It is a cash crop cultivated in eastern region of Nepal. About 2500 Metric ton (MT), which is about 33.3 percent, of the world production is done in Nepal. But the production has decreased due to natural calamities and widespread occurrence of viral and fungal diseases.
It is used as a spice and ayurvedic preparations. It has a pleasant aromatic odour, so it is used for flavoring vegetables and other food preparations. It is also used to cure throat troubles, congestion of lungs, and inflammation of eyelids, digestive disorders and treatment of pulmonary tuberculosis

Climate and Soil
It grows well under the shade of forest trees, altitude ranging from 1000-2000 meters with a rainfall of 3000-3500 mm per annum.
Deep and well drained soil loamy texture best favor its production. The soil should have a pH range from 4.5 to 6.0. Land with a more moderate slope is preferred but also can be grown in undulating and steep terrains. The soil should also contain rich organic matter, nitrogen, medium phosphorus and potash.

Propagation

Propagation is done through seeds and suckers. Seedlings are obtained by propagating through seeds. Plants yield is decreased by cross-pollination. The major pollination is done by wild bees and honey bees. Planting suckers ensures the type and high productivity if they are collected from high yielding plants.

Primary Nursery and Sowing

It is sown in September-October. Seed beds are prepared in well drained soil dug to a depth of 30 cm and left for weathering. Raised beds with 15-20 cm height, 1 meter width and convenient length, preferably 6 meters, are prepared. Well decomposed cattle manure is mixed with the soil and the surface of the bed is made to a fine tilth. 80-100 gm of seeds are sown per bed in lines spaced 10 cm apart. The seeds are then covered with fine soil and mulched with paddy straw/dry grass (10-15 cm thick). Watering is to be done regularly to keep the surface of the bed moist. Germination of acid treated seeds commences after 25-30 days of sowing. The weeding is done if required. When the seedlings attain 3-4 leafs stage, they are transplanted to secondary beds.


Polythene Nurseries

The plantations of seedlings are done in polythene bags of 15*15 cm2 with perforations at the base. The bags are filled with a potting mixture of soil, sand and cow dung in the ratio of 4:1:1. These bags are kept under shade and arranged in rows of one meter width. Seedlings with 3-4 leaves are planted in the bags in April-May and watered regularly. They become ready for yielding in 10-12 months.


Secondary Nursery

The beds are prepared of size 15*100 cm2 (height by width) and well-decomposed cattle manure is mixed with the soil and an even surface is formed. Seedlings with 3-4 leaves are transplanted to the beds in May-June at spacing of 15 cm between them. The soil is kept moist by irrigation and shading. When the seedlings attain a growth of 45-60 cm in height with 2-3 tillers, they are planted in the main field during June-July of the subsequent year.


Sucker Multiplication Nursery

Sucker should be generated only in sucker multiplication nursery to ensure that viral diseases are not transmitted through the suckers produced. The site for nursery and large cardamom plantation should be at least 500 meters away either under shade of forest or under shade pandals with 50 percent shades using agro shade nets. The soil should be well decomposed with cattle manure or compost and the trenches need to be filled to the brim. Trenches of size 30*30 cm2 are prepared with an iner space of 30 cm. Then the suckers with an emerging bud are planted at 30 cm apart in the trenches. The time of plantation is May-June. After plantation, the plant base is mulched with dried forest leaves. The multiplication is rate is about 1:8 in one year. The grown up tillers are split into units of one tiller with an emerging bud and planted to main field.


Land Preparation

Before planting, the land should be cleared of all weeds, old plants. Pits of size 30*30*30 cm3 are prepared on the contour of the hill at a spacing of 1.5 x1.5 m2 after the onset of monsoon showers. The pits are left for weathering for a fortnight and then filled with topsoil mixed with cow dung or compost at the rate of 1-3 kg/pit.


Plantation

Large cardamom grows well in forest loamy soil with gentle to medium slopes. Water logged conditions are detrimental to the growth of the plants. It performs well under shade. Seedlings/suckers are planted in the middle of the pit. Seedlings/rhizomes should not be planted very deep in the pit. After planting the seedling/suckers may be staked and the base of the plant is mulched with dry leaves.


Manuring

Well decomposed cattle manure or compost and oil cakes may be applied at the rate of 2 kg per plant at least once in two years in April-May.


Weeding

Weeding should be done in three rounds for effective control of the weed growth in the initial two to three years. Weeding can either be hand weeding or sickle weeding depending upon the intensity of weed growth. From around the plant base the weeds can be pulled out by hand and the weeds in the inter space need only be slashed with a sickle. While weeding, dried shoots and other trashed materials can be used as mulch for the soil.


Irrigation

Irrigation can be done at the rate of 40-50 litres per plant at fortnightly intervals. Irrigation can be done by gravity flow, either through pipes, sprinklers or flood irrigation through open channels.


Management of viral diseases

Plants affected by the viral diseases cannot be cured but the losses can be minimized by adopting appropriate management practices.

Keep a constant vigil to detect disease affected parts.
Uproot and destroy affected plants as soon as symptoms appear. Repeat detection and uprooting at regular intervals.
Use seedlings produced in certified nurseries.
Propagation through suckers is recommended only through certified multiplication nurseries.


Harvesting

Harvesting can be done when the seeds of the topmost capsules turn brown. Bearing tillers are cut to a height of 30-45 cm and left for another 10-15 days for full maturity. The spikes are harvested using special knives. The harvested spikes are heaped and capsules are separated and dried. The cured capsules are rubbed on a wire mesh for clearing and removal of the calyx (tail). Traditionally large cardamoms are dried by direct heating which may turn capsules to a darker browner black color with a smoky smell. So improved curing techniques are available which gives better quality and appearance.


Packaging

The properly dried capsules should be allowed to cool and then packed in polythene lined jute bags. The bags may be stored on a wooden platform to avoid absorption of moisture, which may result in fungus growth damaging the stored produce.