Other producers include Argentina, Brazil, Bangladesh, Malawi, Tanzania, and Uganda. Popular variations such as English Breakfast, Irish Breakfast, Darjeeling, Ceylon, Assam, and Keemun are all black teas. The last three types are named for the regions where they are produced. This term simply denotes the size of a tea leaf, and has nothing to do with the flavor or quality of tea. The quality of black tea is determined by the origin, growing conditions, and manufacturing skill of the tea estate manager.
All tea comes from tropical or subtropical climates.
Tea plants will flourish where it is warm and where rainfall is heavy. However, while the plant grows best in hot climates, the best quality tea is made in the cooler climates at altitudes of 3,000 to 7,000 feet. The slower growth of the tea leaves at high altitudes produce more flavorful tea. Tea gardens in the Darjeeling region of India or the Uva district of Sri Lanka, for example, are more than 6,000 feet high. Many of the world's tea producing regions also may have rainy seasons and dry seasons.