SMALL CARDAMOM CULTIVATION IN INDIA
Botanical name of small cardamom is Elettaria cardamomum. It is popularly known as queen of spices. Small cardamom, which is used as spice, is in fact a dried fruit of a tall perennial herbaceous plant. India is a major producer, consumer and exporter of small cardamom. In India, small cardamom is mainly cultivated in Kerala (60%), Karnataka (30%) and Tamil Nadu (10%). Small cardamom is one of the most expensive spices in the world.
Plants of small cardamom are naturally seen in the hilly tracts of the Western Ghats. Since the areas in and around the Western Ghats are most suitable for its growth, commercial cultivation of small cardamom is mainly concentrated in this region. Small cardamom is abundantly grown in areas receiving annual rainfall of 1,500–4,000mm and temperature of 10°–35°C. Optimum altitude favored by the plants is 600–1,500m above mean sea level.
Small Cardamom is generally grown in virgin forest soils rich in organic matter. Loamy soils rich in humus are best suited for commercial cultivation of small cardamom. Slightly acidic soils with an ideal pH of 5.0–6.5 are best for the growth of these plants.
Commercially cultivated varieties of small cardamom are Mudigere 1, PV 1, CCS 1 and SKP 14 (for Karnataka) and ICRI 1 and ICRI 2 for Kerala and Tamil Nadu.
Both seed propagation and vegetative propagation are practiced in small cardamom. Vegetative propagation is favored over seed propagation as the latter ensures large scale commercial production of true-to-type planting materials of high-yielding lines. The suckers free from pests and diseases are generally used for vegetative propagation. Micropropagation using tissue culture technique is also practiced for commercial propagation. As in case of suckers, tissue-cultured plantlets also behave like that of the parents ensuring high productivity, if original tissue is selected from high-yielding lines. Seedlings are raised in nursery beds and they become ready for planting in the main field within 10 -18 months.
Land is prepared by adding sufficient organic matter and clearing all under-growth. Pits of 45cm × 45cm × 30cm size may be dug in April–May and filled with a mixture of top soil and compost or well-rotten farmyard manure. If land is sloppy, contour terraces may be made and pits may be taken along the contour. Recommended spacing for contour planting is 2m × 1m while for Malabar type, recommended spacing is 2m × 2m between plants and rows in Karnataka. A spacing of 2–3m from plant-to-plant and row-to-row is adopted in Kerala.
Ideal time for planting cardamom is at the onset of South – West monsoons (June – July). Cloudy days with light drizzles are ideal for planting. While planting suckers, one mature sucker along with a young growing shoot is planted in a pit. After planting, pits are filled and base is covered with mulch. While planting seedlings, care is taken to avoid deep planting. Seedlings are planted up to collar region in the pit. The seedlings should be supported by stakes and mulched. In case of tissue culture seedlings, hardened plants are planted in the main field.
Recommended fertilizer dose is 75:75:150kg NPK/ha. Application of lime corrects soil acidity and enhances rate of nitrification, resulting in better growth. A fertilizer dose of 120:120:240kg NPK/ha to the high-density planting of (5,000 plants/ha) is recommended for Karnataka, whereas a dose of 30:60:30kg NPK/ha is recommended in Kerala. Organic manures like compost or cattle manure may be given @ 5kg/clump. Neem-oil cake may be applied @ 1kg/clump. For split application of fertilizer, May and September is optimum time. Under rainfed condition, fertilizer should be applied in 2 splits. The first application helps in production of suckers and development of capsules, whereas the second helps in initiation of panicles and suckers. In irrigated plantation, application of fertilizer in 4 split doses at a quarterly interval is beneficial. Fertilizer should not be applied during heavy showers.
Before application of fertilizer, panicles should be coiled encircling the base of the plant. Fertilizer may be applied around the plant in a circular fashion and incorporated in the soil with a hand fork. Mulching should be done immediately after incorporating the fertilizer. The panicles may then be released and spread on mulch to facilitate movement of honey bees for effective pollination and better setting of capsules.
Frequent weeding is necessary (2–3 rounds of weeding in May–June, August–September and December–January). Plant base should be mulched regularly. Shade of the plants should be regulated as and when necessary. Exposing the panicles over the mulch is beneficial for bee pollination. Trashing may be carried out to remove old and drying shoots of plants. It should be done once in a year with the onset of monsoon under rainfed conditions and 2–3 times in high-density plantations provided with irrigation facilities.
Well ahead of planting, suitable fast-growing shade trees like cedar, balangi and elangi should be planted in the main field. To provide adequate light during monsoon, shade regulation may be taken up in May before the onset of the monsoon. Two-tier canopy is desirable with a height not more than 3m between the lower and higher canopy. Areas exposed to western side should have adequate shade. A thin layer of fresh fertile soil rich in organic matter may be provided at the base of the clump, covering up to the collar region by scraping between the rows or collecting soil from staggered trenches/check pits. Care must be taken not to heap the soil above collar region of the clump lest it tilts up the plant in course of time.
Frequent irrigation at 10–15 days intervals is necessary during the summer months. Regular irrigation (25mm–37.5mm/irrigation) helps in initiation of panicles, flowering and fruit set. The soil moisture level should always be maintained above 45–50%. Overhead irrigation method is ideally-suited to cardamom plantations. Drip irrigation may also be practiced. The flow of water through the drippers are so adjusted that 2–3 liters of water is discharged/hr. Application of 10–15 liters of water/plant/day is sufficient for cardamom.
Harvesting and Postharvest management
Plants start bearing in the second or third year of planting. The fruits mature at 30–40 days intervals, necessitating 5–6 pickings. Harvesting season is October– November. In Kerala and Tamil Nadu, harvesting starts from August–September and continues till February–March, whereas in Karnataka, it starts in July–August and continues up to December–January. Capsules are harvested just short of full ripeness. Over mature fruits split on drying floor, whereas the unripe fruits shrivel on drying. An average yield of dry capsules from a well-maintained plantation comes to 400 - 500kg/ha.
Drying of Capsules
Both sun drying and machine drying are practiced. After harvesting, capsules are dried either in fuel kiln or electrical drier or in the sun. Soaking freshly harvested green cardamom capsules in 2% washing soda solution for 10 minutes prior to drying help retain original green colour during drying. Under flue pipe drier, it should be dried at 45°–50°C for 14–18hr, while overnight drying at 50°–60°C is required under an electric drier. The capsules are spread thinly and stirred frequently to ensure uniform drying. The dried capsules are rubbed with hands or agitated to ensure uniform drying.
Cleaning, Sorting and Grading
Dried capsules are winnowed to remove any foreign matter. Sorting and grading is done based on the size and color of the dried capsules. Graded capsules are stored in black polythene lined gunny bags to retain the green colour during storage. These bags are kept in wooden chambers and sent to market as and when required.