Blackcurrant (botanical name, Ribes nigrum) is a perennially growing shrub that grows to a height of 2 meters (6 feet) and has woody branches without any spine. The leaves of this plant are potently aromatic and have a deep green hue with spots on the underside. Blackcurrant leaves are borne on elongated stalks and appear in alternating pairs or in the form of clusters. Each leaf of this plant is segregated into three to five curved lobes having jagged margins. The shrub produces greenish-white flowers during spring, which dangle from the axils in bunches. These flowers develop into recognizable little, yielding, and deep purple color berries.
There was a time when naturally growing blackcurrants were found extensively in the forested regions of northern Europe and people collected the fruits of the plant for use as food. Currently, this plant is cultivated widely together with many other varieties, counting green and white currants. Since long, people have been using the wild berries to make jams, pies, jellies and other such food items. In addition, brandy and wine made from blackcurrant fruits were once very popular. In the present times, cultivated blackcurrants are extensively employed by the food and beverages industries.
Blackcurrants are a particularly rich natural source of vitamin C and, hence, they often form the main ingredient in several drinks and cordials - some of which are intended to appeal to kids, thereby, ensuring that the children have a sufficient intake of vitamin C. In recent times, the French blackcurrant syrup cassis has turned out to be extremely well accepted. When included in chilled white wine, French blackcurrant syrup, it makes a refreshing summer aperitif, which is called ‘kir'. In addition, freshly picked blackcurrant leaves may also be immersed in white wine to add essence to the beverage. A cold infusion prepared with blackcurrant leaves is said to be extremely effective in quenching thirst during hot weather conditions.
Nevertheless, the blackcurrant is mainly valued for its therapeutic attributes. The herb's popular name, quinsy berries, has been derived from its effectiveness in treating inflammation of tonsils and this is a clear indication of the fact that in earlier times blackcurrants were used in the form of a home remedy to cure swollen and tender throats. In effect, the term ‘quinsy' denotes a type of tonsillitis. Therefore, it is little surprising that throat lozenges prepared from blackcurrant are available widely even today.
The juice of blackcurrant as well as the tea prepared with dried out blackcurrant leaves is also employed in the treatment of whooping cough in children. In fact, the leaves of this plant are cleansing and, therefore, make an outstanding gargle for curing bleeding gums and also to promote overall good oral hygiene. There was a time when the leaves of blackcurrant were prepared into a tea and used as an alternative to tea. Even now, the dried out leaves of blackcurrant are added to different other herbal tea blends.
Leaves, fruits and seed oil.
Blackcurrant is used for edible as well as therapeutic purposes. However, the plant is primarily valued for its remedial properties; for instance, blackcurrant leaves are an effective herbal medicine which has been traditionally employed to treat conditions like spasmodic cough, arthritis and diarrhea. Formulations of the leaves as well as the buds of this plant are taken internally to cure urinary disorders and rheumatism. The fruits of blackcurrant are effective in the form of dietary supplements during the season when cold and flu are rampant. Fresh ripened berries as well as the juice extracted from them are effective in treating mild cases of diarrhea. The oil yielded by the blackcurrant seeds has turned out to be well accepted as a substitute to the evening primrose oil.
The fruits or berries of blackcurrant are an excellent natural resource of minerals as well as vitamins, particularly vitamin C. These fruits possess diuretic as well as diaphoretic attributes and facilitate in augmenting the body's resistance power against infections. The leaves of this shrub are also diuretic, diaphoretic and cleansing (purifying). As the fruits stimulate the body to get rid of excessive fluids, they aid in lowering blood volume and, in this manner, lower blood pressure. An infusion prepared from the leaves of blackcurrant is employed to treat rheumatic pains, dropsy (earlier known as edema) and whooping cough. The infusion may also be applied topically to accelerate abscesses and cuts that are sluggish in healing. In addition, this infusion may also be employed in the form of a gargle to treat inflamed/ tender throats and mouth ulcers.
The leaves of blackcurrant are collected during the growing season of the plant and they can be used both fresh as well as dried. It is thought that an infusion prepared with the leaves augments cortisol secretion by the adrenal glands and, hence, it encourages the actions of the sympathetic nervous system. This action is likely to be particularly beneficial in treating any health problems associated with stress. In addition, an infusion prepared with the tender roots of the plant is beneficial in treating eruptive fevers. A decoction prepared with the bark of blackcurrant shrub has proved to be effective in treating dropsy, calculus and hemorrhoid tumors. Blackcurrant seeds are a vital source of gamma-linolenic acid - an unsaturated fatty acid that aids in the production of substances akin to hormones. When this process is obstructed in the body, it generally results in several health problems that have an effect on the nervous system, muscles of the uterus and metabolism.
