Start a Cultivation and Processing of Lemon Grass

  

(217).Start a Cultivation and Processing of Lemon Grass

Lemon grass (Cymbopogan flexuosus, family: Poaceae) is an aromatic plant which grows in many parts of tropical and sub-tropical South East Asia and Africa. Most of the species of lemon grass are native to South Asia, South-East Asia and Australia.C. flexuosus also known as East Indian lemon grass or Malabar or Cochin grass, has its origin in Indo-Burma region and is native to India , Sri Lanka, Burma and Thailand. A related species is C. citratus called the West Indian lemon grass which has its origin in the Malaysian region. Both the species are today cultivated throughout tropical Asia.

In India, the crop is under commercial cultivation along Western Ghats (Maharashtra, Kerala), Karnataka and Tamil Nadu, UP, Assam and foothills of Arunachal Pradesh and Sikkim.

2.  Botanical Description

Lemon grass is a tall, perennial hedge throwing up dense fascicles of leaves from a short rhizome. Leaves are long, glaucous, green, linear, tapering upwards and along the margins; ligule very short; sheaths terete, those of the barren shoots widened and tightly clasping at the base, others narrow and separating. It is a short day plant and flowers profusely in South India. The inflorescence is a long spike about one meter in length. Flower panicles are 30 to over 60 cm long.

3.  Economic Importance

Lemon grass oil is distilled from leaves and flowering tops of Lemon grass. The oil has strong lemon-like odour, due to high percentage ( over 75%) of citral in the oil, which is used as a basic raw material for synthesis  of ß-ionones used for synthesis of a number of useful aromatic compounds and Vitamin - A. Lemon grass oil is thus used as a main substitute for ‘ Cod liver oil’. Citral itself is used in perfumery for various grades of soaps, detergents, cosmetics, insect repellents, room freshners, ayurvedic preparations and flavour agent for soft drinks.

4.  Market Potential & Exports

During early fifties, India produced over 1800 MT/annum of lemon grass oil and held monopoly both in production and world trade. This situation no longer exists as Guatemala, China, Mexico, Bangladesh etc. have developed its cultivation over large areas.  Currently the world production of Lemon grass oil is around 1300 MT/ annum. However, another 600 MT of a substitute oil viz., Litsea cubeba (rich in citral) is exported by China which limits the scope for any faster growth in export trade of lemon grass oil. Synthetic citral is also available which competes with this oil and natural citral in the market.  Cochin and Mumbai are the major trading centres for lemon grass oils. The essential oil of lemon grass from India is being exported to West Europe, U.S.A. and Japan.

5.  Package of Practices

5.1  Agro-climatic Requirements

The crop grows well in both tropical and subtropical climates upto an elevation of 900 m. (above MSL). However, ideal conditions for growing lemon grass are warm and humid climate with sufficient sunshine and 250-330 cm rainfall per annum, evenly distributed over most part of the year. A temperature ranging from 20-300 C and good sunshine throughout the year is conducive to high crop yield with better oil content. In the hilly areas receiving heavy rainfall, the plant grows luxuriantly and is harvested more frequently but the oil and citral content are less as compared to the plants growing in the regions of less rainfall. Lemon grass can also be grown in semi-arid regions receiving low to moderate rainfall.

 

5.2  Soils

It flourishes on a wide variety of soils ranging from loam to poor laterite, calcareous soils. However, well drained sandy-loam soils are ideally suited for better growth, yield and oil content. Soils with poor drainage and with prolonged water logging should be avoided.

5.3  Varieties

The varieties of lemon grass grown in the country include the following :

Variety	Description
Sugandhi (OD 19)	It is adapted to a wide range of soil and climatic condition. A red stemmed variety with plant height of 1 to 1.75 m and profuse tillering. The oil yield ranges from 80 to 100 kg per hectare with 85-88 per cent of total citral produced under rain-fed conditions (with life saving irrigation).
Pragati	It is a tall growing variety with dark purple leaf sheath suitable for North Indian Plains and Terai belt of subtropical and tropical climate. Average oil content is 0.63 per cent with 75-82 per cent citral.
Praman	Evolved through clonal selection and belong to species C. pendulus. It is a medium sized variety with erect leaves and profuse tillering. The oil yield is high with 82 per cent citral.
Jama Rosa	Very hardy with vigorous growth. The variety yields about 35 tonnes of herbage per ha. containing 0.4 % oil (fresh weight basis). The variety yields upto 300 kg oil in 4-5 cuts in 16-18 months growing period.
RRL 16	Average herbage yield of this variety is 15 to 20 tonnes/ hectare / annum giving 100 to 110 kg oil. The oil content varies from 0.6 to 0.8 per cent (fresh weight basis) with 80 per cent citral.
CKP 25	A hybrid between C.khasianum X C.pendulus. Gives 60 t/ha herbage in North Indian plains under irrigation. The oil contains 82.85% citral.
Other Varieties	OD-408 - is white stemmed selection from OD-19 and is an improvement in yield in terms of oil and citral content. Kaveri- needs high soil moisture to produce luxuriant growth and is evolved for river valley tracts.

