Tea is a globally cherished beverage, enjoyed in countless forms and traditions. While many assume diverse teas, from robust black to delicate green, originate from different plants, all true teas share a singular botanical source. This common origin explains how various flavors and aromas emerge from a single plant species.
The Plant Behind All Tea
All true teas, including black, green, oolong, white, and pu-erh varieties, are derived from a single plant species: Camellia sinensis. This evergreen shrub belongs to the Theaceae family and has leathery, dark green leaves up to 13 cm long with finely toothed edges. When unpruned, Camellia sinensis can grow into a small tree, reaching 3 to 4.5 meters, though it is kept shorter in cultivation for easier harvesting.
The plant produces small, fragrant white flowers, approximately 4 cm across, with creamy white petals and golden-yellow stamens, which bloom in autumn and early winter. For tea production, the most sought-after parts are the young leaves and buds, often called the “tip and two leaves.” Camellia sinensis is native to a region spanning southern China, northern Myanmar, and the Assam region of India.
How Different Teas Emerge
The diversity in tea types stems from distinct processing methods applied to Camellia sinensis leaves after harvest. Oxidation is a factor, involving enzymes reacting with oxygen, which transforms the leaf’s color, aroma, and flavor. The level of oxidation is controlled to produce different tea categories.
Green tea undergoes minimal oxidation; its processing involves rapid heating, such as steaming or pan-firing, shortly after harvest to deactivate enzymes. This preserves the fresh, green character. White tea is also minimally processed, often just withered and dried, allowing for slight, natural oxidation. Oolong tea represents a spectrum of partial oxidation, giving it a wide array of flavors from floral to roasted.
Black tea is characterized by full oxidation, where leaves are withered, rolled to break cell walls and initiate oxidation, then allowed to fully oxidize before drying. This extensive oxidation contributes to its dark color and robust flavor.
Pu-erh tea, a unique category, undergoes a post-fermentation process, either naturally over years (sheng pu-erh) or through accelerated microbial fermentation (shou pu-erh). This fermentation, distinct from oxidation, profoundly influences its flavor and can allow the tea to improve with age.
Cultivating the Tea Plant
The cultivation of Camellia sinensis requires specific environmental conditions to thrive and produce quality tea leaves. The plant flourishes in tropical and subtropical regions, generally found between latitudes 41° N and 16° S. Ideal temperatures for growth range from 10°C to 35°C. While some varieties tolerate short periods of frost, the plant is sensitive to extreme temperatures.
Camellia sinensis prefers well-drained, acidic soils with a pH ranging from 4.5 to 6.5. Abundant and evenly distributed rainfall is important, typically between 1500 mm and 2500 mm annually. Consistent moisture is necessary for healthy leaf development and plant vigor. Altitude also plays a role, with higher elevations often leading to slower growth and more complex flavors. Major tea-producing regions worldwide meet these climatic and soil requirements.