Garden cress is an herbaceous plant, of the same family as cabbages, turnips, mustard and arugula: that of the crucifers, hence the spice found in these products. Garden cress has fleshy stems and dark green leaves more or less large. It’s a plant that likes water.
The history of garden cress
The word “garden cress” appeared in the French language in 1130. It comes from the Francic kresso, which means creepy.
Cress would be a deformation of “orlénois”, a word derived from Orléans, a region where this plant was once cultivated. It appeared in the French language in the 13th century, and is used only in the expression “garden cress”.
However, “garden cress” is also widely used to designate several other plants in the family of Brassicaceae belonging to various botanical genera, including Barbara and Cardamine. Their fleshy stems and their more or less large leaves are edible. However, the watercress of Fontaine (Nasturtium officinale) is by far the plant people consume most.
It is not known with certainty where the garden cress originated. Some speak of Ethiopia, others from Western Asia. But it is believed it has been consumed for a long time by humans. Egyptians, Greeks and Romans knew it and appreciated the pungent taste. They also told about multiple medicinal properties. It spread very quickly in Europe as well as in the rest of the world. Cultivated all over gardens, however, it’s rarely the subject of large-scale crops, so it’s only occasionally found in supermarkets. Many types and cultivars are known, including a curly-leaf type and a wide-leaf.
It is not known much about the origin of the watercress, except in its natural habitat-current waters, streams, springs, and ditches grows wild on a vast territory from Europe to Central Asia. It has become naturalized in many other parts of the world, including the United States and Canada. This would be one of the most previously consumed leafy vegetables. In France, from the 13th century, the natural environment was being converted to increase production. Its own culture will only begin in the eighteenth century, in Germany. It is particularly popular in Britain, where, since the seventeenth century, it is considered an excellent depurative. In this country, the spring watercress cure always has many followers.
The cultivation of water watercress is similar to rice: it’s produced in shallow basins which are periodically dried and then flooded. The plant draws its nutrients mainly from the water, which must be rich in minerals, relatively fresh (10 °C or 11 °C), and of great purity. In commercial crops, this water is also the subject of rigorous health surveillance. Otherwise, people who consume watercress may contract fascialose, a parasitic disease which can have serious consequences.
Almost everywhere it’s produced, the harvest is done by hand in relatively difficult conditions. In order to counter this problem, it has been undertaken in recent years to cultivate it under a greenhouse, in hydroponics.
Everything is eaten in the watercress and the watercress: leaves, stems, flowers, young pods and seeds.
Garden cress health profile
Watercress is part of the family of the crucifers. There are different edible varieties of watercress. We will speak here of the watercress and of the garden cress. The first one has a rather peppery taste and a slightly stronger flavor than the second. The antioxidants of garden cress would prevent certain cancers and have beneficial effects on eye health.
The benefits of garden cress
Cancer. Some abundant compounds in the watercress, the isothiocyanates, would help to limit the development of the cancer11-13-16-29. They would be particularly effective in preventing the onset of lung cancer among smokers by inhibiting the action of a carcinogen present in cigarette smoke15. The watercress in the form of extract (watercress juice) would also protect the cells against the onset of colorectal cancer17. Regular consumption of raw watercress (85 g or about 2½ cups) would have an anti-cancer effect by reducing the damage caused by lymphocytes DNA 18.
Eye health. Several studies indicate that a steady intake of lutein and zeaxanthin is associated with a lower risk of macular degeneration, cataract6-7, and retinitis pigmentosa30. These two carotenoids, abundant in the watercress, accumulate into the maculate and retina of the eye6, thus protecting it from oxidative stress which could cause damage.
What does the garden cress contain?
The main antioxidant compounds of garden cress are carotenoids and flavonoids. They are found both in the garden cress and the watercress, in varying proportions. The antioxidants contained in garden cress protect the body cells from damage caused by free radicals and prevent the development of cardiovascular diseases, certain cancers and other agingrelated diseases1.
