Cul t i vat i onof Pat choul i
Patchouli Area Under Cultivation It is cultivated in Bangalore and coastal areas of South India, Bengal and Assam.
Botanical Name : Pogostemon patchouli Family : Lamiaceae Plant Discription : It is a branched,erect or ascending pubscent herb or undershrub with quadrangular stem about 1 to 1.2 m tall.The leaves are simple,ovate to oblong ovate, pale to purplish green in colour. It does not flower under cultivation.
Centre of Origin : Phillipines Pollination System : Self pollinated Chromosome No. : 2n=32
Patchouli Diseases Leaf Blight (Cercospora sp) Mostly when the plants are almost one year old brown spots are formed near the margin or at the apical region, which enlarge irregularly, coalesce, cover the entire lamina and create drying. It is, however, not of common occurrence and less serious as compared to root-knot. Control : The disease can be controlled with two sprays of Dithane Z-78 0.5%, at one-month interval. This, however, depends upon the severity of the disease.
Patchouli Harvesting The first harvest of the crop is taken about 5 months after transplanting. The stage at which crop has to be harvested is very important for good yield and better quality of oil. It has to be harvested when the foliage becomes pale green to light brownish and when the stand emits characteristic patchouli odour, which could be easily smelt by a passer-by, especially in the morning hours. Subsequent harvest can be taken after every 3-4 months depending upon the local conditions and management practices. The crop can be maintained for about 3 years. The first 2 or 3 harvests of newly planted plantation give good yield and high quality oil. Harvesting is done with the help of small sharp shear or secateur. Usually the length of the harvested portion ranges from 40-60 cm. It is necessary to leave 4-6 juvenile sprouting buds at the basal region for fast regeneration, while harvesting. The crop should not be harvested prematurely as it gives less yield and oil of inferior quality.
Yield : The oil is found mainly in the leaf and small quantity is present in the ender parts of the stem. The yield of fresh leaves/ha/year from three harvests is about 8,000kg which on shade drying reduces to 1600kg and on distillation yields about 40kg of oil. The yield of oil varies from 2.5 to 3.5% on shade dry basis of the leaves and an average yield of 2.5% may be considered satisfactory in commercial distillations.
Uses : The oil of patchouli is used so extensively it is very difficult to specify its field of application. It blends well with sandalwood, germanium, vetiver, ionones, cedar wood derivatives, clove oil, lavender, bergamot and many others. The oil is almost a perfume by itself. It is widely used in soap, cosmetic, tobacco and incense. The oil gives one of the finest attars when blended with sandalwood oil. The oil possesses antibacterial activity and it is used as an ingredient in insect repellant preparations. The leaves and tops are added in bath for their anti-rheumatic action. It is also used as a masking agent for alcoholic breath. Tenacity of odour is one of the virtues of patchouli oil and is one of the reasons for its versatility.
Patchouli Manuring & Fertilization Patchouli requires rich soil in order to obtain proper yield and better quality of oil. Normally, a basal dose of 25 kg N, 50 kg P2O5 and 50 kg K2O per hectare is given in the form of Urea, Superphosphate and Muriate of potash. After about two months, 25 kg N as urea is applied. Likewise, for each harvest 50 kg N is applied in two split doses, the first dose just after the harvest and the other about two months later. In total, 150 kg N per hectare per year is applied to the crop.
Patchouli Irrigation For getting good yield of the crop, the area should receive good and evenly distributed rainfall, because it does not do well under rainfed conditions. Immediately after transplanting the field must be irrigated every day for the first 3 to 4 days and subsequently on alternate days for 10 to 15 days. After three weeks irrigation once or twice a week depending on the type of soil and climate is considered sufficient. The crop is highly susceptible to water logging.
Patchouli Intercultural Operations The field should be kept weed-free during the first 2 to 3 months of crop growth either by hoeing 2 to 3 times or by hand weeding. Weeding is also necessary after about a month of each of the foliage harvests.
Patchouli Pests Root-knot Nematode (Meloidogyne Incognita) The nematode is an obligate parasite which enters into the root by thrust with the mouth spear, usually in the region of cell elongation or at the base of lateral roots. They reach cortex, multiply and cause galling which is commonly called as root-knot. The diameter of the knots varies from 0.2 cm to 5.0 cm. Heavily infected plants show stunting of top growth and wilting. Initially it will be difficult to differentiate between the infested and healthy plants. Typical symptoms of an infested plant become apparent only after 8 months. In case of severe attack the crop dwindles and the whole stand may perish during the next 2 or 3 months. The plot should be treated with a proper nematicide. Furadan @ 20 kg / ha (3% a.i.) or Dasanit 150 kg /ha (5% a.i.) are found to be very effective. First dose of the nematicide should be given as a preplanting treatment and the second dose can be given one year after transplanting as pocket application to the plants. In order to get a good crop of patchouli in nematode-infested soil, it is desirable to take a crop of citronella or other nematode-resistant crop for next few years before planting patchouli. Nursery should be raised from healthy mother stock under nematode-free conditions. Application of farmyard manure should be avoided
Patchouli Post Harvest Technology Drying The harvested material is spread out under shade in thin layers and is turned periodically to ensure proper drying. For higher recovery and good quality of oil, moisture content of herbage should be between 2.5 and 8.3%. Drying normally requires 3-6 days. It, however, depends much on available sunshine and atmospheric humidity. Properly dried leaves develop characteristic patchouli aroma, which is less noticeable in fresh leaves.