The oil extracted from blackcurrant seed forms an active ingredient of many cosmetics and ointments for the skin. Often, this oil is blended with vitamin E with a view to thwart oxidation. Blackcurrant leaves also yield a yellow dye, while the fruit provides a blue or violet dye. In addition, the leaves of this plant are also employed for preserving vegetables.
The fruits (berries) of blackcurrant may be eaten raw or after cooking. Normally the fruits are approximately 10 mm across, while those of selected cultivars are larger in size. The completely ripened fruit has an outstanding aromatic taste. In fact, many people prefer to consume the berries raw, but they are generally cooked and used in making jams, pies and other such things. Even the leaves of blackcurrant are edible and the fresh tender leaves are used to add essence to soups. On the other hand, the dried out blackcurrant leaves serve as a substitute for tea. Occasionally, they are also included in other herbal tea mixtures.
Habitat and cultivation
As mentioned before, blackcurrant is indigenous to Europe, especially the central and northern regions, as well as the western regions of Asia. Over the years, this plant has been naturalized in North America. Earlier, blackcurrant was found growing naturally in damp soils, particularly in the humid forests in northern Europe as well as the mountainous counties of Cumbria and Yorkshire. Blackcurrant is extensively cultivated commercially as well as in horticultures for its tasty and therapeutically beneficial fruits or berries.
Blackcurrant can be grown without any difficulty in sandy loamy soil of reasonable quality that can retain moisture and is well drained. This plant loathes heavy clay, thin arid and chalky soils, but has the aptitude to thrive on all types of damp soil provided it contains profuse organic matters. It may be noted that blackcurrant needs a lot of nitrogen if it is to flourish. Blackcurrant has a preference for soil in the range of pH 6.7 to 7 and cannot endure acidic soils. Although plants of this species can tolerate shady positions to some extent, they do not produce sufficient fruits when grown in this condition. In addition, blackcurrant shrubs produce limited fruits when they are cultivated in places that are too windy. Although this plant has the ability to endure temperatures as low as -20°C, the blossoms of blackcurrant are damaged when the temperature falls to -1°C.
People inhabiting the temperate climatic regions of the world extensively cultivate blackcurrants for their edible and flavoured fruit. In effect, there are several named varieties of blackcurrants and majority of the fruits are produced by plants having a year-old wood. The trees/ shrubs are pruned every autumn and this involves getting rid of about one-third of the plant's stems from immediately over the ground level. During the pruning, the oldest stems of the plant having minimum new growths are gotten rid of because they bear the poorest fruits. The flowers of blackcurrant fertilize by themselves, but it has been seen that several cultivars have better fruiting when pollination is done by insects. Blackcurrant plants may shelter a period of ‘white pine blister rust' (one of the many diseases of pine caused by rust fungi) and, therefore, they should never be grown close to the pine trees. In addition, plants belonging to the genus Ribes are especially vulnerable to honey fungus.
Blackcurrant is primarily propagated by its seeds, which need to be sown immediately when they mature. The seeds should be sown in a cold frame in autumn; however, seeds that have been stored require stratification at temperatures ranging between 0°C and 5°C as soon as they ripen early in the year. In regular storage conditions, blackcurrant seeds continue to be viable for about 17 years or even more. When the seedlings have grown sufficiently large to be handled, prick them out individually and grow them in a cold frame during their first winter. The young plant can be transplanted in their permanent position outdoors during the latter part of the spring in the subsequent year. The plants may also be propagated from cuttings of semi-mature wood of the shrub in the size of 10 cm to 15 cm having a heel. These cuttings need to be grown in a frame during July-August.
Cuttings from mature wood of the growth during the present year, if possible having a heel of the growth of the previous year, may also be planted in a cold frame or in protected beds outdoors during the period between November and February.
Flavonoids (about 0.5%) are present, including derivatives of quercetin, kaempferol, myricetin, isorhamnetin and sakuranetin. Essential oil, 0.4% proanthocyanidins, diterpenes and ascorbic acid (0.3%) are reported to be present.
Therapeutically, blackcurrant is taken in the form of an herbal tea prepared using 2 grams to 4 grams of finely sliced leaves of the plant. This tea is drunk many times daily. In addition, blackcurrant leaves are occasionally added to diuretic tea blends as well as other herbal teas.