Cymbopogon citratus

Cultivation Details

Cymbopogon citratus is a plant of the tropics and subtropics, where it can be found at elevations up to 1,400 metre, though it grows best below 500 metres^{[1, 2]}.. It grows best in areas where annual daytime temperatures are within the range 24 - 30°c, but can tolerate 18 - 34°c^[2]. It can be killed by temperatures of 10°c or lower^[2]. It prefers a mean annual rainfall in the range 1,500 - 3,000mm, but tolerates 700 - 4,200mm^[2]. Prefers a moisture-retentive soil in full sun^[3]. Requires a well-drained soil - commercial plantations often favour sandy soils, although good growth has also been observed in Australia on a clay soil with pH 9.6 and in Sarawak on an acid peat soil[310. Prefers a pH in the range 5 - 5.8, tolerating 4.3 - 7.3^[2]. The plant tillers strongly and the number of tillers is directly correlated with the number of leaves and with oil yield. Only young, expanding leaves synthesize and accumulate essential oil^[1]. Harvesting begins when the crop is 120 - 240 days old, and the plant is subsequently harvested every 90 - 120 days^[2]. The plant has an economical life of 4 - 6 years^{[1, 2]}. The average annual foliage yield is 30 - 50 tonnes per hectare, yielding 75 - 250 kg lemongrass oil (0.25 - 0.50%)^[1]. Foliage yield of 100 tonnes per hectare has been achieved under optimum circumstances, and with efficient management and improved selections the oil yield can be increased to 0.4 - 0.6%^[1]. Harvesting the top parts gives an oil yield of 0.6%, while the lower parts yield only 0.15%^[1]. Fresh grass yields 0.2 - 0.4% oil, with an average yield of 50 - 120 kilos of oil/ha per annum. Yield of foliage is higher on fertile heavy soils, but under these conditions the oil usually has a lower citral content^[2] The plant seldom flowers^[2]. Lemongrass should be stored separately from other foods, or should be well wrapped, otherwise its strong scent will taint the other foods^[3].