''' The Roselle (Hibiscus sabdariffa) is a species of hibiscus native to the Old World tropics. It is an annual or perennial herb or woody-based subshrub, growing to 2–2.5 m tall. The leaves are deeply three- to five-lobed, 8–15 cm long, arranged alternately on the stems.
The flowers are 8–10 cm in diameter, white to pale yellow with a dark red spot at the base of each petal, and have a stout fleshy calyx at the base, 1.5–2 cm wide, enlarging to 3–3.5 cm, fleshy and bright red as the fruit matures. It is an annual plant, and takes about six months to mature.
The red calyces of the plant are increasingly exported to America and Europe, where they are used as food colourings. Germany is the main importer. It can also be found in markets (as flowers or syrup) in some places such as France, where there are Senegalese immigrant communities. The green leaves are used like a spicy version of spinach. They give flavour to the Senegalese fish and rice dish thiéboudieune. Proper records are not kept, but the Senegalese government estimates national production and consumption at 700 metric tons per year. Also in Myanmar their green leaves are the main ingredient in making chin baung kyaw curry.
In East Africa, the calyx infusion, called "Sudan tea", is taken to relieve coughs. Roselle juice, with salt, pepper, asafetida and molasses, is taken as a remedy for biliousness.
The heated leaves are applied to cracks in the feet and on boils and ulcers to speed maturation. A lotion made from leaves is used on sores and wounds. The seeds are said to be diuretic and tonic in action and the brownish-yellow seed oil is claimed to heal sores on camels. In India, a decoction of the seeds is given to relieve dysuria, strangury and mild cases of dyspepsia. Brazilians attribute stomachic, emollient and resolutive properties to the bitter roots.
In Africa, especially the Sahel, roselle is commonly used to make a sugary herbal tea that is commonly sold on the street. The dried flowers can be found in every market. In the Caribbean the drink is made from the fresh fruit, and it is considered an integral part of Christmas celebrations. The Carib Brewery Trinidad Limited, a Trinidad and Tobago brewery, produces a Shandy Sorrel in which the tea is combined with beer.
In Thailand, Roselle is drunk as a tea, believed to also reduce cholesterol. It can also be made into a delicious wine - especially if combined with Chinese tea leaves - in the ratio of 1:4 by weight (1/5 Chinese tea).
In the Caribean sorrel drink is made from calyces of the roselle. In Malaysia, roselle calyces are harvested fresh to produce pro-health drink due to high contents of vitamin C and anthocyanins. In Mexico, 'agua de Jamaica' (water of roselle) is most often homemade. It is prepared by boiling the dried flowers of the Jamaica plant in water for 8 to 10 minutes (or until the water turns red), then adding sugar. It is often served chilled. The drink is one of several inexpensive beverages (aguas frescas) commonly consumed in Mexico and Central America, and they are typically made from fresh fruits, juices or extracts. In Mali and Senegal, calyces are used to prepare cold, sweet drinks popular in social events, often mixed with mint leaves, dissolved menthol candy, and/or various fruit flavors.
With the advent in the U.S. of interest in south-of-the-border cuisine, the calyces are sold in bags usually labeled "Flor de Jamaica" and have long been available in health food stores in the U.S. for making a tea that is high in vitamin C. This drink is particularly good for people who have a tendency, temporary or otherwise, toward water retention: it is a mild diuretic.
In addition to being a popular homemade drink, Jarritos, a popular brand of Mexican soft drinks, makes a Jamaica flavored carbonated beverage. Imported Jarritos can be readily found in the U.S.
China and Thailand are the largest producers and control much of the world supply. Thailand invested heavily in roselle production and their product is of superior quality, whereas China's product, with less stringent quality control practices, is less reliable and reputable. The world's best roselle comes from the Sudan, but the quantity is low and poor processing hampers quality. Mexico, Egypt, Senegal, Tanzania, Mali and Jamaica are also important suppliers but production is mostly used domestically.
In the Indian subcontinent (especially in the Ganges Delta region), roselle is cultivated for vegetable fibres. Roselle is called meśta (or meshta, the ś indicating an sh sound) in the region. Most of its fibres are locally consumed. However, the fibre (as well as cuttings or butts) from the roselle plant has great demand in various natural fibre utilizing industries.
Roselle, a tetraploid species, is a relatively new crop and industry in Malaysia. It was introduced in early 1990s and its commercial planting was first promoted in 1993. It is gradually becoming an important pro-health drink in the country. To a small extent, the calyces are also processed into sweet pickle, jelly and jam. The planted area is still small, around 150 ha annually, planted with mainly two varieties. In peninsular Malaysia, Terengganu state is the largest producer.
Genetic variation is important for plant breeders to increase its productivity. Being an introduced crop species in Malaysia, there is a limited number of germplasm accessions available for breeding. Furthermore, conventional hybridization is difficult to carry out in roselle due to its cleistogamous nature of reproduction. Because of this, a mutation breeding programme was iniated to generate new genetic variability. The use of induced mutations for its improvement was initiated in 1999, and has produced some promising breeding lines.