Botanical name – Cymbopogon flexuosus
Common name – Lemon grass
It belongs to the family of Gramineae
Three types of lemon grasses viz. East Indian lemongrass. West Indian lemon grass (C.citratus), and Jammu lemon grass (C.pendulus) are in cultivation in our country as the important sources of cirtral.
C.flexuosus grown commercially in Kerala and nearby adjacent states.
The chief constituent of the oil is the citral, It is starting material for the preparation of important ionone viz., a -lonone – used in flavours, cosmetics and perfume and b -Ionone – used in the manufacture of synthetic vitamin A. Oil has bactericidal, insect repellent and medicinal uses. The spent grass is a source of good cattle feed and can be converted into good silage.
Spent grasses are also useful for the manufacture of cardboards and papers or as fuel.
Climate and Soil
The plants are hardy and grow under a variety of conditions. The most ideal conditions are a warm and humid climate with plenty of sunshine and rainfall of 250-280 cm per annum, uniformly distributed. Regarding the soil, it can be grown from poor soils, in the hill slopes. Soil pH ranging from 4.5 to 7.5 is ideal. As it has good soil binding nature, they can be grown as vegetative cover over naked eroded slopes.
The Medicinal and Aromatic Plants Research Station, Odakkali (Kerala) and CIMAP, Lucknow has developed improved strains viz., OD-19 and SD-68 respectively as a result of breeding and selection. The important features of these varieties are given below. These two improved varieties are now recommended for wide cultivation. Recently the RRL, Jammu has developed a hybrid strain CKP-25 by crossing C.khasianus and C.pendulus which is capable of yielding 50% and 140% more oil yield than RRL-16 and OD-19 respectively.
The soil should be well pulverized for forming the seedbed and it should be a raised bed one. Leaf mould and farmyard manure is also added to the soil while forming the bed. 15-20 kg of seeds are required for raising seedlings for one hectare. Seeds are sown in lines drawn at 10 cm interval in the beds and covered with cut grass materials. When the seedlings are about 2 months old or about 12 to 15 cm high, they are ready for transplanting.
The land is cleared of the underground vegetation and pits of 5 cm cube are made at a spacing of 15 x 10 cm. Splits for old clumps can also be used for propagation.
Manures and fertilizers
The Aromatic Plants Research Station Odakkali (Kerala) recommends 100 kg of N/ha. Under North East conditions, application of 60kg of N, 50 kg P and 35 kg K is recommended per hectare. In North India, Jammu lemon grass (C.pendulus) is cultivated under irrigated condition as a source of citral. The cultural practices are almost similar to East India lemon grass. It is propagated exclusively by slips, which are planted on flat beds. A spacing of 50 x 50cm is adopted. A dose of 260 kg N, 80 kg P2O5 and 120 kg K2O per hectare is recommended in 3-4 split doses. The crop responds to irrigation especially during hot summer months.
Lemon grass comes to harvest 90 days after planting and subsequently it is harvested at 50-55 days interval. The grass is cut 10 cm above the ground level and 5-6 cuttings can be taken in a year subject to the climatic conditions. Depending upon the soil and climatic condition, the crop can be retained in the field for 5 to 6 years. Depending upon the planting period, one or two cuttings are taken in the first year and from second year onwards, 3-4 cuttings are available. Harvesting consists of fresh leaves and also the dry or semi-dried leaves at intervals of 60 days. The crop should not be allowed to flower profusely as it reduces the overall yield.