Everything you need to learn about coconut cultivation, harvest and growth.
Introduction to Coconut:
Coconut is a perennial palm, which is grown extensively in many islands and in humid coastal areas of the tropical countries. It is not found far off from the sea. It is probably a native of the western parts of tropical America or the ancient land of Papua. According to De Candolle, the introduction of coconut into India, Sri Lanka and China took place not more than 3,000 years ago.
So far as India is concerned, coconut is chiefly cultivated in Kerala, Tamil Nadu, Karnataka, Andhra Pradesh, Maharashtra, Orissa and West Bengal. The country grows the crop in about 14, 30,000 million hectares and produces roughly 7,563 million nuts annually. India ranks second in the world in respect of coconut production.
The coconut plant is known as the Kalpa Vriksha, presumably because it provides not only food and shelter, but many other necessities of life. No other tropical palm is as important economically as the coconut, which is mainly cultivated for the nuts. Two very valuable products are obtained from the nuts, namely the copra that yields oil, and the fibre.
Coconut (Cocos nucifera L.) belongs to the family Palmae. The plant is perennial, tall and erect with an unbranched trunk attaining a height of about 25 m and with a crown of long, feathery leaves. Leaves are pinnate, long; leaflets are equidistant, about one metre in length, linear- lanceolate. Inflorescence is a long and branched spadix. Flowers are small and unisexual. Perianth segments leathery and valvate.
Stamens 6 are filaments short, anthers linear. Carpels 3, connate in a 3 – celled superior ovary; ovule is solitary, basal. Style is short. Stigmas 3 are recurved. Fruit is a large fibrous drupe, 20-30 cm long, ovoid, 1-seeded, with a thick fibrous pericarp and hard endocarp; the fleshy endosperm lines the endocarp and the central portion is filled with a fluid. The crop is cross-pollinated.
Climate and Soil Required for Coconut Cultivation:
A humid and warm climate with a well-distributed annual rainfall of 100 to 225 cm is quite suitable for the plant. It thrives best in equable climate, neither very hot nor very cold. Although the plant is grown mainly in the coastal plains, it can grow at elevations of 600 to 900 m above the sea-level, if the temperature is favourable, as in the case of areas near the Equator.
Long spells of drought and also of cold are unsuitable for the plant, which grows and yields best when the mean annual temperature is about 27°C and the diurnal variation is 6° to 7°C. The growth and the yield of the plant are adversely affected by frost and low humidity.
The plant does quite well in almost all types of well-drained tropical soils. Coastal sand, red loam, laterite, alluvial and reclaimed soil of marshy low land are suitable for growing coconut.
Cultivation of Coconut:
Coconut can be propagated only through seeds. The selection of the planting material is very important. Full-sized, well-filled nuts from healthy, high-yielding and regular bearing mother-palms have to be selected for propagation. The proportion of female flowers, the setting percentage, and the content of copra (dried kernel) are other important characteristics to be taken into consideration at the time of selection of the mother-palm. A careful selection of the seedlings at the time of transplantation is also equally important. The seedlings should be quite healthy and should possess a minimum of six leaves when they are one year old.
Selected nuts are planted at the beginning of the monsoon, in a nursery in rows running 38 cm apart, the plant to plant distance in a row being 30 cm. The seedlings are ready for transplantation in the orchard when they are 9-10 months old.
The land for the orchard is cleared and levelled before pits are made for transplanting seedlings. The depth of the pit varies with the type of the soil. In the case of a sandy-loam orchard with a low water-table, pits measuring 1 m × 1 m × 1 m are generally considered suitable, while for laterite soils with a rocky substratum, pits of the size of 1.2 m × 1.2 m × 1.2 m are good.
At the time of planting, the pits are filled with loose soil and a final depth of about 60 cm is left. In general, a spacing of 7.5 m to 9 m is adopted. This can accommodate 177 to 124 plants per hectare in the square system of planting. In the triangular system of planting, another 20 to 25 plants per hectare can be accommodated.
