humans. Watercress and many of its relatives, such as garden cress, mustard,

radish The radish ('' Raphanus raphanistrum'' subsp. ''sativus'') is an edible root vegetable of the family Brassicaceae that was domesticated in Asia prior to Roman times. Radishes are grown and consumed throughout the world, being mostly eaten ra ...

, and

wasabi Wasabi ( Japanese: , , or , ; ''Eutrema japonicum'' or ''Wasabia japonica'') or Japanese horseradish is a plant of the family Brassicaceae, which also includes horseradish and mustard in other genera. The plant is native to Japan and the Russ ...

, are noteworthy for their piquant flavors. The hollow stems of watercress float in water. The leaf structure is

pinnately compound Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and in ...

. Small, white, and green

inflorescences An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed on ...

are produced in clusters and are frequently visited by insects, especially

hoverflies Hover flies, also called flower flies or syrphid flies, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, whi ...

, such as '' Eristalis'' flies.

Taxonomy

Watercress is listed in some sources as belonging to the genus '' Rorippa'', although molecular evidence shows those aquatic species with hollow stems are more closely related to '' Cardamine'' than ''Rorippa''. Despite the Latin name, watercress is not particularly closely related to the flowers popularly known as nasturtiums ('' Tropaeolum majus''). ''T. majus'' belongs to the family Tropaeolaceae, a

sister taxon In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

to the Brassicaceae within the order

Brassicales The Brassicales (or Cruciales) are an order of flowering plants, belonging to the eurosids II group of dicotyledons under the APG II system. One character common to many members of the order is the production of glucosinolate (mustard oil) compo ...

Distribution

In some regions, watercress is regarded as a

weed A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place", or a plant growing where it is not wanted.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. ...

, in other regions as an aquatic

vegetable Vegetables are parts of plants that are consumed by humans or other animals as food. The original meaning is still commonly used and is applied to plants collectively to refer to all edible plant matter, including the flowers, fruits, stems ...

herb In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicina ...

. Watercress has grown in many locations around the world. In the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...

, watercress was first commercially cultivated in 1808 by the horticulturist William Bradbery along the River Ebbsfleet in

Kent Kent is a county in South East England and one of the home counties. It borders Greater London to the north-west, Surrey to the west and East Sussex to the south-west, and Essex to the north across the estuary of the River Thames; it faces ...

. Watercress is now grown in several counties of the

, most notably

Hampshire Hampshire (, ; abbreviated to Hants) is a ceremonial county, ceremonial and non-metropolitan county, non-metropolitan counties of England, county in western South East England on the coast of the English Channel. Home to two major English citi ...

Dorset Dorset ( ; archaically: Dorsetshire , ) is a county in South West England on the English Channel coast. The ceremonial county comprises the unitary authority areas of Bournemouth, Christchurch and Poole and Dorset. Covering an area of ...

Wiltshire Wiltshire (; abbreviated Wilts) is a historic and ceremonial county in South West England with an area of . It is landlocked and borders the counties of Dorset to the southwest, Somerset to the west, Hampshire to the southeast, Gloucestershir ...

, and Hertfordshire. The town of Alresford, near Winchester, is considered to be the nation's watercress capital. It holds a Watercress Festival that brings in more than 15,000 visitors every year and a preserved steam railway line has been named after the local crop.

Uses

Watercress leaves, stems, and fruit can be eaten raw.

Tradition

Ancient Romans In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 B ...

thought eating it would cure mental illness. Twelfth-century mystic

Hildegard of Bingen Hildegard of Bingen (german: Hildegard von Bingen; la, Hildegardis Bingensis; 17 September 1179), also known as Saint Hildegard and the Sibyl of the Rhine, was a German Benedictine abbess and polymath active as a writer, composer, philosopher ...

thought eating it steamed and drinking the water would cure jaundice or fever. Watercress was eaten by Native Americans. Some Native Americans used it to treat

kidney The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; bloo ...

illnesses and

constipation Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel moveme ...

, and it was thought by some to be an

aphrodisiac An aphrodisiac is a substance that increases sexual desire, sexual attraction, sexual pleasure, or sexual behavior. Substances range from a variety of plants, spices, foods, and synthetic chemicals. Natural aphrodisiacs like cannabis or coca ...

. Early African Americans used the plant as an

abortifacient An abortifacient ("that which will cause a miscarriage" from Latin: '' abortus'' "miscarriage" and '' faciens'' "making") is a substance that induces abortion. This is a nonspecific term which may refer to any number of substances or medications ...

; it was believed to cause sterility as well.

Nutrition

The new tips of watercress leaves can be eaten raw or cooked, although caution should be used when collecting these in the wild because of parasites such as '' giardia''. Watercress is 95% water and has low contents of

carbohydrates In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or may ...

