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IV. The Agronomy of Cardamom

IV. The Agronomy of Cardamom

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THE AGRONOMY AND ECONOMY OF CARDAMOM



229



highly prone to wind and drought damage, and therefore, areas liable to be

aVected by such conditions are unsuitable (Mohanchandran, 1984).



1. Temperature

Guatemalan climate oVers the ideal conditions for good cardamom growth

and productivity. Annual average temperature varies from 17 to 25 C in the

southern part and 18–23.5 C in the northern part (George, 1990). In India,

optimum growth and development are observed in the warm and humid

conditions at a temperature range of 10–35 C (Anon, 1976). The upper temperature limit will normally be around 31–35 C. In the eastern side of the

Western Ghats, a combination of desiccating winds passing from the hinter

lands of east and low humidity leads to desiccation and drying of plants. In such

areas protective irrigation would be essential for retention of humid conditions

for adequate growth, panicle initiation, and capsule setting (Korikanthimath,

1991). It is noticed that the spread of the dreaded ‘‘Katte’’ disease is more

during summer than in the monsoon season. Cold conditions result in almost

poor or no capsule setting. Hence, for healthy growth of cardamom plants,

extremes of temperature or diurnal wind are not conducive.



2.



Rainfall



In South India cardamom is grown under a range of rainfall from 1500 to

5750 mm annually. Climate of the area is determined by the annual rainfall and

the year can be divided, generally, into winter, summer, and monsoon seasons.

Cool temperature and relatively dry weather prevails from November to

February. Hot weather prevails from March to June, marked by moderate

to high temperature and occasional showers. Southwest monsoon sets in June

and continues until early September. In the more westerly areas of the hills,

rains during this period are heavy and continuous, but they decrease considerably in the eastern slopes, which experience strong winds, much cloud, and

frequent light showers. After a short gap, the northeast rains commence

and occasional rains continue up to December. This is a dry period in the

more northerly and westerly areas, but is marked by heavy rains and overcast

skies in the south and the east (Mayne, 1951b,c). In general, cardamom‐

growing areas of Karnataka State and many regions of the Idukki and Wayanad districts of Kerala State experience a dry period extending from November–December to May–June. Such a long dry period of 6–7 months is, in fact,

the principal constraint to good cardamom production.

The Indian average cardamom yield is only 149 kg haÀ1 compared to the

Guatemalan and Papua New Gunea yield of 300 kg haÀ1. Well‐distributed



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K. P. PRABHAKARAN NAIR



rainfall contributes to good yield in Guatemala (Mohanchandran, 1984). In

India, 70–80% of the total cardamom area is rainfed (Charles, 1986). Following

forest denudation in many parts of Western Ghats, normal congenial habitat

for cardamom has been adversely aVected, destabilizing the ideal cool humid

microclimate and the productivity of the crop.

Investigations on the eVect of rainfall on cardamom productivity indicate

that contribution of rainfall distribution is more important than total rainfall received and the number of rainy days. Data collected from cardamom

plantations indicate that of the 10 from 13 investigated, highest yield was

from those plantations receiving less than 2000‐mm annual rainfall. In another

survey, data from 57 locations in the Coorg district of Karnataka State

indicate that in 42 cases more than 100 kg haÀ1 dry capsule yield was obtained when the annual rainfall was less than 2000 mm. This clearly indicates

that total rainfall is not the major determinant in cardamom productivity,

and even 2000 mm of rainfall well‐distributed might suYce (Ratnam and

Korikanthimath, 1985; Subbarao and Korikanthimath, 1983). Most of the

rainfall received during June–August would result in runoV leading to severe

soil erosion, and hence, proper soil conservation measures are required to

minimize soil and land degradation. Storing of run oV water during rainy

periods in suitable farm ponds, tanks, or embankments and recycling it during

summer as protective irrigation coinciding with critical physiological stages of

the crop oVer great scope for evading total crop failure and stability of yield

(Cherian, 1977; Korikanthimath, 1987a).

