Citronella (Cymbopogon confertiflorus), a cogon-grass look-alike which has various industrial uses because of its oil, can be grown here in our country. The oil extracted from citronella is highly valued because it is used in perfumes, mosquito repellants, soaps, spray, disinfectants, paints and polish.
In the Philippines, citronella production is still in the infant stage. There are only about 20 hectares planted to it in Leyte. Commercial production is feasible in 1,000 has in the towns of Babatngon, Biliran, Javier and Villaba also in Leyte.
The major buyers of citronella oil are the manufacturer if perfumes, laundry and toilet soaps, cigarettes and other allied items. U.S.A. is the world’s largest market of citronella oil.
Citronella oil is an indispensable ingredient in the manufacture of soap, perfumes and other industrial products. Our country is importing citronella grass in large quantities although the grass from which this oil is derived can be grown profitably under Philippine conditions. Citronella grass is found to be indigenous in the region. It is planted in backyard scale and used for bathing and other medicinal purposes only.
The recent economic crisis led to the realization that cultivating the crop locally would be more advantageous than importing the oil. The country could save a lot in foreign exchange by promoting the commercial planting of citronella grass.
Citronella Production Guide:
CROP VARIETIES
Citronella belongs to Family Graminae. It is an essential source of citronella oil and is predominantly grown in Java and Ceylon. There are two cultivated types – Mahapengeri and Lenabatu. These two types derived from wild “mana” grass. Cymbopogon coonfertiflorus (Stapf), which is the parent material of all commercially, cultivated citronella grass.
A. Varieties and Uses:
1. Lenabatu (Ceylon type) – Cymbopogon nardus (L) Rendle Adropogon nardus Ceylon de Jong narrow-leafed, hardier and long-lived. It is reported to contain only 15 – 65% of total acetyl sable expressed as geranial. Used as deodorant for mosquito repellant. Scent for soaps, sprays, disinfectants, paints and polish.
2. Mahapengari (Java type) – Cymbopogon winterianus Jowitt (Adropogon nardus Java de Jong) broad leafed, requires good soil and much care in growing and cultivating. This variety contains around 85% “total acetyl sable expressed as geranial. Used as starting materials for the preparation of industrially important perfumery compounds derived from “geranial” citronella.
CULTURE AND MANAGEMENT
1. Soil – a suitable area for citronella plantation could be a young field, virgin or regenerated (green-fertilized) soils. The grass thrives in any type of soil provided they are sufficiently fertile. However, a deep sandy soil offers the natural recondition for good quality oil. Although the growth of the plants on sand is meager and equally not large, the proportion of oil in relation to weight of leaves is more favorable.
2. Climate – a humid climate with regular rainfalls would probably offer the most favorable condition for good yield and quality of oil. It likewise guarantees longevity of plantings.
3. Elevation – grows in low and high altitude up to 2,000 ft. and more, but thrives best from 600 to 700 ft. altitude.
4. Plant Materials – Use tillers of citronella grass obtained by dividing old clumps. Each clump could yield about ten sturdy divisions.
5. Plant Materials Requirements – Place about two sturdy divisions or tillers to each hole.
6. Distance of Planting – Plant at a distance of 3 x 3 ft. But in poorer soil the interval may be less. A 2×2 interval is sufficient in the planting period intended to last for only a short time
7. Planting Time – Citronella requires fairly large amounts of moisture for proper establishment. Planting should be during the rainy season.
8. Land Preparation and Planting – If possible prepare the field thoroughly. However, under coconut areas, and in some other cases, just underbrush the area, dig hole and insert the plant materials vertically. Bury the tillers fairly deep, otherwise the clumps will easily work themselves out of the ground.
9. Cultivation and Weeding – Hill-up (loosen the soil) and weed to improve the yield and for proper maintenance of the plantation.
However, it is advisable to practice hilling-up right after every harvest to hasten the recovery and growth of the plants.
10. Fertilization – The use of chemical fertilizers increases the grass yield, however, higher yield of oil is obtained on fresh soil as compared to chemically fertilized soil. Green fertilization makes the soil loose and has a favorable influence upon the oil content of the citronella. Apply urea or 16-20-0 at 2-3 bags/ha. either basal or as side dressing.
11. Pest and Diseases – In their natural habitat these plants are not prone to pests or disease. Also this plant is largely free from pest and diseases because of aromatic smell.
HARVESTING
1. Time of Harvest – The usual practice is to harvest 9 months after planting. However, under Leyte condition, harvest eight months after planting. Three to four harvests could be done a year under favorable conditions. The rainy season harvest is usually larger than the dry season harvest.
2. Proper Time for Cutting – It is very important to choose the most appropriate time of harvesting the grass. A too short growing period decreases the productivity of the plants to such extent that a field can perish within a short time. Along growing period permits the plant to develop its full root system, which is important for longer life span. However, definite cutting period cannot always be indicated in a climate where the rainy and dry seasons are quite irregular. Proper timing for cutting is advisable in order to prevent the grass from flowering. The best time for cutting seems to be when the stem has six adult leaves with the seventh leaf in rolled up position.
3. Proper way of Cutting – Cut the leaves about 6-8 inches above ground level. Too low cutting results to the inclusion of many nearly oil-free parts of the blades which, when distilled, diminish oil yield. After the grass is cut, remove the old, dry leaves from the fresh leaves before the leaf bundles are hauled prior to processing.
4. Life Span of Citronella in the Field – Short intervals between growing periods of ratoons shorten the life span of citronella in the field. The plantation will be productive for only slightly more than two years. However, in fertile soils where greater care is taken during the growing period the plantation may last from four to five years.
Less productive fields should be discontinued because of citronella is rather a soil exhausting crop and prolonged growth of the grass in it may be detrimental to the soil, the plants, the yield and quality of oil.
5. Yield of Oil – It is difficult to express the yield of oil on a per hectare basis in definite figures because it depends on so many factors: climate, fertility of the soil, age of plantation and method of distillation.
The average yield of oil is about 0.7%. It fluctuates from 0.5% in the rainy season to 1.2% during the dry season. The estimated yield of grass range from 12 – 35 metric ton/ha. with 0.7% average yield of oil or 84 –247 kg. of oil per hectare.
References: DOST Biliran, Provincial Science and Technology Center / Citronella, assamagribusiness
For more information, please visit or call:
Bureau of Plant Industry – Crop Research Production
692 San Andres Street Malate, Manila, Philippines
Phone: (02) 8525-7313 / (02) 8525-7857
Fax: (02) 8521-7650
