Tea

White, green, yellow, pu'er, oolong and black teas all come from the tea plant, Camellia sinensis, through its two varieties, sinensis and assamica.

Variety sinensis comes from China and has smaller leaves and better cold hardiness. Variety assamica comes from Assam and grows as anything from a shrub to a large tree.

What separates the types is what happens after picking: the leaves are oxidised to different degrees, from least in green tea to most in black tea.

Withering removes excess water and starts oxidation, and tearing, rolling or bruising the leaves also triggers it. Green tea avoids oxidation, which keeps its colour and lighter character.

The plant is native to a region covering south-west China, northern Myanmar and north-east India.

Wild tea trees can grow up to 15 metres tall, though cultivated plants are often pruned to waist height.

Leaves are handpicked young, usually in spring, taking the bud or tip and the first two or three leaves. Plants are not harvested during their first three years.

A tea plant can live up to 50 years, some live for hundreds of years, and a few are claimed to be thousands of years old.

Tea is now grown successfully in more than 60 countries, including the United Kingdom.

In 1848 the Scottish plant hunter Robert Fortune smuggled tea plants and Chinese tea growers into India for the East India Company, which helped Britain establish tea estates in South Asia and East Africa.

Tea residue from a burial pit at the Han Yangling Mausoleum near Xi'an, built for Emperor Jing (188 to 141 BCE), was radiocarbon dated to roughly 2,100 years ago.

Researchers identified it as tea by three tests together: calcium phytoliths compared with modern Camellia reference material, theanine, and caffeine.

Before that study, the oldest physical evidence of tea came from the Northern Song dynasty, 960 to 1127 CE.

Tea residue from the Gurgyam Cemetery in Ngari, western Tibet, at 4,290 metres above sea level, dates to the second or third century CE, about 1,800 years ago.

Written records of tea reaching Tibet date to the Tang dynasty, in the seventh century, so the Gurgyam tea is 400 to 500 years older than those records.

World tea production, covering black, green, instant and other tea, reached 6.7 million tonnes in 2022, after growing by 3.2 percent a year over the previous decade.

China produced 3.34 million tonnes in 2022, nearly 50 percent of the world total, up from 1.92 million tonnes in 2013.

India was second with 1.37 million tonnes in 2022, a 20.5 percent share of world output.

Kenya and Sri Lanka, the two largest exporting countries, produced 542,561 tonnes and 255,973 tonnes in 2022. Sri Lanka's output fell 15.6 percent, its greatest crop shortfall since 1995.

World tea exports reached 1.84 million tonnes in 2022.

World tea consumption reached 6.5 million tonnes in 2022, growing by 3.3 percent a year over the previous decade.

China, the largest consumer, drank 3 million tonnes in 2022, 46 percent of the global total.

India consumed 1.16 million tonnes in 2022, nearly 18 percent of the total, followed by Türkiye with 250,021 tonnes and Pakistan with 247,498 tonnes.

Pakistan and the Russian Federation were the first and second largest importers of tea in 2022, and the United States was third.