Soil and climate conditions dramatically affect the taste of leaves from different parts of the world. The best climate conditions are usually higher in altitude with plenty of rainfall.
Cooler weather and misty mornings are preferable to allow the bush to mature more slowly. With all of these combinations, there are thousands of different teas produced from the single species, camellia sinensis.
Tea harvesting is laborious and training intensive to yield the best results. Only the bud and the second and third leaves are used. It's called "fine plucking". If more leaves are taken with the bud is called "coarse plucking" and leads to a lower quality tea. A typical tea bush will produce three thousand tea leaves a year. But these only make up about one pound of fully processed tea!