Watercress
Encyclopedia
Watercresses are fast-growing, aquatic or semi-aquatic, perennial plant
s native from Europe
to central Asia
, and one of the oldest known leaf vegetable
s consumed by human beings. These plant
s are members of the Family Brassicaceae
or cabbage
family, botanically related to garden cress
, mustard
and radish
— all noteworthy for a peppery, tangy flavour.
The hollow stems of watercress are floating, and the leaves are pinnately compound
. Watercresses produce small, white and green flower
s in clusters.
Nasturtium nasturtium-aquaticum (nomenclaturally invalid) and Sisymbrium nasturtium-aquaticum L. are synonyms of N. officinale.
Nasturtium officinale var microphyllum (Boenn. ex Reich.) Thellung is a synonym of N. microphyllum (ITIS, 2004). These species are also listed in some sources as belonging to the genus Rorippa
, although molecular evidence shows the aquatic species with hollow stems are more closely related to Cardamine than Rorippa.
Watercresses are not closely related to the flowers in the genus Tropaeolum (Family Tropaeolaceae), popularly known as "nasturtiums".
, calcium
and folic acid
, in addition to vitamins A
and C
. In some regions, watercress is regarded as a weed
, in other regions as an aquatic
vegetable
or herb
. Watercress crops grown in the presence of manure
can be a haven for parasites such as the liver fluke
Fasciola hepatica
.
Many benefits from eating watercress are claimed, such as that it acts as a stimulant
, a source of phytochemical
s and antioxidant
s, a diuretic
, an expectorant, and a digestive
aid. It also appears to have antiangiogenic cancer
-suppressing properties; it is widely believed to help defend against lung cancer
. A 2010 study conducted by the University of Southampton found that consumption of watercress may also inhibit the growth of breast cancer. The PEITC content of watercress inhibits HIF, which can inhibit angiogenesis
.
Due to its high iodine
content, watercress has a strengthening effect on the thyroid gland, thus it is beneficial for sufferers of hypothyroidism
.
In addition, watercress is a known inhibitor of the cytochrome P450 CYP2E1
, which may result in altered drug metabolism for individuals on certain medications (e.g., chlorzoxazone).
cultivation, thriving best in water that is slightly alkaline. It is frequently produced around the headwaters of chalk stream
s. In many local markets, the demand for hydroponically grown watercress exceeds supply. This is because, in part, cress leaves
are unsuitable for distribution in dried form, and can only be stored for a short period.
However (in the UK at least), the packaging used by supermarkets using sealed plastic bags under some internal pressure (a plastic envelope containing moisture and pressurised (inflated) to prevent crushing of contents) has allowed the distribution of watercress. This has allowed national availability with a once-purchased storage life of one to two days in chilled/refrigerated storage.
If unharvested, watercress can grow to a height of 50–120 cm. Also sold as sprouts
, the edible shoots are harvested days after germination.
Like many plants in this family, the foliage of watercress becomes bitter when the plants begin producing flowers.
New Market, Alabama
, was once known (in the 1940s) as the "Watercress Capital of the World" in America.
Watercress is often used in sandwiches, such as those made for afternoon tea
.
Watercress is grown in a number of counties of the UK, most notably Hertfordshire, Hampshire, Wiltshire and Dorset, although the first commercial cultivation was along the River Ebbsfleet in Kent
grown by William Bradbery
(horticulturist) in 1808. Alresford
, near Winchester, is often considered the watercress capital of Britain (to the extent that a steam railway line
is named after the famous local crop). In recent years, watercress has become more widely available in the UK, at least in the South-East, being stocked pre-packed in some supermarkets, as well as fresh by the bunch at farmers' markets and greengrocers. Value-added products, such as the traditional watercress soup and pesto, are increasingly easy to source.
Perennial plant
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...
s native from Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
to central Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, and one of the oldest known leaf vegetable
Leaf vegetable
Leaf vegetables, also called potherbs, green vegetables, greens, leafy greens or salad greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots...
s consumed by human beings. These plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s are members of the Family Brassicaceae
Brassicaceae
Brassicaceae, a medium sized and economically important family of flowering plants , are informally known as the mustards, mustard flowers, the crucifers or the cabbage family....
or cabbage
Cabbage
Cabbage is a popular cultivar of the species Brassica oleracea Linne of the Family Brassicaceae and is a leafy green vegetable...
family, botanically related to garden cress
Garden cress
Garden cress is a fast-growing, edible herb that is botanically related to watercress and mustard, sharing their peppery, tangy flavor and aroma...
, mustard
Mustard plant
Mustards are several plant species in the genera Brassica and Sinapis whose small mustard seeds are used as a spice and, by grinding and mixing them with water, vinegar or other liquids, are turned into the condiment known as mustard or prepared mustard...
and radish
Radish
The radish is an edible root vegetable of the Brassicaceae family that was domesticated in Europe, in pre-Roman times. They are grown and consumed throughout the world. Radishes have numerous varieties, varying in size, color and duration of required cultivation time...