Krishna, Pragati and Cauvery are improved varieties of lemon grass suitable for cultivation in Andhra Pradesh. OD-19 is an old and established variety.

5.4  Propagation

The crop is propagated through seeds raised in nurseries or rooted slips.

5.4.1  Seed Production

The crop flowers during November-December and seeds mature in next two months viz. February-March (dry season in Kerala). For collection of seeds, the plants are maintained in good health as the yield of seeds from plants subjected to regular harvest is low. On an average, a healthy plant gives about 100-200 g of seeds. At the time of seed collection, the whole inflorescence is cut and sun dried for 2-3 days. These are then threshed and seeds are again dried in the sun and the seed remain attached with fluffy mass which is removed by beating of seed bag at sowing. These dry seed lots are stored in gunny bags lined with polythene. The seeds lose their viability if stored for a period more than one year.

5.4.2  Nursery Raising

It is advantageous to raise the plantation through transplanting of seedlings whenever there is assured source of water. The transplanting of nursery raised seedlings is found to be superior to direct sowing of seeds. The seeds are sown by hand on well prepared raised beds of 1m to 1.5m width at the onset of monsoon and are covered with a thin layer of soil. Although 2.5 kg of seeds produce enough seedlings, the recommended seed rate is 4-5 kg/ha. The bed should be watered immediately after sowing and care should be taken to maintain adequate moisture in the soil. Seeds germinate in 5-6 days and the seedlings are ready for transplanting after a period of 60 days.

5.4.3  Rooted Slips

For better quality and yield of oil it is recommended to grow lemon grass by slips obtained by dividing well-grown clumps. Tops of clumps are cut off within 20-25 cm of the root. The latter is divided into slips and the lower brown sheath is removed to expose young roots.

5.5  Land Preparation

Lemon grass is a perennial crop with a duration of 4 to 5 years. For better growth and establishment, initial land preparation is important. Two to three ploughing followed by making of ridges and furrows are necessary. Application of 10 kg Phorate or 8 to 10 kg neem cake at the time of last ploughing is recommended to control soil borne pests like nematodes, etc.

5.6  Planting

Planting is done at the beginning of the rainy season. Depending on the soil fertility status and varieties, seedlings are planted at a distance of 40x40 cm., 45x35 cm., 60x40 cm. Planting on the ridges is suggested especially in high rainfall areas. In case of rooted slips one or two slips are placed into each hole, about 15 cm deep. Planting very deep should be avoided as the plants may develop root-rot during the rainy season. 

5.7  Irrigation

The improved varieties of lemon grass perform well with supplemental irrigation. Depending upon the rainfall and its distribution the field is to be irrigated at an interval of 3 days during the first month and 7 - 10 day intervals subsequently. After the establishment of plants, irrigation schedule is adjusted depending on water holding capacity of the soil and weather conditions. Four to six irrigation would be critical to sustain the crop yield during summer months..

5.8  Nutrition

5.8.1       Manure : Application of FYM @ 10 MT/ha at the time of final land preparation.

5.8.2     Fertilizer : The fertilizer requirements for the crop are best judged based on soil testing and ascertaining the soil fertility status. Keeping in view the biomass harvested from the crop, the normal recommended dose of fertilizers include N, P205 & K20 @ 150: 60: 60 kg/ha/year. Application of 30 kg nitrogen, and entire P2 O5 and K2O per ha as basal dose at the time of planting is recommended. The remaining nitrogen can be applied as top-dressing in 3 to 4 split doses during the growing season. In soils having low fertility levels, the dose of nitrogen should be increased. In zinc deficient soils (Uttar Pradesh), application of zinc sulphate @ 25 to 50 kg per ha. is recommended.

5.9  Intercultural Operations

The field is kept free of weeds for the first 3 - 4 months after plating. Similarly, weeding cum hoeing is done up to 1 month, after every harvest. Generally, 2-3 weeding are necessary during a year. In row-planted crops, intercultural operations can be done by a tractor-drawn cultivator or hand-hoe. Application of distillation waste from the crop can be applied as organic mulch @ 3 MT/ha which help in controlling weeds and retaining soil moisture. Chemical weed control through application of Diuron @ 1.5 kg a.i. /ha and Oxyfluorfen @ 0.5 kg a.i. /ha are effective for weed control.

