Uses
The plant is considered to have antihypertensive properties. Primarily, the plant is cultivated for the production for bast fibre from the stem of the plant. The fibre may be used as a substitute for jute in making burlap. Hibiscus, specifically Roselle, has been used in folk medicine as a diuretic, mild laxative, and treatment for cardiac and nerve diseases and cancer.
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.
Tea
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).
Hibiscus flowers are commonly found in commercial herbal teas, especially teas advertised as berry-flavoured, as they give a bright red colouring to the drink.
A roselle drink
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. A similar thing is done in Jamaica but additional flavor is added by using ginger and rum, it is a popular drink of the country at Christmas time. In Mali,Senegal, The Gambia, Burkina Faso and Benin 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.
Medicinal uses
Many parts of the plant are also claimed to have various medicinal values. They have been used for such purposes ranging from Mexico through Africa and India to Thailand. Roselle is associated with traditional medicine and is reported to be used as treatment for several diseases such as hypertension and urinary tract infections.