Coffee cultivation

Coffee cultivation

 Introduction :

Coffee cultivated and processed in a sustainable and viable agro-ecosystem without using any synthetic chemicals is generally referred to as organic coffee. Further, it has to be certified to claim as organic. In high value plantation commodities like coffee, tea and spices there is a very good scope for switching over to organic farming. Because, many of these commodities are exported, it is possible to realise higher returns from unit quantity exported, when produced by organic means. Secondly, as these crops are generally grown in ecologically sensitive hilly tracts, adopting organic farming methods would entail not only protection of the environment but also in preventing contamination of rivers that originate from these hills. 

Selection of site :

In choosing a site for a new plantation due consideration should be given to the altitude, aspect, rainfall, exposure to wind, slope of land, sources of water and approach etc. Arabica coffee grows well at an elevation of 1000-1500 m above MSL, while robusta coffee comes up well at lower altitudes of 500 -1000 m above MSL. Locations with gentle to moderate slopes covered with a good canopy of evergreen trees are to be preferred. Southern and western aspects should be avoided especially at lower elevations. In unavoidable circumstances, such areas should be provided with more shade to protect coffee from afternoon sun. 

In wind prone areas, wind belts consisting of tall trees like silver oak, tree coffee etc. should be raised. The site selected for planting of organic coffee should be provided with appropriate isolation distance (it varies from 3-10 m) or buffer zone which is decided by the Inspector depending upon the probability of contamination from the conventional estates/ blocks, to prevent contamination with chemicals. 

Varieties :

The varieties selected for organic coffee production must be well adapted to local conditions and tolerant/resistant to pests/diseases. In case of Arabica, varieties with wider adaptability such as S.795, Sln.5-B,Sln.6 and Sln.9 may be preferred, while in case of robusta improved varieties like S.274 and CxR may be selected. 

 Raising a nursery :

Seeds for raising nursery should be collected from organic estates/ blocks only. However, if not available, seeds from conventional estates/ blocks not treated with any chemicals can be used. The organic nursery should be clearly separated from conventional nursery, if both the activities are carried out in the same estate.

 Land preparation :

Clean felling of trees is not advocated when land is prepared for planting coffee. Selective retention of evergreen trees providing filtered shade at a spacing of 9 - 12 m is desirable. The land should be divided into blocks of convenient size by laying out footpaths and roads in between. Uprooting and in situ burning should clear the ground level bushy growth. Land preparation should be completed well ahead of commencement of South - West monsoon (June).

 Soil conservation : 

The loss of top soil is negligible when the land is covered by a two tier shade canopy comprising of lower tier of temporary shade trees like dadap (Erythrina lithosperma) and top canopy of permanent shade trees. The soil erosion attains serious dimension on steep slopes without proper shade coverage. In such fields, appropriate soil conservation measures like contour planting and terracing should be practiced.

Coffee tree grows in many countries, on each continent with tropical or semitropical zones between the Tropics of Cancer and Capricorn. Robusta beans are more resistant to heat and are cultivated on flat plantations at up to 500 metres altitude. Arabica is planted at elevation of at least 2000 metres, mostly on mountain slopes where the cultivation and harvest picking are tough and meagre. Higher altitudes have a positive effect on the quality of Arabica fruits (lower temperatures and longer ripening period enhance the development of the aroma and acidic flavour) and that is the reason why special attention is paid to this. Plantations facing south give larger yield but require more fertilizers. Coffee trees often face west or north and usually grow in the shelter of shade trees or cocoa, unless cloudy skies make the shade redundant. The shade reduces the pace of soil moisture loss and maintains higher temperatures at night. Both varieties are very sensitive to frost. Coffee trees have to be protected from strong winds and extreme weather conditions common in many coffee producing countries (drought, tornado).
Coffee tree has a lot of other enemies as well. Arabica plantations have been virtually decimated by orange rust. As its name suggests, Robusta is more resilient to disease, pests and heat.
Coffee thrives on fertile, preferably volcanic soil. Coffee plant requires a thick layer of soil for its roots take up to two metres in depth in search for nutritious ingredients. A considerable quantity of humus is required for the growth of a coffee tree and can be improved by adding natural or artificial fertilizers (nitrogen, potassium, magnesium are the main fertilizers). Coffee plantations are established by using seedlings or rooted cuttings and by grafting. The most common method is planting seedlings but this method doesn’t provide maintaining the individual characteristics of the species, whereas rooted cuttings and grafting overcome this problem. The density of trees varies from 1300 to 7000 per hectare, depending on the variety and the shape. High cultivation density is possible in thick coffee shrub as in Caturra or Catimor varieties. All these aspects influence to a large extent the quality of a cup of coffee. The same botanic species produce different coffee depending on the climate, soil, cultivation manner and processing method after harvesting. 

