Camellia sinensis var. assamica ★★★★★

Ruby 18

Also known as: Hong Yu · Hongyu · TTES No. 18 · Red Jade · Sun Moon Lake black

Cinnamon, menthol, and ripe stonefruit. Taiwan's signature wild-hybrid black tea.

Species
var. assamica
Lineage
Modern hybrid
Country
Taiwan
Year
1999
Leaf size
Large
Cup quality
5/5

Ruby 18 (紅玉, Hong Yu, "Red Jade") is Taiwan Tea Experiment Station's cultivar #18, released in 1999 after a long breeding program that crossed a Burmese big-leaf Assam line (B-729) with a selection of Taiwan's native wild mountain tea, Camellia formosensis (B-607). The cross was deliberate: TRES wanted a black-tea cultivar that married assamica body with the aromatic character of Taiwan's indigenous tea, and Ruby 18 revived the once-dormant black-tea industry around Sun Moon Lake in Nantou.

The cultivar's signature is a natural cool-mint and cinnamon-bark aroma that no other black tea reproduces — a trait traced to the wild formosensis parent. Brewed gently it gives a smooth, honeyed cup with stonefruit sweetness; pushed harder the menthol-cinnamon top note dominates. Ruby 18 is almost always sold as a single-cultivar tea rather than blended, and genuine Sun Moon Lake Ruby commands premium prices.

Modern hybrid
Deliberate cross developed by tea research institutes. Developed 1999. Parent material: Burmese big-leaf Assam (B-729), Taiwan wild mountain tea (B-607).
Lineage data & sources
Documented cross — its two parent cultivars are recorded in tea-breeding registries; trace them in the lineage explorer.
Sources: teadb.org, en.wikipedia.org

Teas produced

Black

Flavor signature

CinnamonMentholStonefruitHoneyMalt

Growing regions

Origins where Ruby 18 grows

Brands likely carrying Ruby 18

Direct-sourcing operations with focus areas that align with this cultivar's typical growing regions.

Related cultivars

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