In soils with good drainage, seedlings can be transplanted at the beginning of the southwesterly monsoon. In case irrigation facilities are available, planting should be undertaken at least a month before the beginning of the monsoon. In low-lying areas, however, which are flooded during the rains, seedlings should be transplanted after the monsoon.
It is necessary to take sufficient care of the seedlings for the first few years, in their early stages of growth. During the summer, the seedlings should be properly shaded and regularly irrigated. The pits should be cleared of all weeds periodically. It is also necessary to examine the palms frequently for the attack of insects and fungus diseases, if any, and prompt remedial measures should be adopted.
The coconut palm generally starts bearing at the age of 5 to 7 years and its yield gets stabilized from the tenth year onwards. The palm continues to give more or less similar yields for 50 to 60 years. It is necessary to undertake regular inter-cultural operations and manuring for obtaining high yields of the palms.
Manuring and Fertilization:
The dose of fertilizers recommended for ordinary tall varieties is 500 g of N, 300 g of P2O5 and 1,200 g of K2O per palm in a year. A much higher dose is required for hybrids and varieties with high yield potential and the same is 1,000 g of N, 500 g of P2O5 and 2,000 g of K2O.
If the soil is deficient in organic matter, 50 kg of green manure or compost should be applied to each palm. Cowpea, sunnhemp and Calopogonium mucunoides are some of the plants used for green manuring. Fertilizers may preferably be applied in two split doses. One-third of the dose is spread around the tree within a radius of 1.8 m and incorporated in the soil after the summer showers are received.
The remaining quantity may be spread over the green-leaf manure or compost in the beginning of September. Under conditions of assured supply of water throughout the year, the fertilizers may be applied in four split doses at intervals of three months.
It has been seen that under rain-fed conditions, various tuber-crops, like tapioca, yams, sweet potato, ginger and turmeric, besides banana, pineapple, upland rice and pulses can be successfully grown as intercrops in adult coconut plantations without any harmful effect on the palms.
Harvesting and Yield:
After the coconut palm attains the normal bearing stage, a bunch of nuts is produced in every leaf axil at almost regular intervals of a month throughout the year. Production continues during the entire period of life of the plant extending over 50 or 60 years. The nuts take about a year to mature after fertilization. Harvesting is usually done once in 45 or 60 days. Nuts for ‘ball’ copra are harvested at the dead ripe stage.
For culinary purposes and for making ‘cup’ copra, nuts are generally harvested when they are 11 months old. Tender nuts are in great demand in certain states for the delicious soft drink obtained from them and they are harvested at the age of 6 to 7 months. The average yield of nuts per hectare ranges from 10,000 to 14,000 per annum. A well-maintained garden can yield double this number, roughly about 25,000 nuts per hectare.
Preparation of Copra and Extraction of Oil:
The dried kernel of the nut known as copra is the main product obtained from coconut. The fully matured nuts are stored un- husked for about a year to make them completely dry, after which they are husked and split into two halves. They are then dried in the sun for a couple of days. As a result of this drying, which may be done by artificial heat also, the kernel or copra gets detached from the shell.
Further drying of the copra is done for a few days. The copra thus obtained is known as ‘cup’ copra. Preparation of ‘ball’ copra is done by storing fully ripe unhusked nuts for about 8 to 12 months on a raised platform in a shed. They have some time to be smoked or slowly heated with a fire so as to quicken the process of drying.
The water inside the nuts dries up and the kernel gets detached from the shell. The nuts are carefully broken after husking. The ‘ball’ copra, which is obtained by this method, is clean and sweet and is regarded as a very valuable product. The oil is extracted from the ground copra by cold expression. The content of the oil, which is light-yellow in colour or colourless, ranges from 65-70%.
Uses of Coconut:
Refined coconut oil is in great demand for edible purpose and is commonly used in certain states as a cooking medium. It is also used as hair-oil and for making margarine and vegetable ghee. Further, good-quality soaps, cosmetics, shaving creams, shampoos, etc. are prepared with the oil.
