Oolong Tea — The Spectrum Between Green and Black
Oolong tea production developed in Fujian Province, China, during the Ming Dynasty (1368–1644), likely from the Wu Yi Mountain area. The category's defining region shifted to Taiwan (Formosa) during the 19th century when Fujian tea farmers emigrated and established plantations in the Central Mountains. Taiwan's High Mountain oolongs (Gaoshan) developed from the 1970s as altitude cultivation expanded above 1,000 metres, producing the delicate, floral style now most associated with Taiwanese tea.
Oolong tea occupies the most complex and diverse position in the tea spectrum — partially oxidised (from 8% to 85%), producing a vast range from lightly oxidised, green-leaning oolongs (Taiwanese High Mountain Alishan, Dong Ding) with floral, milky, vegetal notes to heavily oxidised, roasted oolongs (Wuyi Rock Oolong, Da Hong Pao) with dark fruit, mineral, and toasted notes that approach black tea's intensity. This breadth makes oolong both the most challenging and rewarding tea category for exploration. Taiwanese Gaoshan (High Mountain) oolongs, grown at elevations above 1,000 metres in the Central Mountain Range, are celebrated for milk-oolong sweetness, orchid aromatics, and incredible textural smoothness. Fujian Province's Wuyi Rock Oolongs (岩茶, yancha) — growing in weathered volcanic rock — produce the 'rock taste' (yan yun) minerality found nowhere else in tea. Da Hong Pao (Big Red Robe) from Wuyi is among the world's most expensive teas.