Sun Moon Lake Black Tea: Taiwan's Ruby Red
Around Sun Moon Lake in Nantou, Taiwan makes distinctive black teas — above all Ruby Red (Tai Cha No. 18), with its signature mint-and-malt character.
By David Wu · Updated June 1, 2026 · 6 min read
A black tea worth the trip
Taiwan is famous for oolong, but its black teas — centered on Sun Moon Lake in Nantou — are a genuine specialty, not an afterthought. The lake's warm, humid microclimate is ideal for the leaf.
Ruby Red (Tai Cha No. 18)
The star is Ruby Red, also called Tai Cha No. 18, a cultivar bred from native Taiwanese wild tea and Burmese Assam. Its signature is a cooling, menthol-like aroma riding over malt and honey — instantly recognizable and unlike Indian or Sri Lankan black teas.
Other local teas
You will also find straightforward Assam black tea and the floral, aromatic Tai Cha No. 21 (Hong Yun). Together they make Yuchi and the lakeshore a small but distinctive black-tea region.
How it tastes
Smooth and naturally sweet, with malt, gentle honey, and that cooling top note. Bitterness is low, which is why it shines without milk or sugar.
How to brew it
It is forgiving. Brew it Western style (one longer steep) for an easy cup, or gongfu style for more nuance. Use near-boiling water; it tolerates a slightly longer steep than a delicate oolong.
Who it's for
Black-tea drinkers looking for something distinctive, and anyone who wants a smooth, low-bitterness tea to enjoy plain. Pair a visit with the scenery of Sun Moon Lake itself.
Frequently Asked Questions
- What is Ruby Red tea?
- Ruby Red, or Tai Cha No. 18, is a black-tea cultivar bred in Taiwan by crossing native Taiwanese wild tea with Burmese Assam. It is known for a distinctive cooling, menthol-like aroma over malty sweetness.
- Where is Sun Moon Lake tea grown?
- Around Sun Moon Lake and Yuchi Township in Nantou, central Taiwan. The lake's warmth and humidity suit black-tea production.
- Should I add milk to Sun Moon Lake black tea?
- Most enthusiasts drink it plain to enjoy its natural sweetness and aroma. It is smooth and low in bitterness, so milk is usually unnecessary.
- Is it different from Indian or Sri Lankan black tea?
- Yes. Although it shares Assam ancestry, the Taiwanese terroir and the No. 18 cultivar give a softer body and a signature cooling, almost minty top note that sets it apart.