— all noteworthy for a peppery, tangy flavour.
The hollow stems of watercress are floating, and the leaves are pinnately compound
Pinnate
Pinnate is a term used to describe feather-like or multi-divided features arising from both sides of a common axis in plant or animal structures, and comes from the Latin word pinna meaning "feather", "wing", or "fin". A similar term is pectinate, which refers to a comb-like arrangement of parts...
. Watercresses produce small, white and green flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s in clusters.
Nasturtium nasturtium-aquaticum (nomenclaturally invalid) and Sisymbrium nasturtium-aquaticum L. are synonyms of N. officinale.
Nasturtium officinale var microphyllum (Boenn. ex Reich.) Thellung is a synonym of N. microphyllum (ITIS, 2004). These species are also listed in some sources as belonging to the genus Rorippa
Rorippa
Rorippa is a flowering plant genus in the cabbage family , containing approximately 80 species native to Europe through central Asia, Africa, and North America. Rorippa species are annual to perennial herbs, usually with yellow flowers and a peppery flavour.Rorippa formerly included several species...
, although molecular evidence shows the aquatic species with hollow stems are more closely related to Cardamine than Rorippa.
Watercresses are not closely related to the flowers in the genus Tropaeolum (Family Tropaeolaceae), popularly known as "nasturtiums".
Health benefits and cancer defense
Watercress contains significant amounts of ironIron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
, calcium
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
and folic acid
Folic acid
Folic acid and folate , as well as pteroyl-L-glutamic acid, pteroyl-L-glutamate, and pteroylmonoglutamic acid are forms of the water-soluble vitamin B9...
, in addition to vitamins A
Vitamin A
Vitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal, that is necessary for both low-light and color vision...
and C
Vitamin C
Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...
. In some regions, watercress is regarded as a weed
Weed
A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...
, in other regions as an aquatic
Aquatic plant
Aquatic plants are plants that have adapted to living in aquatic environments. They are also referred to as hydrophytes or aquatic macrophytes. These plants require special adaptations for living submerged in water, or at the water's surface. Aquatic plants can only grow in water or in soil that is...
vegetable
Vegetable
The noun vegetable usually means an edible plant or part of a plant other than a sweet fruit or seed. This typically means the leaf, stem, or root of a plant....
or herb
Herb
Except in botanical usage, an herb is "any plant with leaves, seeds, or flowers used for flavoring, food, medicine, or perfume" or "a part of such a plant as used in cooking"...
. Watercress crops grown in the presence of manure
Manure
Manure is organic matter used as organic fertilizer in agriculture. Manures contribute to the fertility of the soil by adding organic matter and nutrients, such as nitrogen, that are trapped by bacteria in the soil...
can be a haven for parasites such as the liver fluke
Liver fluke
Liver flukes are a polyphyletic group of trematodes .Adults of liver flukes are localized in the liver of various mammals, including humans. These flatworms can occur in bile ducts, gallbladder, and liver parenchyma. They feed on blood...
Fasciola hepatica
Fasciola hepatica
Fasciola hepatica, also known as the common liver fluke or sheep liver fluke, is a parasitic flatworm of the class Trematoda, phylum Platyhelminthes that infects the livers of various mammals, including humans. The disease caused by the fluke is called fascioliasis . F...
.
Many benefits from eating watercress are claimed, such as that it acts as a stimulant
Stimulant
Stimulants are psychoactive drugs which induce temporary improvements in either mental or physical function or both. Examples of these kinds of effects may include enhanced alertness, wakefulness, and locomotion, among others...
, a source of phytochemical
Phytochemical
Phytochemicals are biologically active chemical compounds that occur naturally in plants . Phytochemicals are the molecules responsible for the color and organoleptic properties . For example, the deep purple color of blueberries and the smell of garlic...
s and antioxidant
Antioxidant
An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...
s, a diuretic
Diuretic
A diuretic provides a means of forced diuresis which elevates the rate of urination. There are several categories of diuretics. All diuretics increase the excretion of water from bodies, although each class does so in a distinct way.- Medical uses :...
, an expectorant, and a digestive
Digestive
Digestive may refer to:*Digestion, biological process of metabolism*Digestive biscuit, a British semi-sweet biscuit*Digestif, small beverage at the end of a meal...
aid. It also appears to have antiangiogenic cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
-suppressing properties; it is widely believed to help defend against lung cancer
Lung cancer
Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...
. A 2010 study conducted by the University of Southampton found that consumption of watercress may also inhibit the growth of breast cancer. The PEITC content of watercress inhibits HIF, which can inhibit angiogenesis
Angiogenesis
Angiogenesis is the physiological process involving the growth of new blood vessels from pre-existing vessels. Though there has been some debate over terminology, vasculogenesis is the term used for spontaneous blood-vessel formation, and intussusception is the term for the formation of new blood...