Carotenoids. Several in vitro research, among animals, as well as epidemiological studies show the consumption of foods rich in carotenoids would be related to a lower risk of being reached by certain types of cancers2-32, to develop cardiovascular diseases33-34 and would have a preventive effect against high blood pressure35. In addition, some carotenoids are precursors of vitamin A (i.e., the body transforms them into vitamin A, according to their needs).
Garden cress is particularly rich in beta-carotene. A portion of raw garden cress (1 cup or 250 ml) contains 2 times more of this carotenoid than the watercress. As a comparison, the carrot, recognized as one of the best sources of this carotenoid, contains 2 times more than garden cress3. With its antioxidant power, beta-carotene could improve certain immune system functions and be associated with the prevention of cancer4-5. A high consumption of beta-carotene would also have a protective effect against the development of cardiovascular diseases33-34. However, because the consumption of beta-carotene supplements did not yield conclusive results, foods containing beta-carotene should be preferred as they contain a host of other substances which can contribute to health benefits.
Watercress is exceptionally rich in lutein and zéaxanthine5. A portion of raw garden cress (1 cup or 250 ml) contains 3 times more of these carotenoids than the watercress and about 2 times more than a portion of raw spinach3. These compounds could help prevent certain cancers, including those of the breast and lung cancer, in addition to participating in the prevention of heart diseases6. However, studies on cardiovascular health are still limited and sometimes contracersial36.
Flavonoids. The main flavonoids of garden cress are flavonols, including kaempferol and quercetine9-10. The cress garden cress ranks among the richest foods in kaempferol, behind the kale containing the double, but in front of the chives, the raw broccoli and the chicory. The watercress contains 13 times less kaempferol than the garden cress, but it contains quercetine8. It contains about 3 times less than onion, one of the main sources of quercetin in food9-10.
Like the majority of the vegetables in the family of the brassicas, watercress contains glucosinolates. It would contain more than broccoli, cauliflower and many varieties of cabbage (white, red, savoy cabbage and bok choy)14. Garden cress contains about 4 times more than watercress14, but their concentration may vary according to environmental conditions (sun exposure, temperature). Glucosinolates have the ability to transform into active molecules (isothiocyanates) when the food containing it is chopped, chewed or in contact with the intestinal bacterial flora 12-15-37. Many of these molecules would help to limit the development of some cancers11-13. As cooking causes a significant loss of glucosinolates through boiling water20, it’s better to consume raw garden cress lightly cooked in a small amount of water or sautéed in the frying pan. The vegetable will retain all its bienfaits19.
The seeds of watercress: a nutritional richness to discover
The whole garden cress seeds are edible. In India, they are added to various culinary preparations. The Indians attribute several medicinal properties to them, including diuretic, antidiarrheal, tonic and … aphrodisiac effects. The belief is that they are also effective in combating hiccups.
Some parts of the grain, including endosperm and sound, contain essential proteins and fatty acids, mainly in the form of omega-3 (linolenic acid). The garden cress seeds also contain several minerals such as potassium, calcium phosphorus and iron. Their insoluble fiber content is particularly high. The nutritional quality of the cress watercress seeds is such that some researchers believe they would benefit from commercial exploitation as a functional ingredient23.
Very bio-available calcium in garden cress!
Watercress contains small amounts of calcium (44 mg per serving of 250 ml or 1 cup). However, it is interesting to note this calcium is bio-available, meaning a good proportion can be absorbed and used by the body. The absorption rate of the calcium present in the garden cress is 67%21, while the milk is absorbed at 32%, and the spinach, at 5%21-22. Milk remains the main source of calcium in the diet since a portion of 250 ml contains 315 mg. Although the milk provides 3 times more calcium usable by the organism than garden cress, the addition of garden cress to a balanced diet is an interesting way to increase its daily intake in this precious mineral.
No link between the crucifers and thyroid cancer
The crucifers, including garden cress, naturally contain thioglucosides. It was believed these substances were related to thyroid gland cancer among animals. However, studies of more than 5 000 people from many countries have shown high consumption of brassicas is not associated with a greater risk of thyroïde cancer24.
