MEDICINAL AND AROMATIC CROPS (2+1)

Cultivation

Soil

Vetiver can be grown on almost every kind of soil. Light soils, however, should be avoided as the roots obtained produce a very low percentage of oil. Well drained, sandy loam and red lateritic soil rich in organic matter are considered to be ideal as the roots produced in such soils are thick and contain more essential oil. It can be grown even in saline and alkaline soils, with a pH range of 8.5 to 10.0.

Climate
The crop prefers tropical and subtropical climate for its proper growth, development and essential oil yield. It grows luxuriantly in places with an annual rainfall of about 1000 to 2000 mm, the temperature ranging from 21-44° C and with a moderately humid climate. In the places which are otherwise suitable but have scanty rainfall, it can be grown as an irrigated crop.

Land Preparation
The land is ploughed to a depth of 20-25cm repeatedly and the soil is mixed with the recommended dose of manure and fertilizers and made ready for planting.

Propagation
Vetiver is propagated from seeds or slips. Seeding is found to be profuse in the crop, in areas where it occurs in the wild and regeneration takes place from self sown seeds and the rains received. In south India where the crop is cultivated on a large scale, the non seeding type is grown. This is propagated from slips obtained from the uprooted clumps of the previous crop. These clumps, when broken, give a number of slips. Slips that are separated from the clump and have 15-20 cm of the shoot portion, constitute the material for planting.

Planting
Vetiver is planted in rows 45cm apart with a plant to plant distance of 30cm. The planting is usually done during the months of June- July, at the advent of the rainy season. If irrigation facilities are available, it is better to plant during March- April. However in that case, frequent irrigation will be required. Two or three slips are planted in each hole of 5-8 cm depth and the soil is pressed around the hole. Late planted crop yields coarse roots which in turn, yield inferior quality oil. A spacing of 60 x 25 cm is also recommended to allow 60 000 plants/ha.

Manures and fertilizers
In order to obtain economic yields, the vetiver crop may be supported with 10t FYM, 25kg/ha each of N, P and K. While the entire quantity of FYM, half N and a full dose of P and K are applied at the time of planting, the remaining half of N is given after about 6 months of planting. A fertilizer dose of 60kg N, 22.5 each of P2O5 and K2O is recommended in Kerala.

Irrigation
In areas where rainfall is good and well distributed throughout the year and humidity is high, supplemental irrigation is not necessary. However, in drier areas, about 8-10 irrigations will be required in order to obtain the optimum yield.

Interculture
Once the plants have established and grown into bushes, the weed problem is not severe because of the nature of the bushes. However, in the newly established plantations, 3-4 weedings are necessary until the bushes are formed.