The cake left after the extraction of oil is largely used as a feed for cattle and poultry. The tender nuts are in demand for their liquid, which is a delicious and refreshing drink. This liquid is said to have certain medicinal properties. The shell of coconuts is used as a fuel and for production of charcoal, and also for making different curios.
The coconut fibre known as coir, which is extracted from the husk, is spun into coir yarn, which is either used as such or made into ropes, mats, nets, bags, etc. The dry leaves of coconut palm are commonly used for thatching houses and for temporary sheds in Kerala and in some other states in the south.
The trunk of the mature palm serves as timber for constructing houses. The coconut inflorescences are tapped for extracting juice, which may be converted into sweet or fermented toddy. Sweet toddy can be used for making jaggery and sugar and fermented toddy, which is a mild alcoholic drink, for vinegar.
Varieties of Coconut:
Two distinct groups into which coconut palms are broadly divided are the tall and the dwarf. Hybrids, tall × dwarf and dwarf × tall are early bearers and better than their parents in yielding ability under favourable conditions. Certain indigenous and exotic types have also been found to be high-yielding.
A few of them, namely, West Coast Tall (WCT), Laccadive Ordinary (Chandra Kalpa), Laccadive Micro (LM), East Coast Tall (ECT) and Banawali Green Round (BGR), all of which are tall, and Chowghat Orange Dwarf (COD), Chowghat Green Dwarf (CGD), Malayan Green Dwarf (MGD), Malayan Yellow Dwarf (MYD) and Gangabondam (GB), all of which are dwarf, are quite popular with coconut growers.
Among the hybrids developed, Chandra Sankara (COD × WCT), a Dwarf × Tall combination, Chandra Laksha (LO × COD), Laksha Ganga (LO × GB), VHC – 1 (ECT × CGD) and VHC – 2 (ECT × MYD), all Tall × Dwarf combinations, have been found quite promising.
Diseases of Coconut:
Some of the common diseases of coconut are:
(i) Bud rot, fruit rot and nut fall caused by Phytophthora palmivora, which can be controlled by spraying 1% Bordeaux mixture on the plants, specially the bunches before the monsoon.
(ii) Root rot caused by Ganoderma lucidum, which can be controlled by felling the diseased palms, digging them out and burning them and also spreading 1 to 1.3 kg of sulphur and incorporating it into the soil.
(iii) Leaf rot caused by Helminthosporium halodes, which can be controlled by spraying the crown with 1% Bordeaux mixture.
(iv) Stem bleeding caused by Ceratostomella paradoxa, which can be controlled by cutting out discoloured tissues and painting the cut surfaces with hot coal-tar or Bordeaux paint.
(v) Grey leaf caused by Pestalotia palmarum, which can be controlled by resorting to better cultivation and judicious manuring.
(vi) Wilt disease caused probably by a bacterium and a virus, for which no control measure is yet known.
Insect Pests of Coconut:
Some of the common insect pests of coconut are:
(i) Rhinoceros beetle (Oryctes rhinoceros), which can be controlled by burning all decaying refuse, spraying 0.1% BHC on breeding (manure) pits, filling the leaf axils with 5% BHC or Chlordane dust mixed with sand (1 : 1).
(ii) Cockchafer beetle (Leucopholis coneophora), which can be controlled by deep ploughing during March-May, coupled with a soil application of 5% Aldrin or Chlordane.
(iii) Coconut bug (Stapanitis typicus), which can be controlled by spraying 0.1% BHC + 0.1% DDT.
(iv) Red palm weevil (Rhynchophorus ferrugineus), which can be controlled by destroying the attacked palms as well as the dying and dead palms and by closing the holes made by the weevils after injecting 0.002% Pyrethrins or petrol into them and also filling the leaf axils with 5% BHC and sand (1 : 1).
(v) Black-headed caterpillar (Nephantis serinopa), which can be controlled by cutting and destroying infested fronds and spraying 0.1% BHC + 0.1% DDT.
(vi) Termites (Odontotermes obesus), which can be controlled by treating the soil with 5% Aldrin dust just before sowing and transplanting.