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...

, fat, and

dietary fiber Dietary fiber (in British English fibre) or roughage is the portion of plant-derived food that cannot be completely broken down by human digestive enzymes. Dietary fibers are diverse in chemical composition, and can be grouped generally by th ...

. A 100-gram serving of raw watercress provides 11

calories The calorie is a unit of energy. For historical reasons, two main definitions of "calorie" are in wide use. The large calorie, food calorie, or kilogram calorie was originally defined as the amount of heat needed to raise the temperature of o ...

, is particularly rich in

vitamin K Vitamin K refers to structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. The human body requires vitamin K for post-synthesis modification of certain proteins that are required for blood coagulat ...

(238% of the

Daily Value The Reference Daily Intake (RDI) used in nutrition labeling on food and dietary supplement products in the U.S. and Canada is the daily intake level of a nutrient that is considered to be sufficient to meet the requirements of 97–98% of health ...

, DV), and contains significant amounts of

vitamin A Vitamin A is a fat-soluble vitamin and an essential nutrient for humans. It is a group of organic compounds that includes retinol, retinal (also known as retinaldehyde), retinoic acid, and several provitamin A carotenoids (most notably ...

vitamin C Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) a ...

riboflavin Riboflavin, also known as vitamin B2, is a vitamin found in food and sold as a dietary supplement. It is essential to the formation of two major coenzymes, flavin mononucleotide and flavin adenine dinucleotide. These coenzymes are involved in e ...

vitamin B6 Vitamin B6 is one of the B vitamins, and thus an essential nutrient. The term refers to a group of six chemically similar compounds, i.e., "vitamers", which can be interconverted in biological systems. Its active form, pyridoxal 5′-phosphat ...

calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar t ...

, and

manganese Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy u ...

(table).

Phytochemicals and cooking

As a cruciferous vegetable, watercress contains isothiocyanates that are partly destroyed by boiling, while the content of

carotenoid Carotenoids (), also called tetraterpenoids, are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, cor ...

s is slightly increased. Steaming or

microwave cooking A microwave oven (commonly referred to as a microwave) is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range. This induces polar molecules in the food to rotate and produce th ...

retains these

phytochemical Phytochemicals are chemical compounds produced by plants, generally to help them resist fungi, bacteria and plant virus infections, and also consumption by insects and other animals. The name comes . Some phytochemicals have been used as poison ...

Cultivation

Watercress cultivation is practical on both a large scale and a garden scale. Being semi-aquatic, watercress is well-suited to

hydroponic Hydroponics is a type of horticulture and a subset of hydroculture which involves growing plants, usually crops or medicinal plants, without soil, by using water-based mineral nutrient solutions in aqueous solvents. Terrestrial or aquatic plan ...

cultivation, thriving best in water that is slightly

alkaline In chemistry, an alkali (; from ar, القلوي, al-qaly, lit=ashes of the saltwort) is a basic, ionic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a ...

. It is frequently produced around the headwaters of chalk streams. In many local markets, the demand for hydroponically grown watercress exceeds supply, partly because cress leaves are unsuitable for distribution in dried form and can only be stored fresh for about 2-3 days. Also sold as sprouts, the edible shoots are harvested days after germination. If unharvested, watercress can grow to a height of .

Concerns

Watercress crops grown in the presence of

manure Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nut ...

can be an environment for

parasite Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of lif ...

s such as the

liver fluke Liver fluke is a collective name of a polyphyletic group of parasitic trematodes under the phylum Platyhelminthes. They are principally parasites of the liver of various mammals, including humans. Capable of moving along the blood circulation, ...

, '' Fasciola hepatica''. By inhibiting the cytochrome P450 enzyme CYP2E1, compounds in watercress may alter

drug metabolism Drug metabolism is the metabolic breakdown of drugs by living organisms, usually through specialized enzymatic systems. More generally, xenobiotic metabolism (from the Greek xenos "stranger" and biotic "related to living beings") is the set o ...

in individuals on certain medications such as chlorzoxazone. Due to its fast-growing nature and

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species adv ...

status, ''Nasturtium officinale'' is prohibited in

Illinois Illinois ( ) is a state in the Midwestern United States. Its largest metropolitan areas include the Chicago metropolitan area, and the Metro East section, of Greater St. Louis. Other smaller metropolitan areas include, Peoria and Roc ...

References

External links

''Rorippa nasturtium-aquaticum''
(ITIS)
GLANSIS Species Fact Sheet
{{Taxonbar, from=Q150452 Asian vegetables Nasturtium (genus) Freshwater plants Herbs Leaf vegetables Medicinal plants Perennial vegetables Flora of Europe Flora of temperate Asia