Citronella

Cymbopogon nardus/C. winterianus
Family : Graminae

History

Citronella plant is a perennial 1-2m tall bush with green to yellowish green leaves. The oldest known records of using citronella oil and leaves as perfumes in religious ceremonies were found in India about 2000 years before. First evidence of using citronella oil in Sri Lanka has been reported by Dr. Nicolas Grim in 17th century. By 18th Century Sri Lanka was a reputed exporter of citronella oil and the samples of Sri Lankan Citronella oil had reported to be displayed in World trade auctions in London and Lisbon. However with the entering of Indonesia and a few other countries in to market the demand for Sri Lankan citronella has been declined.

Products and Uses

The oil extracted from leaves and other aerial parts of the plant is the commercial product of importance. Citronella oil is used as a fragrant in cosmetic industry, soap and detergent manufacturing, polish, paint and in insecticide industry. It is a common mosquito repellent and also used in indigenous medicine as well as in flavoring food and alcoholic drinks in certain countries.

Major Growing Areas

Total extent of citronella is 1065ha. and cultivations have largely been confined to Hambantota and Rathnapura districts.

Varieties

Cymbopogon nadus (“Heen pangiri”) and Cymbopogon winterianus (“Maha pangiri”)) are the two important species grown in Sri Lanka.
Cymbopogon nadus (“Heen Pangiri”)

The “heen pangiri” plant has narrow, long shiny leaves. Leaf sheaths are reddish purple in colour and dried leaves curled down at the base of the bush. Plants are erect and height of the bush is about one meter. Roots penetrate into deep soil. Plant is native to Sri Lanka.

Cymbopogon winterianus (“Maha pangiri”)

Plant has wide, flat long leaves. Bush is large and grows up to 1.5-2m in height. Roots do not penetrate in to deep soil and plant depends on the surface nutrition. Oil has pleasant odor.

Soils and Climatic needs

Soil
Cymbopogon nadus can be grown in wide range of soils and even grown in sandy soils. But fertile acidic loam soils are preferable for Cymbopogon winterianus.

Climate:
Citronella groves well in tropical and sub tropical conditions from sea level up to an elevation of about 600m. A hot and humid condition with ample sun light is necessary for growing. An average rainfall of 1500 – 1800mm per annum is adequate for citronella as it bears dry and harsh conditions well.

Crop establishment

Planting material
Citronella is propagated by using suckers or rooted stem cuttings.

Field Planting: Field planting could be commenced in the months of April to August or October to January with the onset of monsoon rains. 90cm Χ 90cm and 60cm Χ 60cm is the recommended planting spacing for “Maha pangiri” and “Heen pangiri” respectively. Planting 2-3 suckers in a single planting point instead of 1 plant is a quick method of field establishment.

Crop management
Fertilizer application:
Recommended mixture – 750 kg / ha

Components of the mixture	Parts by weight	Nutrient in the mixture
Urea (46%N)	1.5	17%N
Rock phosphate ( 28 % P2O5)	1.5	11% P2O5
Muriate of potash (60% K2O)	1	14% K2O

Age of plantation	Maha Season (mixture Kg/ha.)	Yala Season (mixture Kg./Ha.)
1st Year (kg)	190	190
2nd Year (kg)	375	375

Weeding: Weeds should be kept under arrest and 2-3 times weeding per year is recommended.

Soil Conservation: If citronella is planted in steep slopes suitable soil conservation method should be practiced.

Crop Protection

No distinctive pests or diseases of economically important have been found in Sri Lanka.

Harvesting and Post Harvest practices

Harvesting
Harvesting can be commenced 6-8 months after field planting and repeated in every three months intervals. Aerial part of the plant is harvested 12-20cm above the ground level and allowed to wither in the field for 1-2 days prior to processing. Up to 20,000kg/ha of fresh leaves can be harvested and the yield may vary with the agronomic practices and the age of the plantation.
The oil yield can be 60 – 80 kg per hectare and 100kg per hectare for “Heen pangiri” and “Maha pangiri” respectively.

Processing:
Water or steam distillation is the main methods of extracting citronella oil commercially.

Standard quality specifications

Grade	Total Gereniol Content
Grade 1	60%
Grade 11	55%
Grade 111	53%

One volume of citronella oil should be soluble in 1-2 volumes of ethanol alcohol.

Medicinal and Chemical Properties
Chemical composition of citronella oil:

Chemical	“Heen pangiri”	“Maha pangiri”
Citronelal %	5%	>32%
Jeraniol %	18%	12-25%
Citronelol %	8%	11-15%
Total Jeraniol %	52-60%	85%