Vitamin K and anticoagulants
Watercress, especially the garden cress variety, contains a high amount of vitamin K, necessary among other things to coagulate the blood. Persons taking anticoagulant medications (Coumadin®, Warfilone® and Sintrom®, etc.) must adopt a diet with a relatively stable vitamin K content from one day to the next. Garden cress is part of a list of foods (asparagus, chard, broccoli, Brussels cabbage, spinach, etc.) must be consumed in a moderate way.
It is highly recommended for people under anticoagulation to consult a dietitian/nutritionist or physician to learn more about vitamin K food sources and to ensure the most stable daily intake is possible.
Lithiasis oxalocalciques and hyperoxaluria enteric
People at risk of urinary lithiasis (kidney stones consisting of oxalate and calcium, also known as renal gallstones) should limit their consumption of foods rich in oxalate. The same recommendation applies to persons with enteric hyperoxaluria following intestinal disorders, such as inflammatory bowel disease (celiac disease, Crohn’s disease). The oxalates are naturally found in several foods and the watercress contains large quantities. It is therefore preferable these people avoid consuming them.
Contamination of wild garden cress
The watercress, particularly those harvested in the wild, can be contaminated by the liver fluke or fasciola hepatica. It is a dangerous parasite causing a liver disease called fascioliasis or distomatose. In France, cases of contamination following the consumption of wild garden cress, and more rarely of raw commercial watercress, have been reported in scientific literature25. In this country, it is estimated that about 300 people are infected annually after consuming wild garden cress26.
In Western Europe, watercress is also the main source of human contamination in fasciola hepatica27. Cases have also been reported in India, Iran, North Africa and some South American countries. In North America, this type of infection is rather rare, with only a few cases were documented up to now28.
Choice and conservation
Watercress is found year-round in grocery stores, but the garden cress is rarer.
The leaves must be well green, firm, and show no signs of wilting. They must be washed well because they often contain sand or soil.
Attention to wild watercress
The harvest of watercress of wild water is strongly discouraged. Not only is there a risk of contracting fascioliasis, but watercress can also accumulate toxic doses of environmental pollutants, including arsenic.
The watercress does not keep long. It is better to consume it on the same day of purchase. If not, put it in the refrigerator after plunging the rods into a container of water and covered the head with a plastic bag or wrap it in a wet cloth before putting it in the fridge.
In Europe, seeds of garden cress and mustard seeds are germinated together in a proportion of two for one. It is enough to sow them very tight in a shallow bin filled with compost and placed on the edge of a window facing south. Keep the soil moist, but not soggy. The seeds will germinate very quickly and, after 10 days, you can harvest with scissors the young well green and pungent shoots. Repeat the operation regularly, especially during the winter.
In the garden, garden cress can sow very early in the spring, even when it is still freezing. It is recommended, however, to protect it by a agrotextile tissue if the temperature drops too low. Sow every two or three weeks to have seedlings all summer and fall. With age, the plant becomes tough and fibrous. You can then let it go up and harvest the young pods, perfectly edible, or wait until the seeds are ripe to use them as a condiment or use it for later sowing.
Under temperate climates, this plant is usually treated as an annual plant. Watercress is usually produced in water basins, but it can be grown in the garden if the soil is well moist.
Ecology and environment
More glucosinolates in cool and sunny weather
Several environmental factors influence the content of glucosinolates watercress, compounds which would help to limit the progression of cancer. Their concentration would increase substantially when exposed to the sun by 16 hours rather than 8 hours, in the presence of clear red light and at temperatures of 10 °C to 15 °C rather than 20 °C at 25 °C.
Like many monoculture, watercress can be a source of pollution. In the South of England, the rapid multiplication of watercress farms in recent years has contributed significantly to river pollution. One of the country’s largest watercress farms is accused of contributing to the pollution of the Bourne, a small stream of water that was once celebrated for its great purity water. Pesticides zinc and chlorine, which are used in this culture, are shown to threaten the environment. In France, it is believed that the pollution of the Juine River in the Essonne would be caused, at least in part, by the rinsing water used for the disinfection of the watercress cultivation basins. This water is loaded with residues of powerful products, such as formaldehyde. The trend towards the cultivation of organic watercress, considered to be less polluting, grows, but nevertheless remains marginal.