What is Vetiver?
Is vetiver the most amazing plant ever? In short, probably. Vetiver (Chrysopogon zizanioides) is a perennial clumping grass originally from India and is the worlds answer to the need for a cheap water and soil conservation solution. Each vetiver plant grows up to 150cm high and almost as wide. With its dense and very strong upright stalks vetiver comes into its own when grown as a hedge. As well as its very useful above ground attributes, vetiver has a hidden superpower. It has a three to four meter long fibrous and incredibly strong root system that grows straight down. Vetiver is the perfect plant for preventing erosion by retaining slopes, building terraces, slowing down water and building soil. It is used all over tropical and sub-tropical regions of the world for the purpose of preventing erosion. As if this wasn’t enough vetiver is also used in the treatment of waste water, as a building material and even as a perfume! Read on to find out how you can use vetiver on your homestead.
Vetiver Hedges Prevent ErosionVetiver prevents erosion when grown as a hedge on contour. The hedges are started with vetiver slips that are planted at 10cm centers. These slips are individual grass stalks with tops and roots that have usually been cut short ready for planting. This encourages strong root growth in the new slips.
Weed control is important while the hedge is getting going but once established vetiver is drought, flood and competition resistant. Each slip will eventually become a mature vetiver clump and so over time these hedges form a dense wall of vegetation that holds back water, organic matter and sediment. Hedges slowly increase in width (to about 1m depending on management) and last for generations. The only management required is to till or cut grass on the hedge edge once the desired hedge width has been achieved. On steep slopes multiple hedges may be required and growers should read one of the many engineering tech manuals such as this one from Thailand for hedge spacing in their unique application. A hot tip for getting hedges off to a great start is to lay the top prunings from the slips horizontally on the uphill side of the newly planted slips. This creates an immediate barrier and so your vetiver hedge will start conserving both water and soil from day one.
Vetiver Hedges are Self LevellingVetiver hedges should be planted on contour so that they spread water and sediment evenly along the length of the hedge, in time creating a terrace. Hedges are self leveling to a degree though and so close enough is indeed good enough when choosing your planting lines. This is something that vetiver does very well and it is because the plant is able to send out roots from higher up its stalks when buried. This means that as the low part of a hedge fills with sediment, the plant simply re-roots higher up in the soil profile until the entire hedge is level.
I had read about this attribute early on but had no idea how useful it would be until discovering that my desired hedge line at Boobook Farm was not completely level. Within two years it was! I will give a disclaimer here. Vetiver is not going to make level ground out of your rocky hillside overnight. It is good but like any natural solution it takes time and if the technology is used inappropriately then results will disappoint.
Vetiver for Waste Water Management
Vetiver has been shown to be able to absorb and tolerate extreme levels of nutrients and pollutants. This makes it very useful plant for dealing with the waste water that is a problem wherever people live in numbers. When using the plant to treat waste water it is best to create a reed bed or wetland waste water system where water is allowed to flow slowly through a thick mat of water recycling plants (in this case vetiver). I wont give further detail as there are a number of ways to set up reed beds and the topic deserves an article to itself (I will do this in time and link here when I do). I will say that in Australia it can be difficult to get approval for a reed bed waste water treatment system. That doesn’t stop you using one for your grey water though!
Use in Perfume
I’ll be honest, I know next to nothing about the use of vetiver in the perfume industry. I do know that it is the roots that are used and that there are a number of farms growing vetiver for this purpose. Surprisingly the roots also contain a chemical (maybe it is the one used in perfume) that repels termites. While that sounds great for those with termite issues, further investigation showed that this only works when the roots are crushed and so this is one superpower that a vetiver hedge does not have.
Vetiver as a BarrierWe use the plant at Boobook Farm in two ways. Firstly we have installed two hedges on contour that work to slow water and conserve soil and organic matter. The second way that we use vetiver is as a barrier. Vetiver grows so thickly that it can be planted along fence lines or around a garden and will stop other grasses from growing into the garden beds. This creates an attractive, living barrier that can be cut several times a year to provide mulch for the gardens. It is very satisfying to grow your mulch right where you need it. You can grow it around trees or banana clumps in exactly the same way.
Pests and Diseases
I have not found any. Sure invading grasses and competing weeds can be a problem with newly planted slips but after the first few months vetiver is remarkably resilient to both insects and diseases. In fact one of the only references I could find to something that was consistently considered a pest was found to be a misunderstanding. It had been reported that the vetiver stalks can be attacked by termites but further investigation revealed that this only occurs in dry stalks that are already dead. Out of all the things to worry about on the homestead having your vetiver succumb to pests is not one of them.