As my tea bar does more direct tea buying (as opposed to buying through distributors), I have an opportunity to taste some absolutely fascinating teas. As I tasted some estate-grown Darjeelings the other day, I was reminded of how much difference the picking time makes on the character of the tea.

A “reference cup” (far left) for comparison with three Darjeelings from the same estate. The other three are a first flush (with yellow label), a second flush (green label) and an autumn pick (blue label).

The three teas on the right side of the picture above are all Darjeeling teas from the Glenburn estate. The terroir is identical. It’s the same varietal of Camellia sinensis var sinensis (the Chinese tea plant) — all FTGFOP1 clonals. They are all black teas. They were steeped for the same amount of time using the same water at the same temperature. I used the same amount of tea leaf for each cup. What’s the difference?

• The light golden tea second from left is a first-flush Darjeeling, picked on March 20th. At that time of year, the spring rains are over and the tea plants are covered with fresh young growth. The tea is very light in color, and the flavor is mild but complex with a touch of spiciness. Although all four of the teas in the picture were steeped 2-1/2 minutes, I actually prefer my first flush Darjeelings steeped for a considerably shorter time (although everyone has different opinions on that). I’m drinking a cup as I write this, and it’s just about right at a minute and a half.
• The amber cup to the right of the first-flush is a second-flush, picked in June. The drier summer climate produces a heartier cup of tea, with a flavor often described as “muscatel.” There is more body and a bit more astringency as well.
• The darkest cup of tea on the far right is called an Autumnal Darjeeling. This one was picked on November 10th. By then, the monsoons are over and the new growth on the tea plants has matured. An autumn-picked Darjeeling will be darker in color, stronger in flavor, and fuller-bodies, but without as much of the spicy notes Darjeelings are known for.

These seasonal differences account for massive differences in caffeine content as well. Early in the season, tea plants will have more caffeine concentrated in the new growth, which is what’s picked for the delicate high-end teas. The data that Kevin Gascoyne presented at World Tea Expo last year showed a 300% increase in caffeine between two pickings at different times of year in the same plantation.

Comparing Darjeeling teas can be difficult, as much of the “Darjeeling” tea on the market isn’t authentic. According to this 2007 article, the Darjeeling region produces 10,000 tonnes of tea per year, but 40,000 tonnes is sold around the world. Even if you don’t consider the local consumption, that means 3/4 of the tea sold as Darjeeling is grown somewhere else. That’s why it’s so important to buy from a trusted source.

When selecting teas, we tend to look first at the production style (black, green, white, oolong, pu-erh), and then for the origin (a Keemun black tea from China is quite different from an Assam black tea from India). As consumers, we rarely know the exact varietal of the plant or the picking season, but those factors are every bit as important to the final flavor.

I suppose the main message of this article is that you can’t judge a tea style on a single cup. You may love autumnal Darjeeling and dislike first-flush. You may enjoy a second flush from Risheehat and not the one from Singbulli.