.
Due to its high iodine
Iodine
Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....
content, watercress has a strengthening effect on the thyroid gland, thus it is beneficial for sufferers of hypothyroidism
Hypothyroidism
Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone.Iodine deficiency is the most common cause of hypothyroidism worldwide but it can be caused by other causes such as several conditions of the thyroid gland or, less commonly, the pituitary gland or...
.
In addition, watercress is a known inhibitor of the cytochrome P450 CYP2E1
CYP2E1
Cytochrome P450 2E1 , a member of the cytochrome P450 mixed-function oxidase system, is involved in the metabolism of xenobiotics in the body. In humans, the CYP2E1 enzyme is encoded by the CYP2E1 gene...
, which may result in altered drug metabolism for individuals on certain medications (e.g., chlorzoxazone).
Watercress cultivation
Cultivation of watercress is practical on both a large scale and a garden scale. Being semi-aquatic, watercress is well-suited to hydroponicHydroponics
Hydroponics is a method of growing plants using mineral nutrient solutions, in water, without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium, such as perlite, gravel, mineral wool, or coconut husk.Researchers discovered in the 18th...
cultivation, thriving best in water that is slightly alkaline. It is frequently produced around the headwaters of chalk stream
Chalk stream
Chalk streams have characteristics which set them apart from watercourses associated with other rock types.Aside from those with an interest in the geological and ecological disciplines, the term chalk stream is most widely used among a small group of fly fishermen ,...
s. In many local markets, the demand for hydroponically grown watercress exceeds supply. This is because, in part, cress leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are unsuitable for distribution in dried form, and can only be stored for a short period.
However (in the UK at least), the packaging used by supermarkets using sealed plastic bags under some internal pressure (a plastic envelope containing moisture and pressurised (inflated) to prevent crushing of contents) has allowed the distribution of watercress. This has allowed national availability with a once-purchased storage life of one to two days in chilled/refrigerated storage.
If unharvested, watercress can grow to a height of 50–120 cm. Also sold as sprouts
Sprouting
Sprouting is the practice of germinating seeds to be eaten either raw or cooked.They are a convenient way to have fresh vegetables for salads, or otherwise, in any season and can be germinated at home or produced industrially...
, the edible shoots are harvested days after germination.
Like many plants in this family, the foliage of watercress becomes bitter when the plants begin producing flowers.
New Market, Alabama
New Market, Alabama
New Market is a census-designated place in Madison County, Alabama, United States, and is included in the Huntsville-Decatur Combined Statistical Area. As of the 2000 census, the population of the CDP is 1,864...
, was once known (in the 1940s) as the "Watercress Capital of the World" in America.
Watercress is often used in sandwiches, such as those made for afternoon tea
Tea (meal)
Tea can refer to any of several different meals or mealtimes, depending on a country's customs and its history of drinking tea. However, in those countries where the term's use is common, the influences are generally those of the former British Empire...
.
Watercress is grown in a number of counties of the UK, most notably Hertfordshire, Hampshire, Wiltshire and Dorset, although the first commercial cultivation was along the River Ebbsfleet in Kent
Kent
Kent is a county in southeast England, and is one of the home counties. It borders East Sussex, Surrey and Greater London and has a defined boundary with Essex in the middle of the Thames Estuary. The ceremonial county boundaries of Kent include the shire county of Kent and the unitary borough of...
grown by William Bradbery
William Bradbery
William Bradbery , an entrepreneur, was the first person in England to cultivate and sell watercress on a commercial basis.-Early life:...
(horticulturist) in 1808. Alresford
New Alresford
New Alresford or simply Alresford is a small town and civil parish in the City of Winchester district of Hampshire, England. It is situated some 12 km north-east of the city of Winchester and 20 km south-west of the town of Alton...
, near Winchester, is often considered the watercress capital of Britain (to the extent that a steam railway line
Watercress Line
The Watercress Line is the marketing name of the Mid-Hants Railway, a heritage railway in Hampshire, England, running from New Alresford to Alton where it connects to the National Rail network. The line gained its popular name in the days that it was used to transport locally grown watercress to...
is named after the famous local crop). In recent years, watercress has become more widely available in the UK, at least in the South-East, being stocked pre-packed in some supermarkets, as well as fresh by the bunch at farmers' markets and greengrocers. Value-added products, such as the traditional watercress soup and pesto, are increasingly easy to source.
External links
- Rorippa nasturtium-aquaticum (ITIS)
- www.watercressfestival.org - The Alresford Watercress Festival
- www.watercress.co.uk
- www.watercress.com
- www.watercressline.co.uk - The Watercress LineWatercress LineThe Watercress Line is the marketing name of the Mid-Hants Railway, a heritage railway in Hampshire, England, running from New Alresford to Alton where it connects to the National Rail network. The line gained its popular name in the days that it was used to transport locally grown watercress to...
/Mid-Hants Railway - GLANSIS Species Fact Sheet