Soil erosion is one of the most taxing reasons that Earth is going through in the 21st century. The soil carried off now totals 20 billion tons a year and this loss is not only severely degrading the environment but is also eroding the economic viability of countries.
Despite all the modern tools and soil conservation methods, nothing has been quite successful. It’s surprising that ultimately, a simple aromatic grass variety came up as the ideal as well as a cheap alternative.
Vetiver proves to be one of the most important aromatic grasses when it comes to restricting soil erosion and promoting soil preservation. Vetiver (Vetiveria zizanioides) is a densely tufted, perennial clump grass with stiff-leaf bases which are strong enough to hold the soil tight.
Why is Vetiver ideal for soil preservation?
It forms dense narrow hedges and is planted along the contours of sloping land. Thus, it slows down the run-off and helps the water to soak into the soil rather than washing off the slope. The stiff rooting of the grass also blocks the passage of soil and debris which eventually dually builds up a soil terrace.
How to plant vetiver grass as a hedge?
Lay the vetiver plant material along the contour of the land and preferably set out with the aid of a simple “A” frame, with a space of 10cms between the grass slips.
As the vetiver grows quickly to the size of one meter, it should be constantly cut down to maintain the size of 150 mm.
The farmer can then place the thatch behind the newly planted slips to provide an instant filter to control run-off.
Vetiver is a continuous procedure, rather than engineered, which grows with the deposition of sediment.
For best results, it is suggested to rise from a two-meter vertical interval between hedges. However, this depends on the degree of slope and the friability of the soil.
It is because of their basal density that vetiver hedges can work as a hedge effectively in controlling soil erosion in comparison to lemongrass or any other shrubs.
Why is the vetiver aromatic plant the ideal choice?
Adaptable – Being a native of northern India and southern China, the annual rainfall it receives is more than 300mm, or 600mm where there is a six-month dry season. Even if there’s submergence, it can also survive more than a month.
Low Maintenance – Everything vetiver needs a good trim for the hedge to be in good shape. It is important to keep the grass from flowering otherwise the stem will die back, which inhibits tillering and slows the growth of the clump. Vetiver also regrows rapidly after the ire, although it is very fire-resistant when green and may be used as fire breaks.
Minimal Space Requirements – Vetiver has an upright growth habit, although hedges perform best when kept 500mm high and wide. Vetiver roots grow vertically for at least three meters not only do they bind the soil, but they do not compete with neighboring crops for water and nutrients.
Vetiver hedges have been in place for two hundred years. The grass is non-invasive, does not appear to have any significant pests or diseases, and does not harbor vermin. The denseness of the root and basal leaves also forms a barrier to the spread of invasive stoloniferous grasses such as couch and Kikuyu and can be used as a border around gardens.