Distillation Shade-dried leaves of patchouli are subjected to steam distillation for obtaining the oil of patchouli. The dried herb could be immediately distilled or could be stored for sometime according to convenience. Proper dried leaves produce good oil yield and better quality of oil. The distillation equipment needed for distilling the oil consists of boiler, distillation still, condenser and receiver. The distillation still is generally made up of mild steel. It has a perforated metal sheet at the bottom to support the herb, which is loaded into the still for distillation. Loading and unloading can be mechanised with the help of an over-head chain-pulley block. The lid of the still can be swung aside during loading and unloading. It is important that the herb should be evenly packed inside the still as otherwise steam channels may form during the distillation resulting in poor yield. The condenser, which cools the hot vapours, received form the still consists of many tubes made up of copper or stainless steel and mounted inside a jacket. The condenser is provided with inlet and outlet for the circulation of cooling water. The hot vapours consisting of steam and essential oil vapours are cooled in the condenser tubes and the condensate then flows out into the receiver. The oil being lighter than water and insoluble floats on the receiver and only the water gets drained out. The oil can be drawn off separately at the end of the distillation. The receiver id fabricated out of stainless steel and consists preferably of two compartments, so that the oil escaping from the first compartment can be retained in the adjoining compartment, which of course rarely happens. The process of distillation consists of loading the dried leaves into the still, closing the lid securely, letting in steam (generated in a boiler) from the bottom of the still, condensing the vapours I the condensor and collecting the oil in the receiver. It has been noted that interchange of high and low pressures, i.e., 1.4 to 3.5 kg/sq. cm produces better yield as more cell walls rupture in this process. The duration of the distillation varies from 6-8 hours. Prolonged distillation gives higher yield and better quality of oil. But if it is distilled for to long, the oil will have disagreeable odour. Patchouli resinoid is also prepared occasionally by extracting the have with volatile solvents such as benzene. Such extraction gives 4.5 to 5.8% of resinoid, which contains 70-80% of alcohol-soluble absolute.
Patchouli Planting Land Preparation The main field for transplanting is thoroughly disced and tilled. Suitable nematicide, viz., Furadan @20 kg/ha.(active ingredient 30%) or Dasanit @ 150 kg/ha (active ingredient 5%) is broadcast and mixed well into the soil a few days before transplanting. The plot is then laid out in ridges and furrows. The ridge should be 20-25 cm high and 18-22 cm broad with 60 cm row to row distance. The beds should be irrigated a day before the transplantation.
Shading Patchouli is a shade loving plant. It is felt that patchouli could be tried under coconut in India. It could also be taken up with some suitable crops that provide adequate shade. Gliricidia or Erythrina could be planted well in advance at 5 X 5 m spacing in patchouli field in order to provide the necessary shade.
Method of Planting Rooted cuttings are transplanted generally in the evening in the main field. The planting is done at 60 x 60 cm apart. Normally 28,000 cuttings will be required per hectare. Irrigate the field immediately after transplantation. Planting of 15-20 cm long unrooted cuttings is also practiced in some areas. These cuttings are planted at the rate of 2 to 3 cuttings per hill. During early stages shade and sufficient moisture are most important requirements. Shade can be removed after the plants establish well.
Patchouli Propagation Raising Seedlings in Nursery Patchouli is propagated vegetatively. Since the crop is highly susceptible to nematode attack, it is advisable to adopt phytosanitary measures from nursery stage itself. Seed pans or polythene bags are filled with well-heated sand, which can be made by passing steam through it for about one hour. If this is not practicable for a grower, the sand should be treated with suitable nematicide like Furadan @ 20 kg/ha (active ingredient 3%). Dasanit @150 kg/ha (active ingredient 5%) is also very effective.
Nursery that has to be under shade could be raised at any time during the year. Cuttings are prepared preferably in the morning or in the evening to minimise desiccation. Cuttings are taken from healthy stock and as far as possible from the apical region. Cuttings from fairly developed branches, 4-5 nodes in length and with a crown of 2-3 leaves, are ideal for planting in nursery. The basal end of the cutting should be neatly cut in oblique form just about 1 cm below the node. Application of a commercial hormone like Seradix B-2 to the basal end of the cutting encourages early rooting. The cuttings should then be planted in seed pans, nursery beds or in polythene bags with the help of a suitable dibbler at a spacing of about 5 cm. Aeration, partial shade and regular watering are essential for early rooting. The cuttings take about 30-35 days for rooting in nursery.
Patchouli Soil & Climate Soil Patchouli is a hardy plant and adapts itself to a wide range of soil conditions. However, it flourishes best in loose deep loamy soils, rich in humus and nutrients, with a loose friable texture and without impervious layer at the bottom. The pH of the soil from 5.5 to 6.2 is considered to be ideal. The plant flourishes in low altitudes and foothills over slightly moist, well-drained soils in tropical and subtropical conditions. It is also observes that the richest soil produces the best leaf material which gives better yield and better quality oil.
Climate Patchouli grows successfully upto an altitude of 800-1000m above the sea level. It prefers a warm and humid climate. The crop can be grown successfully on a fairly heavy and evenly distributed rainfall ranging from 1500-3000mm per annum. It is also observed that the moderate temperature of 22-28째C and an average humidity of 75% have been found to be ideal for its growth.
Patchouli Varieties Johore : This variety yields the best quality oil in terms of chemical composition and odour value.
Java : Java strain recorded the highest herbage yield but inferior quality oil.
Singapore : This strain has higher oil content and was thus superior to 'Java' in oil yield.