5.10  Plant Protection Measures

Though several pests and diseases are reported, damage and crop loss is usually insignificant. Various pests and diseases and recommended control measures are given below :

a.  Insect Pests

Insects	Scientific name of insects	Nature of damage	Control
Stem Boring Caterpillar	Chilotrea sp.	It feeds on the stem. The central leaf gets dried up and ultimately the whole shoot dies, resulting in a significant reduction in the yield.	Folidol E 605.
Nematodes	Tylenchorhynchus vulgaris	The plants get infected.	Fenamiphos @11.2kg/ha.

b.  Diseases

Name of disease	Causal organism	Symptoms	Control
Red Leaf Spot	Colletotrichum graminicola	Brown spots with concentric rings in the centre appearing on the lower surface of the leaves. The spots may be formed on leaf sheaths and midrib. Later the spots merge to form bigger patches and the affected leaves dry away.	Two sprays of Bavistin 0.1% just after the appearance of the disease at an interval of 20 days . Three sprays of Dithane M-45 (0.2%) at 10-12 days interval.
Leaf Blight	Curvularia andropogonis	Minute, circular, reddish brown spots mostly on the margins and tip of the leaves which merge to form elongated reddish brown necrotic lesions resulting in premature drying of leaves. Older leaves are more susceptible to infection.	Spraying Dithane Z-78 (0.2%) or 0.3% Copper oxychloride at an interval of 15 days.
Little Leaf or Grassy Shoot	Balansia sclerotica	Stunted growth Little leaf formation in place of normal inflorescence.	Spraying Dithane Z-78 (0.3%) just before flowering stage at  10-12 days interval. Use of fresh seedlings for plantation and crop rotation.

5.11  Harvesting and Yield

Lemon grass flowers in winter season. The first harvest is generally obtained after 4 to 6 months of transplanting seedlings. Subsequent harvests are done at intervals of 60-70 days depending upon the fertility of the soil and other seasonal factors. Under normal conditions, three harvests are possible during the first year, and 3-4 in subsequent years, depending on the management practices followed. Harvesting is done with the help of sickles, the plants are cut 10 cm above ground-level and allowed to wilt in the field, before transporting to the distillation site. Depending upon soil and climatic conditions, the plantation lasts on an average, for 4 to 5 years. The yield of oil is less during the first year but it increases in the second year and reaches a maximum in the third year; after this, the yield declines. On an average, 20 to 30 tonnes of fresh herbage is harvested per hectare per annum from 3-4 cuttings. The yield in terms of oil vary from 0.5% to 0.8% depending on the variety, season/month of harvest and age of the crop, with an average oil yield of 0.65%. The yield pattern from the crop is as under :

Year	I	II	III	IV	V
Yield of herbage (MT/ha)	16	30	30	20	20
Yield of oil( kg/ha)	104	195	195	130	130

6.  Post Harvest Processing

6.1  Drying & Distillation

The grass is allowed to wilt for 24 hours before distillation as it reduces the moisture content by 30% and improves oil yield. The oil is extracted from the wilted herb by steam distillation in stainless steel unit. The factors influencing the oil production during distillation are:

1. Storage of the harvested herbage
2. Treatment (wilting and cutting into pieces) of the material and
3. The method of distillation.

The major cause of loss is due to oxidation and resinification of the essential oil. So if the material is to be stored before processing, it should be kept in a dry atmosphere with limited air circulation. The essential oils are present in the oil glands, oil sacks and glandular hairs of the plant. Therefore, before distillation, the wilted plant material is cut into small pieces to enable them to expose directly as many oil glands as is possible. Once the plant material has been reduced in size, it must be distilled immediately to avoid oil loss. The wilted leaves are steam distilled, which takes about 3 to 4 hours. Dipping the chopped lemon grass in sodium chloride solution at 1 to 2 % concentration for 24 hours before distillation is found to increase the citral content. The recovery of oil from the grass ranges from 0.5 - 0.8 per cent. The sources of distillation technology are as under :

1. Central Institute of Medicinal and Aromatic Plants, Lucknow-226015
2. Regional Research Laboratory, Jorhat-785006
3. Herbal Research and Development Institute, Centre for Aromatic Plants, Selakui, Dehradun, Uttarakhand - 248197
4. Several State Agricultural Universities

6.2  Purification of Oil

The insoluble particles present in the oil are removed by simple filtration method after mixing it with anhydrous sodium sulphate and keeping it overnight or for 4-5 hours. In case the colour of the oil changes due to rusting then it should be cleaned by steam rectification process.

