Tea comes from one species, Camellia sinensis. Within it, two widely cultivated varieties give us a useful botanical orientation: Camellia sinensis var. sinensis, often called the China type, and Camellia sinensis var. assamica, often called the Assam type.
They are varieties rather than separate tea species. Both can be made into many tea classes. The plant offers the material, and the maker's decisions shape the finished tea.
The small-leaf China variety
The China variety is generally a many-stemmed bush with smaller leaves. It is associated with eastern and south-eastern China and with warm-temperate to subtropical growing regions. Horticultural sources also describe it as more tolerant of cold than the Assam variety.
Its compact growth habit and smaller leaf are broad botanical tendencies. Gardens contain many cultivars, and generations of selection have produced great variation within the variety.
The large-leaf Assam variety
The Assam variety tends towards a taller, more tree-like habit and larger leaves. Its native range belongs to a warm arc extending from Yunnan in south-west China through northern Myanmar to Assam in north-east India and across parts of mainland South-East Asia.
That range matters because the name Assam can otherwise sound as if the plant belongs to a single modern region. The botanical and genetic picture is wider. Cultivation and trade have also moved tea plants far beyond their earlier ranges.
A long separation
Genomic modelling places the divergence of the China and Assam varieties somewhere between roughly 0.4 and 1.5 million years ago. This is an estimate with a wide interval, yet it makes one point clear: the varieties separated long before human tea cultivation.
Research into domestication adds another layer. Population genetics identifies multiple cultivated lineages, including China-type tea, Chinese Assam-type tea and Indian Assam-type tea. Tea entered cultivation through more than one human relationship with the plant.
These findings are still refined as researchers sample more wild and cultivated populations. They are best read as a developing botanical history rather than a single origin story.
Variety is only the beginning
Leaf size and growth habit help distinguish the plants in broad terms. They do not dictate one flavour, one tea class or one way of preparation. Cultivar, altitude, soil, weather, season, plucking standard and processing all shape what reaches the bowl.
A China-type cultivar can become green, white, oolong or red tea. Assam-type leaf can also move through different forms. Hybrids and locally selected cultivars further soften any neat division.
Reading variety in practice
A variety name is most useful when it sits beside other exact information. The cultivar narrows the plant material. The garden and altitude place it. The harvest gives it a season. The processing record shows what the maker chose to do with the leaf.
At the tea table, the finished leaf rarely offers a simple visual proof of variety. Rolling, cutting, roasting and compression can obscure the original form. Even an open infused leaf must be read carefully because cultivar selection and hybridisation create forms between the broad small-leaf and large-leaf tendencies.
This is why the variety never stands as a shortcut to quality. A broad botanical tendency cannot rank one garden over another or promise a particular cup. The name belongs within a chain of evidence, from plant and place to harvest and making.
The two-variety distinction remains valuable because it gives tea a botanical depth. It shows one species carrying old divergence, several domestication histories and many cultivated forms. It also keeps modern national labels from collapsing a native range that crosses present borders.
The useful distinction is botanical: one species, two widely cultivated varieties, different growth tendencies and overlapping human histories. From there, the maker and the place take over.
When a tea names its cultivar or variety, receive that information as the first layer of the leaf's identity. Then look for its garden, harvest and method of making. A plant name opens the story. It never finishes it.