In Guatemala, rainfall conditions are a lot more favorable than in India.

It varies from 2000 to 5000 mm in cardamom‐growing areas and the rainfall

is evenly distributed throughout the year. Two peaks do occur. As there are

no heat and drought stresses, as in India, cardamom yields in Guatemala

are much higher than that obtained in India, and on average stands at 300 kg

haÀ1. Similar situation occurs in PNG as well, leading to high yields (Krishna,

1968, 1997). In India, a prolonged drought in the first 6 months of the year had a

devastating eVect which led to significant crop loss especially in exposed and

partially shaded regions of Idukki district of Kerala State. India’s cardamom

production came down to the lowest level of 1600 million tonnes, which showed

an imminent need to combat recurring drought by proper soil moisture

conservation techniques, mulching, adequate shade management along with

provision for life‐saving irrigation.



C. MANAGEMENT ASPECTS

1.



Planting Systems



Following are the four principal planting systems (Mayne, 1951a).

a. Kodagu (Coorg district in Karnataka State) Malay system



THE AGRONOMY AND ECONOMY OF CARDAMOM



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b. North Kanara (North Kanara district of Karnataka State) system

c. Southern system

d. Mysore (Karnataka State) system.



2.



Kodagu Malay System



It is restricted to Coorg district in Karnataka State. Small patches of

forest land, a quarter‐one‐sixth hectare in area, are cleared and planted with

cardamom. Care is taken in selecting plots which face north or northeast to

ensure adequate lateral shade from surrounding forest trees. Seedlings from

natural regeneration are thinned out and spaces filled in, or seedlings are

raised in nurseries and transplanted in shallow pits, 1.5–2.5 m apart. The areas

are weeded periodically either using chemical weedicides or manually. The

most commonly grown variety is Malabar. After about 15 years the area is

left to natural forest cover, while the cardamom cultivation is shifted to

another patch of land. A somewhat similar system was followed by the

Madras (now Chennai in Tamil Nadu) Forest Department earlier and cardamom was collected as a minor forest produce, the areas partially cleared by

selection felling.



3. North Kanara System

This system is followed in the districts of North Kanara, Shimoga, and

parts of Chickmagalur in the State of Karnataka where cardamom is grown

as a secondary crop in arecanut gardens. Seedlings are raised in nurseries

and planted in rows, 1.5–1.8 m apart. About 1200 seedlings are planted per

hectare. Malabar is the variety usually grown. Cardamom is planted on the

margins of arecanut gardens (Areca catechu, beetel nut—a common nut used

for chewing in India and Pakistan).



4.



Southern System



This is the system most in vogue for commercial cultivation of cardamom

and accounts for about 90% of the cardamom plantations in India. Selected

areas are cleared of jungle land and all undergrowth, thinning out the

overhead shade, planting cardamom seedlings at regular distance, and cultivating according to a regular schedule. This system is adopted in the States

of Kerala, Karnataka, and Tamil Nadu. The sizes of the holdings vary

widely, but greater part of the production comes from holdings of 2–20 ha.

In most areas of Nilgiris district in Tamil Nadu, Kerala State and Tamil



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K. P. PRABHAKARAN NAIR



Nadu, the principal types of cardamom grown are varieties Mysore and

Vazhukka. In Karnataka State, Malabar is the exclusive variety grown.



5.



Mysore System



CoVee is the most popular plantation crop of Karnataka State where

cardamom is grown in isolated pockets, in ravines or in low‐lying areas of

coVee plantations. In such situations, cardamom is found either as a sole

crop in narrow strips along the ravines or as scattered clumps interspersed

with coVee plants.



D. ESTABLISHING

1.



