A member of the Camellia family, tea (Camellia sinensis) is an evergreen,
tropical plant. It has green, shiny pointed leaves and was originally indigenous to both
China and India. In its wild state, tea grows best in regions which enjoy a warm, humid
climate with a rainfall measuring at least 100 centimetres a year. Ideally, it likes deep,
light, acidic and well-drained soil. Given these conditions, tea will grow in areas from
sea-level up to altitudes as high as 2,100 metres above sea level. Tea varies in flavour
and characteristics according to the type of soil, altitude and climate conditions of the
area in which it is grown. The way it is processed also affects the flavour and
characteristic, as does the blending of different teas from different areas.
Today, tea is grown on estates or smallholdings. A smallholding is privately owned and
can be as small as 0.5 hectares or can cover several hectares. In various tea producing
countries, where tea is grown on smallholdings, co-operatives are formed to build a
tea-processing factory central to a group of smallholders. The owners of the smallholdings
sell their plucked leaf to the factory for processing.
An estate is a self contained unit, often hundreds of hectares in size, housing its own
factory, tea growing area, schools, hospital, staff houses and gardens, places of worship,
reservoir and guest house.
Under modern cultivation, tea is grown as a bush approximately one metre high, for ease
of plucking, grown from cuttings or clones. These are carefully nurtured in nursery beds
until ready for planting out. Young bushes are planted approximately 1.5 metres apart in
rows with a distance of one metre between each row. In the higher altitudes these rows
follow the contours of the hills or mountainsides to avoid soil erosion. At some of the
higher altitudes terraces are built, again to avoid soil erosion.
The bush itself is trained into a fan shape, with a flat top, called a plucking
plateau, about 1x1.5 metres in area and takes between three to five years to come to
maturity. This is dependent on the altitude at which the tea is grown. Before the first
plucking, the bushes are severely pruned by a method known as "lung" pruning.
The bushes are plucked, mostly by hand, every 7-14 days. Altitude and climatic
conditions of the growing area are the two deciding factors in this regrowth period. A tea
bush grown at sea level will replace itself more quickly once plucked, than a tea bush
growing at a higher altitude, where the air is often cooler. Only the top two leaves and a
bud are plucked from the sprigs on the plucking plateau.
The plucked leaves are collected in a basket or bag carried on the back of the plucker
and when this is full it is taken to a collection point where the plucked leaf is weighed
before being taken to the factory for processing, or "making", as tea
manufacture is known in the tea trade. If pluckers are harvesting an area near the factory
they will take their plucked leaf direct to the factory for weighing. On an estate, each
plucker is credited with their own weights of tea for subsequent payment.
A skilled plucker can gather up to between 30-35 kilogrammes of plucked leaf in a day,
sufficient to produce about 7.5 to 9 kg of processed black tea.
As black tea has the major share of the tea market in terms of production, sales and
amounts drunk, most tea factories produce black tea.
On arrival at the factory, the plucked leaf is spread on vast trays or racks, normally
placed at the top of the factory, and are left to wither (as shown below) in air at 25-30
degrees centigrade. The moisture in the leaf evaporates in the warm air leaving the leaves
flaccid. This process can take between 10 to 16 hours, depending on the wetness of the
leaf. Some factories will gently hasten the process with the aid of warm air fans.
The withered leaf is broken by machine so that the natural juices, or enzymes, are
released and on contact with the air will oxidise. This breaking is done by two methods
"Orthodox" and "Unorthodox" - terms are used to describe the machinery
used. The Orthodox machine rolls the leaf, which produces large leaf particles, known as
grades. While the "Unorthodox" term covers teas broken by either a CTC (cut,
tear and curl) or Rotovane machine. Both chop the leaf into smaller particles than those
which are produced by the Orthodox method. The smaller particles are more suited to modern
market demands for a quicker brewing finished product.
The broken leaf is laid out either on trays or in troughs in a cool, humid atmosphere
for 3-4 hours to ferment, or oxidise, and is gently turned every so often throughout the
period until all the leaves turn a golden russet colour and fermentation is complete.
After fermentation, the leaf is dried or fired. This is done by passing the broken
fermented leaf slowly through hot air chambers where all the moisture is evaporated and
the leaf turns a dark brown or black. The black tea is ejected from the hot chamber into
chests. Next it is sorted into grades, or leaf particle sizes, by being passed through a
series of wire mesh sifts of varying sizes into containers before being weighed and packed
into chests or "tea sacks" for loading onto pallets.
Factory tea-tasters will taste the finished make to ensure that no mistakes have been
made during the manufacture or that the tea has not been contaminated by anything within
the factory. Samples of the make are sent to selling brokers worldwide. All brokers will
evaluate the tea for quality and price, reporting back to the estate or co-operative, so
the tea can be sold to the best advantage.
After each "make" the tea factory is washed from top to bottom to ensure that
the completed make does not contaminate the next make of tea.
For green tea manufacture, the withered leaf is steamed and rolled before drying or
firing. This is done to prevent the veins in the leaf breaking and thus stopping any
oxidisation or fermenting of the leaf. When brewed, green tea has a very pale colour and
the wet leaf is often left whole. Green tea is drunk mainly in China, Japan and some parts
of South America. In the Western world green tea is sometimes drunk as a speciality tea.
source: The Tea Council