,
C. liberica Bull ex Hiern)
Family - Rubiaceae
Coffee was introduced to Sri Lanka by the Arabs in 1503, and in 1658, the Dutch started its cultivation. It was a very thriving industry till the end of 19th
century covering most of the areas in which tea is now grown. The leaf disease (coffee leaf rust) ruined almost all the coffee plantations existed then. Now
there are Arabica varieties and hybrids, resistant to leaf rust, which can put back as a very profitable crop in various parts of the island where soil and
climatic factors are suitable for growing this crop. Robusta can be cultivated at lower altitudes where the temperatures are comparatively high. Generally,
coffee comes into production in 2 ½ to 3 years after planting. Under satisfactory soil and climatic conditions and good management, an average annual yield of 1,000 - 1,500 Kg/ha can be realized.
Cultivation
Agronomic Requirements for cultivation
Deep well drained fertile loam of lataritic origin with reasonable quantity of humus is good for arabica while robusta is more widely adaptable to soil
conditions. Liberica/Excelsa can thrive in poorer soils also. Coffee shows normal growth and production in soils with 5 - 6.5 pH. Liming therefore, becomes
necessary in the case of highly acidic soils.
Warm and wet conditions are conducive to growth of Robusta while Arabica requires uniform temperature and moderate rainfall.
Temperature (annual average)- 18-24 °C for Arabica, 27-29 °C for Robusta
Rainfall (annual average) - 1500-2750 mm for Arabica, 1750mm and above for Robusta
Recommended Varieties
The spices of economic importance are Coffea arabica (Arabica coffee), Coffea canephora (Robusta coffee) and Coffea liberica excela (Tree Coffee). C. arabica is more suitable to cooler high elevation regions. Though it’s grown from sea cost to 1800m above mean sea level. C. canephora is a low altitude species which thrive well under warm humid conditions and can be grown successfully up to 900m above mean sea level. C. liberica can tolerate both warm and wet conditions in soils varying from clay to peat.
Field Planting and Spacing
Coffee can be propagated by seeds, cuttings or by grafting on suitable stocks. However propagation by seeds is easy and less expensive. The following
plant spacing are recommended for monoculture.
Arabica – 1.8 m x 1.8 m (3000 plants/ha) or 1.8 m x 2.5 m (2,200 Plants/ha)
Robusta – 2.5 m x 2.5 m for single stem (1,600 plants/ha) 3 m x 3 m for multiple stem (1,100 plants/ha)
Catimore – 1.8 m x 1.8 m (3000 plants/ha)
Manuring
Coffee demands a steady supply of nutrient and this can be met by application of inorganic fertilizers in required doses
| Components |
Parts by weight |
Nutrients in the
Mixture |
| Urea (46% N) |
4 |
14 % N |
| Rock Phosphate (28% P2O5) |
5 |
11 % P2O5 |
| Muriate of Potash (60% K2O) |
3 |
14 % K2O |
| Kieserite (24% MgO) |
1 |
2% MgO |
Doses for Robusta varieties - Application rates per plant in grams
| |
Maha |
Yala |
| |
pre |
post |
pre |
post |
| 1st Year |
63 |
63 |
63 |
63 |
| 2nd Year |
250 |
- |
250 |
- |
| 3rd Year o |
350 |
- |
350 |
- |
Doses for arabica varieties and catimore - Application rates per plant in
grams
| |
Maha |
Yala |
| |
pre |
post |
pre |
post |
| 1st Year |
50 |
50 |
50 |
50 |
| 2nd Year |
150 |
- |
150 |
- |
| 3rd Year o |
200 |
- |
200 |
- |
Harvesting and Processing
It’s possible to
obtain good quality coffee, by harvesting only ripened berries and by using
proper methods of processing. Coffee can be processed by dry or wet
method. For dry method immature and infested barriers were taken. For wet
processing only ripe berries should be picked. Under-ripe or over-ripe cherries
will produce an inferior coffee. It’s generally accepted that wet method produce
better quality coffee.
Quality Requirement
Physical, chemical and sensory methods of evaluation have been applied in judging the quality in coffee. Among the above methods tasting is still the final method of judging the coffee quality. Even though it is a subjective method it has proved to be useful in practice.
The green coffee (clean coffee) is usually classified by assessing physical appearance and determining the number of imperfections and visual examination of colour, size etc. The Sri Lanka Standards Institution (SLSI) has also prescribed certain specifications mainly based on size of the beans and the percentage of triage (defectives) admissible in particular grade. The requirements for 3 grades of clean coffee beans according to the SLSI are given below.
Internal Appearance
when cut lengthwise, the internal surface should be fissured and of a dark chocolate' brown (Forestero Type) or cinnamon brown colour (criollo type).
Texture - The cotyledons should not be leathery. They should be brittle.
Beans Size - Not more than 990 dry beans per Kg for Grade I.
There are 6 grades of cocoa beans according to the specifications given by the
Sri Lanka standards Institution (SLS 106:19977)
Requirements
(Maximum %) |
Grade 1 |
Grade 2 |
Grade 3 |
| Moisture |
16.0 |
16.0 |
16.0 |
| Foreign matter |
1.0 |
2.0 |
2.0 |
| Mouldy bean |
1.5 |
4.0 |
6.0 |
| Triage |
10.0 |
25.0 |
40.0 |
All the grades should be free of dead or live insect and the abnormal odours
