Question

Describe the temperature and rainfall conditions suitable for tea cultivation in India?

Answer 1

Hint: In India, tea grown in sixteen states: West Bengal, Assam, Kerala, and Tamil Nadu account for about 95 percent of the total production. Tea gardens are set up on cleared hill slopes where trees are planted for shade in advance.

Complete answer:
Tea cultivation requires a moderately humid and hot climate. Climate influences crop distribution, yield, and quality. Therefore, before cultivating tea in a new place, the suitability of the climate has to be considered initially. On well-drained fertile acid soil on highlands tea grows best.
Rainfall: In North-East India the average annual rainfall ranges from 2000 to 4000 mm. However, more than the total amount, the distribution of rainfall matters for a sustained high yield of tea throughout the season. In North-East India, rainfall distribution is not regular. The excess rainfall during the monsoon months of June to September results from drainage problems. The average monthly rainfall during the period from November to March is less than evapo-transpiration loss and the resulting soil moisture deficit also affects tea bushes. If this dry spell persists longer, tea plants suffer heavily and the crop goes down in spite of having sufficient rainfall during monsoons. Thus, adequate rainfall during the winter and early spring season are crucial for high yield.
Temperature:
Temperature affects the yield of tea by influencing the rate of photosynthesis and controlling dormancy and growth. In general, the ambient temperature within 13 degrees Celsius and 28 to 32 degrees Celsius are conducive for the growth of tea. Maximum ambient temperature above 32 degrees Celsius is unfavorable for optimum photosynthesis more if it is accompanied by low humidity. In the tea belts of this region, the average winter minimum temperature remains less than 12 degrees Celsius and there is hardly any tea growth during this period. Flushing commences from the month of March with the rise in temperature. Winter dormancy however is the result of the interaction of low temperature and short day length. Low-temperature results in low yield and slower growth in the hill district of Darjeeling compared to the plains of Assam and Dooars. A high RH and humid climate favor the growth of tea.

Note: Day Length and nature of soil are the other two factors affecting tea cultivation. Day length influences dormancy and growth in tea bushes. When days with a duration less than 11hr 15 min last for a minimum of six weeks tea bushes become dormant. Tea grows well on soils with acidic pH in the range 4.5 to 5.5, well-drained soils having a good depth, and more than 2 percentage organic matter. Shallow and compacted sub-soils limit root growth.