A



CARDAMOM PLANTATION



Preparation of the Main Field



Where cardamom is cultivated on a plantation scale in virgin forest, the

first step consists of clearing all undergrowth and thinning out overhead

canopy in order to obtain an even density of shade. If the land is slopy, it

would be preferable to start clearing from top and work downwards. The

shade will have to be regulated in such a way so as to allow sunlight to filter

through tree canopy almost uniformly. The bushes, shrubs, and undergrowth are cut and heaped in rows or in piles and allowed to decay. In the

case of steep slopes, it would be preferable to utilize such debris in a manner

to assist checking any soil movement due to erosion. Contour terraces may

be formed in cases where the land is too steep. In arecanut gardens, deep

trenches, and pits are dug among palms and filled up with fresh soil brought

from neighboring forest. The ground so prepared is utilized for planting. In

marshy areas, adequate provisions should be made to drain oV excess water

by providing main and lateral drains depending on natural gradient of the

land where the plantation is being established.



2.



Spacing



Variety grown and duration of the crop determine spacing. Where it is

intended to grow on a regular replanting manner and for a limited cycle, it

is obviously desirable to plant as closely as possible, without unduly restricting the plants, so that early crops may be as large as possible. If a crop is meant

to last 10 years, with a commonly suggested crop cycle, only eight harvests are

likely to be taken and the first two at least will be dependent on the number of

plants per hectare. If, on the other hand, plantings are expected to remain in



THE AGRONOMY AND ECONOMY OF CARDAMOM



233



the field for longer periods, too close planting will lead to overcrowding and

yield reduction. This is important since cardamom clumps tend to spread

outwards as they age and gradually new shoot production will decline in the

center of the plant. It will also lead to yield reduction as the crop ages.

Korikanthimath (1983b) investigated the eVect of spacing, seedling age, and

their performance in relation to fertilizer rates and found that tiller number,

number of leaves per plant, and plant height were significantly aVected by

the diVerent treatments. Maximum tiller number (10.9 per plant) and maximum number of leaves (102.1 per plant) were seen in the case of 18‐month‐old

seedlings planted at 2 m  1 m spacing and the plants were fertilized with N, P,

and K in the ratio of 75:75:150 kg haÀ1 and a supplemental 100 kg haÀ1 neem

(Azadirachta indica) cake. In another similar investigation, where spacing and

fertilizer rates were considered, under rainfed conditions, the treatment diVerences turned out to be highly significant inasmuch as tiller number and leaf

number per plant were concerned. A spacing of 2 m  1.5 m combined with a

fertilizer schedule of 75:75:150 kg N, P, and K per hectare resulted in maximum tiller number and leaves per plant (Korikanthimath, 1982). Normal

spacing adopted in the case of the vigorous variety Mysore is 3 m  3 m, and

for the less vigorous variety Malabar 2 m  2 m spacing is adopted (Anon,

1976). In the ‘‘high‐production technology’’ field demonstration plots, primarily meant to show the farmers, spacing at 2 m  1 m on hill slopes along

the contour and spacing at 2 m  1.2 m on flat lands, gentle slopes, and valley

bottoms, yielded 500 kg dry capsules haÀ1 within 2 years from the date of

planting (Korikanthimath and Venugopal, 1989). In a spacing trial carried out

at Yercaud, in Tamil Nadu, it was observed that close spacing at 1 m  1 m

and 1.5 m  1.5 m resulted in better yield per unit area than in the case of wider

spacing at 2.5 m  2.5 m and 2 m  2 m. In slopy lands, it is advisable to make

contour terraces in advance of the planting date and pits may be dug along

the contour for planting. Depending on the slope, a distance of 4–6 m may

be provided along the slope between the contour lines. Close planting may be

adopted along the contour.



3.



Methods of Planting



The factors which determine the planting systems are the land, soil fertility,

and the probable period over which the plantation is expected to last. Seedlings are planted in holes in some places, which are scooped out at the time

of planting. In other areas, considerable care is taken in preparing pits

for planting. Spots where pits are to be dug are marked with stakes, soil

dug out from the pits, and they are filled with surface soil mixed with leaf

mould, compost, or cattle manure (Subbaiah, 1940). Commonly pit size is

60 cm  60 cm  45 cm. Some plantations use pit size of 90 cm  90 cm Â



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IV. The Agronomy of Cardamom

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