Harvesting:

Coffee harvesting is a very delicate process and the secret of high quality coffee depends on how carefully the beans are picked. Uneven ripening, characteristic for a coffee plant, makes the harvesting complicated and a lot of effort has been made towards simplifying this process. Coffee fruits ripen at different times and this occurs not only in two neighbouring trees but in the same tree as well, in the same bunch even. Although it rarely occurs in nature that the fruits of the same tree mature at different times, coffee tree is an exception – one tree, one branch even, may produce immature (green), mature (red) and over-mature (red and black) fruits at the same time. If there are flowers present along with the fruits, the harvesting is additionally hampered.
The best way to ensure a top quality yield is manual harvesting, selecting only the mature, red fruits and picking them one at a time. Such extremely careful and precise method, called selective harvesting, is mostly applied in Columbia but also in Central America, Kenya, Ethiopia and Jamaica.
In mechanical harvesting of the crop a flexible wide-tooth comb acting as a rake is used to pick fruits from the branches. This method is financially more acceptable but the quality of the fruit is poorer. An increasingly popular method of mechanical harvesting uses shaker machines to shake the trunk, separating the fruit from the branches and making them fall off. The worst is the stripping method – fruits from all stages of development (ripe red fruits, green and yellow immature fruits and over-mature black ones) are stripped off the branch with one stroke. Leaves and all kinds of impurities fall off along with the fruits. This harvesting method may influence creating a bad aroma which becomes evident after roasting.

Planting of coffee : 

Planting of coffee seedlings should be taken up during August-September towards the end of heavy monsoon rains. At the time of planting, it is advisable to add about 50 g of rock phosphate to each pit, for encouraging root growth and better establishment of plants. In cockchafer infested fields, neem cake @ 250 g per pit is advocated. 

 After care of young plantations :

During the year of planting, the following operations help in better establishment of coffee and shade plants.After planting, the coffee seedlings should be provided with staking and mulching to protect against wind damage and to conserve soil moisture for the ensuing dry period. Towards the commencement of dry period, erecting temporary shade huts with jungle tree twigs should protect the young plants in open area.Stems of young dadap plants should be coated with lime solution to prevent sun scorching

 Planting of coffee: 

Planting of coffee seedlings should be taken up during August-September towards the end of heavy monsoon rains. At the time of planting, it is advisable to add about 50 g of rock phosphate to each pit, for encouraging root growth and better establishment of plants. In cockchafer infested fields, neem cake @ 250 g per pit is advocated. 

 After care of young plantations :

During the year of planting, the following operations help in better establishment of coffee and shade plants.After planting, the coffee seedlings should be provided with staking and mulching to protect against wind damage and to conserve soil moisture for the ensuing dry period. Towards the commencement of dry period, erecting temporary shade huts with jungle tree twigs should protect the young plants in open area.Stems of young dadap plants should be coated with lime solution to prevent sun scorching

Maintenance of new plantations: 

 Green manuring for soil enrichment : 

In newly planted fields, green manure crops like cow pea and horse gram could be cultivated for two or three years to build up soil fertility. These crops should be grown during kharif season (June-September), so as to prevent competition for soil moisture. These green manure crops contribute around 6-10 t/ha of dry matter and also effectively suppress weed growth in the early years. As most of these crops are leguminous in nature, they fix nitrogen from atmosphere. The green manure crops should be cut before flowering and incorporated into soil to improve soil fertility.

 Nutrition management :

The following practices would be essential for meeting the nutrient requirement of young coffee holdings.

• Correction of soil pH using agricultural lime or dolomite, based on soil test values, at least once in 2-3 years.
• Application of farmyard manure or compost prepared on the farm @ 500 kg/acre per year.
• Deficiency in nutrient supply can be met by using other permitted products like rock phosphate, bone meal, wood ash etc.
• Use of bio-fertilizers may also be resorted to, in a restricted manner to improve nutrient use efficiency.

Weed control:

Weeds pose a serious problem especially in new coffee clearings. Grasses need to be controlled in the initial years itself. The following measures are suggested for controlling weeds.

• In new clearings, cultural practices such as cover digging (30 cm deep) during the year of planting and scuffling (10 - 15 cm) for the next two to three years carried out during post-monsoon season, would not only bring down the weed growth but also help in conservation of soil moisture. However, in sloping terrain, avoid soil digging to prevent soil erosion. In such areas, adopt only slash weeding.
• Cultivation of green manure crops/ cover crops and mulching with weed slashings and shade tree leaf litter etc. would also help in smothering of weeds. Once the coffee bushes cover up, the weed growth would naturally get suppressed and manual slash weeding alone would be sufficient.

* Use of any kind of herbicides is strictly prohibited.

 Plant training and pruning 

The young coffee plants should be trained to provide proper shape to the bushes and to improve efficiency of operations like spraying, harvesting etc., at later stages. Generally, single stem system of training is recommended for coffee grown under shade. In this system, the plant height is restricted by topping (capping) at prescribed heights. The tall arabica varieties are topped at two stages (two-tier system) while the dwarf arabicas as well as the robustas are capped at single level (single tier system). The prescribed topping heights for different coffee varieties are:

1. Tall arabicas - 1st topping at 0.75 m. 2nd topping at 1.35 - 1.50 m (second topping is done after harvesting 4-5 crops, when the spread of lower canopy is complete)
2. Dwarf arabicas - Single topping at 0.9 – 1.5 m depending on soil fertility, wind proneness etc.
3. Robustas - Single topping at 1.35 – 1.50 m. In topping operation, the terminal portion of main stem is decapitated at the prescribed height, by providing a slant cut.