Syzygium aromaticum (L.) Merrill & Perry
Family
Myrtaceae
Synonyms
Caryophyllus aromaticus L., Eugenia aromatica (L.) Baill., Eugenia caryophyllus (Sprengel) Bullock & Harrison.
Vernacular Names
Malaysia | Chengkeh, chingkeh. |
English | Clove. |
Indonesia | Cengkeh. |
Thailand |
Kanphlu. |
Philippines | Klabong pako, clavo de comer. |
Myanmar |
Lay-hnyin. |
Cambodia | Khan phluu, khlam puu. |
Laos | Do:k chan, ka:nz ph’u:. |
Vietnam | Dinh h[uw][ow]ng. |
French |
Clou de girofle. |
Geographical Distributions
Syzygium aromaticum was first cultivated on some islands of the Moluccas, where it occurs wild, as well as in New Guinea. It is found in abundance as a second-storey forest tree on the lower mountain slopes. The crop and its trade have a long and fascinating history going back to the Han Dynasty in the 3rd Century BC. The story of S. aromaticum trade and the spread of the crop are full of intrigue and brutality. Apart from pepper (Piper nigrum L.), no other crop may have played a comparable role in world history. Early in the 17th Century, when the Dutch ousted the Portuguese from the Moluccas, S. aromaticum cultivation had spread to many islands. Under Dutch rule, the crop was forcibly eradicated everywhere but concentrated on Ambon (a southern island of the group) and 3 nearby small islands. This is the wettest part of the Moluccas. From the Moluccas, S. aromaticum was taken to other parts of Asia: early in the 19th Century, the British took plants to Pinang (Malaysia), Sumatra (Indonesia), India and Sri Lanka. In the 20th Century, much material had spread throughout Indonesia. During expeditions in 1753, 1770 and 1772, the French appropriated some offsprings from trees that must have escaped the Dutch axe, and took them from the North Moluccas to Mauritius. These plants gave rise to the clove populations outside Asia, in Zanzibar, Madagascar and recently also in Bahia in Brazil.
Description
Syzygium aromaticum is a slender, evergreen tree that can grow up to 20 m tall, and appears conical when young but becoming cylindrical later. In cultivation, it is usually smaller and branched from the base. The roots form an extensive and dense mat close to the surface with some major laterals, from which occasional ‘sinker’ roots descend. The shoot growth is determinate, appears in flushes and forms a dense canopy of fine twigs.
The leaves are arranged opposite, simple and hairless. The petiole is 1-3 cm long, reddish and somewhat thickened at the base. The blade is obovate-oblong to elliptical, measuring 6-13 cm x 3-6 cm, with very acute base, acuminate at apex, coriaceous, shiny and gland-dotted.
The inflorescence is terminal, resembling a panicle, measuring about 5 cm long, with 3-20(-40) bisexual flowers and usually borne in groups of 3 cymes. The flower buds are 1-2 cm long and constitute the cloves just before opening. The sepal is tubular, with sub-cylindrical to subquadrangular tube, measuring 1-1.5 cm long, yellowish-green with a red flush and slightly protruding beyond the ovary (hypanthium). The sepal is with 4 ovate-triangular, fleshy lobes which are 2-4 mm long. The 4 petals are coherent, tinged with red, rounded, measuring 6 mm in diametre and shedding as an hemispherical calyptra as the flower opens. The stamens are numerous and measuring up to 7 mm long. The pistil is with a 2-celled ovary, with style 3-4 mm long and with 2-lobed stigma.
The fruit (called mother of cloves) is an ellipsoidal-obovoid berry, measuring 2-2.5 cm long, dark red and usually containing only one oblongoid seed 1.5 cm long..
Ecology / Cultivation
Notions about the ecological requirements of Syzygium aromaticum vary, perhaps because of an underlying dilemma: a climate with a marked dry season promotes flowering, but the tree does not cope well at all with stress. There are two ways out of this dilemma. The first is to choose a climate with a pronounced dry season (Zanzibar, East Java), but to limit stress by going for deep fertile soils, providing water and shade during the early years. The other way is to choose a wet climate with a short dry season (Madagascar, Sumatra, Pinang).; The choice is linked with the use of the product. S. aromaticum from wet areas are less suitable for making cigarettes, since the smoke becomes pungent and there is no crackling (‘kretek’) sound during smoking. In Indonesia, S. aromaticum for making ‘kretek’ cigarettes is said to require 3 months’ time in which the monthly rainfall is less than 60 mm; whereas for S. aromaticum to be used as spice, rainfall should not drop below 80 mm in any month. Annual rainfall should exceed 1500 mm; wet areas for S. aromaticum usually receive 3000-4000 mm. With mean temperatures of 21°C in July and August, Madagascar is the coolest country with S. aromaticum, reaching to the Tropic of Capricorn.; S. aromaticum is almost exclusively grown on islands, but proximity of the sea may not be as necessary as it was once thought to be, nor is the crop restricted to the lowlands. In parts of Sumatra and Java, and in the Nilgiri Hills in south India, S. aromaticum is grown successfully far from the sea and at altitudes of 600-900 m. Sheltered sites are preferred, because wind causes additional stress, and strong winds are not tolerated. Shade is necessary for young trees until they are firmly established; Growth can be sustained in poor and acid soils, but waterlogging is very harmful. Adequate depth of soil is essential and water-holding capacity should be ensured in keeping up with the severity of the dry season; if not, irrigation is needed.
Line Drawing / Photograph
References
- Plant Resources of South-East Asia No. 13: Spices.