Production Technology of Tea
Botanical Name: Cornelia thea
Origin: Tea is believed to be indigenous to Assam in India only.
Area and Production:
The crop is mainly grown in Assam, and West Bengal i.e. 50% and 25% respectively Karnataka (30%) and T.N. (10%). Other minor tea growing/producing areas are located in tripura, Punjab, U.P. Himachal Pradesh, & Bihar.
The most important types in cultivation are 1. Assam and China.
It is a taller plant with soft leaves and can grow at elevations under 1500 meters.
It is dwarf bush with leathery leaves and can be grown upto 2400 meters above sea level. Many hybrids of these two are in cultivation.
1. Warm moist climate with plenty sun light.
2. Rainfall: 1500-2500 mm well distributed
Temperature: Mean ranging from 10-38°C.
3. Highelevations are good for economic life of plants and quality of leaves but total yield at high altitudes is best.
4. Frost affectsthe pfen$ adversely.
Deep liable loam and forest land rich in organic matter is very ideal. Generally tea soils of India are generally with organic matters, N, Potash, low K, lime and magnesia content hence soil Reaction is medium to strongly acidic.
Practice of liming is not followed in ease of tea because tea-does not thrive well on a soil which contains more than a trace of active lime sub soil should not be hard and Stiff and growth of tea on clay soil is more uniform and tea is of better quality than tea grown on coarse sandy soils.
Land Preparation: Cultural Method
Tea is taken on hilly areas; the land is prepared by cutting of low growing vegetation arid unwanted forest trees are cut and removed. Except few selected ones left for shade Stoop slopes are terraced and provided with contour drains and silt traps. A thick-wind-break of silver oak (Gravilica rohusta) is planted on the periphery. Also shade trees Viz. Silver oak, Jack are planted at adjoined 12-15 m apart a year in advance of the main plantation to provide protection: to provide protection against i.e. to provide shade, heat and torrential rains. They are lopped every year to provide adequate light and air.
After field / land preparation pits measuring of 30-45 em deep, 22 cm diameter, are dug at distance of 1.2 to 1.5 m from one another. Filled with mixture of surface soil + FYM leaf mould.
Raising of Seedlings:
Generally propagated by seeds; but vegetatively propagated plants give high yield, high quality, budding, grafting and layering have also been found successful.
Seeds sown first in germinating beds, then seedlings transferred- to other nurseries or baskets containing, loose friable soil. Here seedlings are allowed to grow for 6-8 months and subsequently 1.5 year (17 months) old seedlings are planted in April – May or Sept. Oct. In pits (previously prepared) dug in the permanent stags, Gapfiling as- well- as replacing, in to 30 years old bushes are also done at this time.
Fertilizers mixtures supplying 60 kg N: 30 kg. P2O5 30 K20/ha are applied in one or two doses after pruning. Nitrogenous manuring is very essential for . promotion for leaf growth. Besides this application of compost and benefit derived from leaf fall of leguminous shade trees are grown for incorporation in the soil as green manures.
The tea-gardens are hood and weeded 3 to 5 times during the rainy season. Shade trees are lopped to promote lateral development which will shade large area.
Topping and Pruning:
Tea bush is pruned regularly to maintain proper shade i.e. 1,2 to-1.5 meter diameter at 1 to L2 meter height.
When the plants are one year old-and have attained a height of 45 cm at this stage entering is done. Main stem is cut a few cm. above ground. The new laterials developed by the plant are again cut a little higher up.
This process is repeated every year. In 4 or5 years me plant becomes a mature bush of 45-60 cm height and is ready to yield a crop. To encourage lateral spread, all shoots growing through center of the bush should be removed.
After a cycle of pruning, the bush is cut back to 2-3 cm below the first cut This encourages fresh laterals and maintains yield at a high level.
In Assam pruning is done in Dec. March after allowing the bush to grow 25 cm or more.
Plucking and Processing:
Tea bush is ready for yielding after 4 to 5 years of planting and having a height of 45-60 cm. Usually plucking is restricted to 2 leaves and a bud. This is called a fine and light plucking. Coarse plucking includes extra one or two leaves. In North Tea is plucked at interval of 7-10 days from April-Dec. in South plucking continues throughout the years at weekly interval during March-May and at 10-14 days during other 3 months i.e. during June-Feb. (9 months).
For manufacturing of Black tea, the plucked leaves are dried for 18 – 24 hours in ventilated indoor racks rolled for half an hour mechanically to breakup cells, then fermented or oxidized again for 8 hours at 27°C to 105°C and passed through sieves of different moshes, thus sorting out grades and again graded into.
a) leaf : Orange peloeoe, pekoo, flowery pekoe,
b) Broken : Broken orange pekoe, broken pekoe, fanning
c) Dust tea.
The average yield is 1200-1500 kg/ha of made tea. Vegetatively propagated clones often give as much as 2000 kg/taken during cultivation and processing but on natural factors such as soil, climate, altitude and topography. Leaves are rich in caffeine and tannin.
Tea is an important foreign exchange earning crop, India exported tea worth of Rs. 340 crores during 1998 – 99. The commercial tea is either Green (Unfermented) or Black (fermented). The leaves are rich in caffeine and tannin. On infefon in boiled water, it gives a well known beverage known as tea.