Confusingly, Zairai is not a cultivar, but rather a term used to refer to ‘native’ or seed-grown tea plants of unknown ancestry. In China, these types of plants are called quntizhong, and in other industries they are called landraces or heirloom varietals.

Throughout most of tea’s history, tea was grown from seed, producing genetically unique plants, each with its own taste, shape, budding time, yield, and disease resistance. Today, however, most tea is grown through clonal propagation of cultivars through cutting, producing genetically identical bushes. Zairai gardens often have higher disease resistance due to their genetic diversity, but this same diversity makes them harder to harvest, resulting in significantly reduced yield and consistency, which is why most farms in Japan switched over to cultivar production in the 20th century.

However, tea produced from Zairai bushes tends to have a deeper flavour, resulting from the deep-growing roots of the older seed-grown plants, along with the natural ‘blend’ produced by these diverse plants.