6.3  Storage and Packing of Oil

The oil can be stored in glass bottles or containers made up of stainless steel or aluminium or galvanized iron, depending upon the quantity of oil to be stored. The oil should be filled up to the brim and the containers should be kept away from direct heat and sunlight and stored in cool / shaded places.

6.4  Utilization of spent material

The residue thrown out after the extraction of oil is called spent grass. Cattle relish it when it is hot or is converted into silage by adding a dilute solution of molasses. Besides being a good source of manure and mulching material, the spent grass is used as fuel for distillation after drying and also as  low cost packing material for fragile objects.

7.  Model Unit Size

Post harvest processing /distillation facility is critical for commercial cultivation of the crop since the economic product is the lemon grass oil. The minimum viable capacity of the distillation unit is 500 kg per charge (4 to 5 hours processing cycle) with which about 1000 kg (1 MT) of herbage can be distilled per day in two shifts. Assuming 300 production days, the unit can handle a production of 300 MT of herbage per annum. Assuming an average production of 25 MT herbage /ha/year, an integrated production cum processing unit with 12 to 15 ha under lemon grass cultivation and a distillation facility with a capacity of 500 kg/charge is considered economical. If the crop is to be promoted for cultivation by small farmers, availability of distillation facilities in the near proximity are to be ensured. In the present profile the following bankable models are worked out

Model I : Cultivation of Lemon Grass in one hectare and utilizing the existing distillation facilities in the proximity for custom distillation.

Model II : Integrated production cum processing facility with cultivation of lemon grass in 12 hectare and establishment of distillation unit of 500 kg per charge capacity.

The cultivation expenses for one hectare model are worked out taking into consideration the recommended package of practices and prevailing cost of various inputs and labour.     

8.  Financial aspects

8.1  Unit cost

The item wise unit cost for 1.0 ha model of lemon grass is given in Annexure I A.  The unit cost per hectare works out to Rs.41000/- spread over 1 year.  The unit cost of an integrated unit for cultivation (12 ha) and processing of lemon grass is given in Annexure I B and the same works out to Rs.785000/- spread over 1 year. The techno economic parameters are furnished in Annexures II A and II B for Model I & II respectively.

8.2  Margin money

The margin money / down payment prescribed is 5%, 10% and 15% of the total cost of development / unit cost for small, medium and other farmers respectively.  The rest of the cost of development will be provided as bank loan.  In the present model, 15% of the total cost of development i.e., Rs.6200/- has been considered as margin money for Model I. In Model II, 25% of the total cost of development i.e., Rs.196300/- has been considered as margin money.

8.3  Bank loan

Bank loan of 85-95% of the total cost of development shall be available from the financing institution.  The bank loan considered for Model I is Rs. 34800 i.e., 85% of the total cost of development.  The bank loan considered for Model II is Rs. 588700 i.e., 75% of the total cost of development.  A summary of the project cost, margin and bank loan is given below :
                                                                                (Amount Rs.)

Sl.No.	Particulars	Model I	Model II	Reference
	Model details	Lemon grass cultivation in one ha	Integrated unit with lemon grass cultivation in 12 ha and distillation unit
1	Project Cost	41000	785000	Ann. I A & I B
2	Margin	6200	196300
3	Bank Loan	34800	588700

8.4  Rate of interest

Banks are free to decide the rate of interest within the overall RBI guidelines issued from time to time.  However, the ultimate lending rate has been considered as 12% for working out the bankability of the project.

8.5  Security

Banks are guided by RBI guidelines issued from time to time in this regard.

8.6  Financial analysis

Sl. No.	Financial Indicators	Model I	Model II	Reference
i	NPV	62385	645354	Ann. III A & III B
ii	BCR	1.55 : 1	1.44 : 1
iii	IRR	> 50%	> 50%

8.7  Repayment schedule

Based on the cash flow the detailed repayment schedule has been worked out.  The repayment period works out to four years for both Model I and Model II.  The detailed repayment schedule is furnished in Annexure IV A and IV B for Model I and Model II respectively.

9.  Conclusion Cultivation of lemongrass and its processing is a technically feasible, financially viable and bankable activity in the areas identified suitable for it based on agro climatic conditions.  Lemon Grass Annexure I A Lemongrass Annexure I B Lemon Grass Annexure II A Lemongrass Annexure II B Lemon Grass Annexure III A Lemongrass Annexure III B Lemongrass Annexure IV A Lemongrass Annexure IV B