Watercress is a fast-growing, aquatic or semi-aquatic, perennial plant native to Europe and Asia and one of the oldest known leaf vegetables consumed by humans. It is botanically related to garden cress, mustard and radish which are all noted for their peppery, tangy flavour. Watercress is closely related to nasturtiums and it has hollow stems that float on the water. It produces white and green flowers that grow in clusters.
Watercress can be grown commercially or on a small scale in a garden and can be found in chalk streams as it thrives in slightly alkaline water.
Apart from growing naturally in streams, Watercress can be found in ditches, ponds and all the places where there is water. It is grown for the leaves that are mainly used in the form of salad greens or dressings. The plant has a hollow branching stem that is connected to a crawling rootstock, about one to two feet in length which usually pulls out along with the leaves above the surface of the water. The leaves of watercress are smooth and slightly plump having one to four pairs of little oblong or disk-shaped leaflets and are a deep green colour. Watercress must be fresh when bought as it does not dry and it is marketed in sealed plastic bags that have some moisture in them. It is essential not to crush the leaves and should only be stored for one or two days in the fridge. Once flowers start to appear on the Watercress plant, the plant becomes bitter and so is unsuitable for eating.
In some regions, Watercress is regarded as a weed; in other regions as an aquatic vegetable or herb. Watercress has been grown in many locations around the world and was first commercially cultivated in the early 1800’s. It is very popular in the UK and the town of Alresford, near Winchester, 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.
Watercress contains significant amounts of iron, calcium, iodine, and folic acid, in addition to vitamins A and C. Because it is relatively rich in Vitamin C, Watercress was suggested by English military surgeon John Woodall as a remedy for scurvy. Many benefits from eating watercress are claimed, such as that it acts as a stimulant, a diuretic, an expectorant, and a digestive aid. It also appears to have anti-angiogenic cancer-suppressing properties and it is widely believed to help defend against lung cancer and may also inhibit the growth of breast cancer. Watercress is also believed to stop bleeding, when mixed with vinegar. A special soup prepared with Watercress is among the most popular medications among the Chinese. This soup is used to cure swollen gums, bad breath and ulcers in the mouth. An infusion prepared from Watercress is also a proven traditional as well as an effectual remedy for dermatitis and eczema.
Watercress is popular not only as a garnish, but is used in salads, sandwiches, casseroles and soups and it adds a fast and spicy flavour to all these preparations.
Despite its good points, Watercress crops can be a haven for parasites such as the liver fluke, which is why it is essential that this herb is eaten fresh and washed well prior to use.