Sebastian spent time in Darjeeling in 2002, talking with many growers and tasting teas. He was there just at the end of the First Flush season and the beginning of the little known Banjhi period. Here are his notes on the his trip.
Tea is one of the only plants that is used only for the vegetative growth, not its fruit or flower. The tea plant is an evergreen small tree by habit, but has been trained as a shrub/bush through the periodic management practices like plucking and pruning.
After the winter dormancy the new growth is highly prized as the first tea of the season. Depending on the region it may become white tea or green tea. In Darjeeling it becomes its famous First Flush tea. After the first spurt of growth from the plant it goes into a second period of dormancy. This occurs about a month after first flush starts and is called the Banjhi period. The plant produces a small bud, which doesn't grow to full size, as well as a leathery larger leaf which has little taste and is hard to process.
During this two-week period the plant must be plucked to get rid of these leaves. Often teas are made from these leaves, but the result is a low-quality tea, often produced for local consumption. The Banjhi plucking allows the plant to grow the small and extremely desirable Second Flush leaves.
Travel Diary, Darjeeling 2002