I found this article which tells the differences between the flushes for Darjeeling tea.
http://india.blogs.nytimes.com/2012/12/ ... ushe/?_r=0
[quote=Jim Yardley NY Times]Anil K. Jha, superintendent of the Sungma Tea Estate, one of the oldest tea estates in Darjeeling, explained to me that tea is governed by four basic seasons, known as “flushes.”
The First Flush begins around late February and ends in late April or early May. Workers combing through tea bushes are looking for the small green leaves, usually two to a stem with a bud, or conical shoot, in the middle. The leaves the First Flush produces are yellower in color than those that follow and more delicate in taste. For years, Germany has been a major importer of First Flush teas from Darjeeling, and prices are often the highest of the year during this season.
The Second Flush runs from early June through the middle of July. These teas are more amber in color and have a fuller taste. Mr. Jha said the Second Flush teas are also more expensive. Japan is a regular importer of Second Flush tea, and many Americans also prefer it, he said.
Then comes the Monsoon Flush, which runs during the rainy season from the middle of July through the end of September. These teas are considered of lesser quality compared with those harvested in the other seasons in Darjeeling, because the plants are absorbing lots of water.
Finally comes the Autumn Flush, from early October through early December. The taste is closer to the Second Flush, with a more floral aroma and a full body.
Tea plucking shuts down from December to March in Darjeeling.
Tea bushes can live for well over 100 years, though production declines over time. Growers are now cloning plants so that they can keep the Darjeeling taste alive as the older plants die off.[/quote]