The tea plant belongs to the genus Camellia, as do the species of Camellia commonly found in gardens. Black tea is produced primarily from the plant Camellia sinensis var. assamica, which is native to the Assam region of India, and its harvested leaves are fermented and dried, resulting in a brown leaf.
Green tea is produced mostly from Camellia sinensis var. sinensis, native to China, and its harvested leaves are steamed or roasted to prevent fermentation and then dried, resulting, in a green leaf.
Oolong tea is also produced from Camellia sinensis var. sinensis but the harvested leaves are only partially fermented before drying.
While three main types of tea are recognised, globally there are many geographical variations of the main tea plant varieties, and many cultural variations on procedures to make tea.
Global production of tea, averaged over three years to 2016, was 7.9 million tonnes. While there are no figures available on production of different types, general industry estimates are that 72% is black tea, 25% is green and 3% is oolong.
In Australia, black tea is produced in northern Australia from plants descended from several sources of seed, most likely Camellia sinensis var. assamica. Existing plantings are based on suitable provenance stock rather than specific varieties. Japanese green tea is grown in the southern half of Australia from specific Japanese varieties of Camellia sinensis var. sinensis. These varieties are a smaller and slower growing plant, with smaller leaves and more cold tolerance than ‘black tea’ varieties. Green tea varieties require a dormant period during winter to produce the important first flush of growth in mid to late spring, and the plants have three to four flushes of active shoot growth per year.
Consumption of green tea is growing around the world, as the health benefits of the drink are discovered and promoted. The production of Japanese green tea in Australia is a small niche industry, with nearly all growers in north east Victoria supplying a Japanese beverage company that has established itself in the growing region. In New South Wales, a Japanese company has established a farm and processing facility on the New South Wales central coast, to supply the Japanese market.
Facts and figures
- Tea is the second most consumed drink in the world after water, with an estimated 18–20 billion cups of tea consumed every day
- Green tea plants can be harvested 3–5 times a season
- Proximity to a processing facility is essential for tea production
- Green tea originated in south west China and has been used as a beverage and medicine in China since 2700 BC
- Britain imported green tea from China for over 200 years but in the 1830s native tea plants were discovered in the British colony of India and the British have controlled the world marketing of black tea since
There are two main processors of green tea. One in Victoria that contracts 11 growers in the region, and one in New South Wales where there is one tea plantation, which is owned by the company that has also developed a processing plant in the same area.
Commercial plantings of green tea in Australia total less than 80 hectares and production in 2011–12 was 1,300 tonnes of wet green leaf. In the longer-term, both processors are hopeful of increasing production. Trial or small plantings also exist in Tasmania, Western Australia and Queensland.