Cardamom

Description

Cardamom, Elletaria cardamomum, is an herbaceous perennial in the family Zingiberaceae grown for its fruits which are used as a spice. Cardamom is a clumping plant with between 10 and 20 leafy shoots arising from the rhizome. The shoots are actually pseudostems composed of overlapping leaf sheaths. There are several additional flowering shoots. The leaves are lanceolate and dark green in color. The plant produces flowers on a long drooping pannicle and a capsule-like fruit which is triangular in cross section and initially pale green or yellow in color but dries to brown. The fruit contains 15–20 small aromatic seeds. Cardamom can reach a height of 5 m (16.4 ft) and has an economic lifespan of 10-15 years. Cardamom may also be referred to as green cardamom, black cardamom, brown cardamom, red cardamom or white cardamom and originates from southern India and Sri Lanka.


Uses

The cardamom fruit or seeds are used dried as a culinary spice. The seeds are used whole or ground. Cardamom may also be used as a flavoring in drinks, baked goods and confection.


Propagation


Basic requirements
Cardamom originates from mountainous forests and can be grown in a variety of soils ranging from forest loam to quartz gravels. It can be grown in the home garden in areas with tropical climates and elsewhere can be grown as a container plant and moved indoors when the temperature drops in the Fall. The optimum annual mean temperature for the growth of the plant is 22°C (71.6°F) and the plant will not grow below 17°C (62.6°F). As a consequence of their forest origins, cardamom plants thrive in shaded areas with indirect sunlight.

Propagation
Cardamom seeds can be collected from the mature capsules (pods) by gently pressing the capsules until they pop open. The seeds should be left to dry for a couple of days before planting in a container or outdoors in a prepared bed. For large scale production, they are commonly sown in nursery beds and transplanted to the field when they are 1–2 years old. Propagation from rhizomes is achieved by dividing the rhizome of plants that have at least three shoots. Plants are usually spaced 1.5–3 m (5–10 ft) apart allowing a further 1.5–3 m (5–10 ft) between rows.


References

Anandaraj, M. & Sudharsham, M. R. (2010). Cardomom, ginger and turmeric. In Verheye, W. H. (ed) Soils, Plant Growth and Crop Production. Eolss Publishers Company Limited. Chapter available at: http://www.eolss.net/Sample-Chapters/.... [Accessed 10 November 14] Free to access

Spices Board India. (2009). Cultivation Practices for Cardamom. Ministry of Commerce and Industry, Government of India. Available at: http://www.indianspices.com/pdf/Book_.... [Accessed 10 November 14]. Free to access


Common Pests and Diseases

Damping-off (Rhizome rot)
Pythium vexans
Rhizoctonia solani

Symptoms
Pale leaves and yellowing of plant; collapse of seedlings in nursery; more mature plants may exhibit a discoloration and decay of the rhizome; decay causes death of plants
Cause
Fungi
Comments
Fungus can survive in soil for long periods of time
Management
Soil drenches with appropriate fungicides may be used to treat the disease prior to planting nurseries; all infected clumps, including rhizomes must be removed and destroyed; plant cadomom in well-draining soils

Cardamom thrips
Sciothrips cardamomi

Symptoms
Silvery sheen or discoloration on young leaf sheaths and unopened flower bracts; damaged areas developing white, yellow and brown blotches and/or streaks
Cause
Insect
Comments
Damaged caused by feeding adults and nymphs; cardamom thrips found in Hawaii and India
Management
Regulate shade in plantation; applications of appropriate insecticide may be required

Nematodes
Meloidogyne spp.

Symptoms
Stunted, yellowing plants; galls on roots which can be up to 3.3 cm (1 in) in diameter but are usually smaller; reduction in plant vigor; yellowing plants which wilt in hot weather
Cause
Nematodes
Comments
Galls can appear as quickly as a month prior to planting; nematodes prefer sandy soils and damage in areas of field or garden with this type of soil is most likely
Management
Check roots of plants mid-season or sooner if symptoms indicate nematodes; solarizing soil can reduce nematode populations in the soil and levels of inoculum of many other pathogens

Azhukal (Capsule rot)
Phytophthora spp.

Symptoms
Water-soaked lesions on rachis; plant dries up beyond point of infection; rotting capsules with a foul odor which fall from plant; water-soaked spots on leaves which enlarge and coalesce
Cause
Oomycete
Comments
Disease emergence favored by wet, poorly-draining soils; fungus persists in the soil and becomes active during the monsoon season
Management
Plants must be protected during pre-monsoon period by removing all crop debris including diseased plants and burning; try to reduce the amount of shade on the plantation and promote good drainage

Katte disease (Mosaic)
Cardamom mosaic virus (CdMV)

Symptoms
Thin chlorotic flecks on youngest leaves of stem which develop into pale green stripes running from midrib to leaf margin parallel to veins; all leaves emerging subsequently have stripes; symptoms then spread to all tillers
Cause
Virus
Comments
Transmitted by banana aphids
Management
Check planatation for symptoms of disease at least twice each year; remove and destroy affected plants; replant with healthy material; avoid planting close to diseased gardens; do not use volunteer or tillers from infected plants as planting material