The coconut palm can tolerate a wide range of soil conditions. It
is particularly grown on the coastal belt on all tropical countries
where light sandy and sandy-loam soil exists which is highly permeable
and is assured with sub-soil water at a shallow depth, within easy reach
to the roots.
The physical properties of sandy soil usually suit well for coconut
cultivation, owing to its aeration and well drainage condition; even
though they are characterised by poor in organic matter, low in mineral
colloids and moisture retention capacity.
Sandy soil can support a good crop under a regular system of organic
manuring and good management. Besides coastal sandy soil, coconut palms
are grown in laterite alluvial and red sandy-soils with a pH ranging
from 5.2 to 8.0
It has been found to grow well in gravelly and laterite soils. If
laterite soil is chosen for coconut cultivation, it should be free from
rock or hard pan up to a depth of one meter or more below the surface.
These soils need good decomposing organic matter and periodical timing
to release constantly more of the 'fixing' phosphate nutrients.
It is a common practice to add one or 2 kg of common salt the bottom
of the pits, in the laterite area for softening the rocky surroundings
to aid root penetration. Increased soil aeration is gravelly areas enables
the coconut palms for wide spread root system.
However, most of the nutrients are leached away in gravelly soils
which has to be prevented by adding organic matter, neutralising the
soil acidity through amendments and protecting rich surface soils in
sloppy lands by terracing, contour bunding etc.,
The texture of the alluvial soil is very good and suits most for coconut
cultivation along the coast. It is highly porous, loose, excessively
leached and well-drained.
Clayey soil is unsuitable for coconut cultivation because of its impermeability
and indispensable drainage system. Moreover, water-logging is very common
in clayey soil which the coconut palm does not tolerate. Moreover, stagnant
wetness is injurious and hence marshy soil is unsuitable for coconut
In Karnataka, coconut growing area can be grouped in a few well-defined
Coastal sandy-soil tract of West.
Upland region between the Coast and hill slopes of South and North
Kanara with low water table;
Laterite soils of hill slopes of the West Coast with gravels and low
Sandy-loam soils with low water table in the summer.
(a) Loamy soils in the interior of Karnataka covered Tiptur, Arsikere
belt; having less rainfall (80 mm), but with a fairly good supply of
sub-soil water. (b) Red and black soils of maidan tract of Karnataka.
The coconut palm is essentially a tropical crop which grows best in
a warm humid climate.
It does not tolerate extremes of temperature and fails to come up
well in places where long dry spell and severe cold conditions prevail.
Hence its distribution is almost confide to the tropical zones such
as India, Indonesia, Malaysia, Sri Lanka, the Philippines, Pacific Islands
and West Indies, particularly in the coastal belts.
In this connection factors such as latitude, altitude, rainfall,
temperature, humidity sunshine and wind velocity require detailed consideration.
Latitude and Altitude
The coconut palm thrives well within 23° N and 23° S latitude.
Even though it is grown as far as 27° N and 27° S, those palms
put on good vegetative growth but exhibit poor nut yield and hence not
grown in a commercial scale beyond 23 °> N and 23 ° S.
Coconut is grown at different altitudes from saline seacoast to an
elevation of 1000 meters. However, it is the temperature that determines
the limits of altitude. Normally, an altitude of 600m appears to be
the limit for commercial coconut cultivation.
The coconut palm requires an equable climate which is neither very
hot nor very cold. Thus, the temperature has great influence on the
growth and productivity of the palm.
The temperature should be from 20 ° to 32 ° C, the optimum
being 27 ° C for maximum growth and nut yield.
In places where the mean temperature is less than 15 °to 20
° C, the palm does not flourish due to both physiological and morphological
changes and the cold temperature upsets the fruiting.
Coconut palm tolerates a wide range in distribution and intensity
of rainfall, ranging from 1000 to 3000 mm/year. If the precipitation
were comparatively well-distributed even a low rainfall of 1000 mm would
suffice. In well -drained soils or those soils permit free movement
of water a high precipitation of 2000 to 3000 mm can be of better advantage.
However, high precipitation with high humidity and low temperature
can upset the normal physiological functioning of the palm and also
cause water logging of the area.
Both heavy downpour during short rainy season and long dry spell are
harmful to the coconut palm. As the palm has no tap roots, it is unsuitable
to grow in a region where prolonged dry spell occurs.
Failure to receive timely seasonal rains results in the abortion of
spedices and hence adequate soil moisture should be ensured either through
percolation of water or adequate supply of irrigation.
Even in dry interior areas with a low annual rainfall of 500 to 800
mm like Tiptur and Arsikere in Karnataka, it is possible to grow coconut
where sub-soil moisture is adequate at the depression of rolling lands
and near valleys or adjacent to tanks.
Warm humid climate is good for growth of coconut palm, but the persistent
high humid conditions for a longer period reduces transpiration and
uptake of nutrients and also encourages incidence of various diseases
and pets particularly bud rot and leaf diseases. However, the monthly
means of relative humidity should not fall below 60%.
In Tall palms, wind plays an important part in the dispersal of pollen
and the fertilization of flowers; increases the evaporation of water,
leading to its greater absorption. Windy atmosphere increases transpiration
rates and helps in uptake of nutrients from the soil. If the wind is
violent or storm occurs, it is difficult to protect the palms.
The coconut palm is a sun-loving plant and light demanding, as it
requires plenty of sunshine. It tries to stand above other trees to
gain more sunlight. It does not grow well under shade. In too cloudy
weather, it fails to flower.
Lack of sunshine arrests the rate of transpiration also. About 2000
hours of length sunshine per year or 120 hours in a month are required
under normal condition for coconut cultivation below which light becomes
a limiting factor.
The leaf orientation and venation structure of coconut leaves permit
sizeable amount of solar radiation on the crown to penetrate to leaves
attached on lower levels.
The extent of this light transmission mostly varies with the number
of functional leaves on the crown and the distance at which the palms
The light incidence increases on the interspaces with the increase
in age of the palms up to 20 years and thereafter filtered light reaches
the lower profile of the canopy extending about 30% of the light incident
to the ground at about 30 years of age.
Thereafter the amount of light penetrating the canopy increases with
the age of the palms. With the increase of the height of palms, the
amount of sunlight increases from the slant rays, due to progressive
decrease in canopy coverage.
Coconut palm is mostly grown bordering the coast, getting benefit
from the humid climate throughout the year with less fluctuation of
temperature and thus having its action in regulating the climate in
a favorable way.
Nearness to the sea ensures adequate moisture, caused by the ebb and
flow of the tide, which is beneficial to the palms.
The sub-soil water supply near the coast is better than those in the
interior and is easily available at a depth of about 1 m within the
easy reach of the coconut root zone and that too fresh water, free from
salinity, even though it grows near to the sea.