Oolong tea is a diverse category of tea that spans the range of oxidation levels between green and black tea. This means that two teas labeled as “oolong” can differ significantly in aroma, flavor, and leaf shape. In fact, there are four main types of oolong tea that come from four geographically isolated regions on the eastern coast of China. Each region has its own unique terroir and specialized varieties of Camellia sinensis, and the easiest way to distinguish between the different types is by their crafting style, which can be inferred from their leaf shape.
Some oolong teas consist of compressed, or “balled” tea leaves, and are tightly compressed into small, round pebbles. This technique is common in both Anxi County, Fujian, and Taiwan and is preferred for most lightly oxidized oolongs, which remain green in color. More oxidized leaves can be rolled as well, and some rolled teas from both regions are heavily roasted, resulting in richer flavor profiles and a darker leaf. Green-style oolongs from Taiwan and China are known for their intense floral aromas, but Taiwanese teas are also noted for the creamy textures that develop at high elevations. Oolong teas from Taiwan are typically named for the mountain they are grown on, like Tung Ting, Alishan, or Lishan.
Twisted oolongs are produced in two main regions: the Phoenix Mountains in the southern province of Guangdong and the Wuyi Mountains of northern Fujian. These two styles of oolong have little in common, other than being twisted, and are distinguished by their aroma and flavor notes. Oolongs from the Phoenix Mountains are twisted and oxidized up to 30% to bring out natural fruit or flower flavors. These teas are finished with a light roast to emphasize their bright aromas and subtle flavor notes. In contrast, leaves from the Wuyi Mountains are bruised and allowed to oxidize until they are nearly 70% brown before undergoing heavy roasting, traditionally over charcoal wood. These teas have a bold and toasty flavor profile, fortified with the flavor of the roast.
While leaf shape can provide clues to the specific style of oolong tea, it alone cannot predict the flavor of the tea. Factors such as harvest date and oxidation level are more significant determinants of flavor. However, paying attention to leaf shape and other details can help identify specific styles of tea that one might enjoy and choose new teas accordingly.