Strengths

  • Will not turn into an invasive species or weed.
  • Detoxifying capacity helps clean toxic areas.
  • Drought- and frost-tolerant.
  • Requires little maintenance once established.
  • Can be introduced on farms with minimum changes to the existing farm layout.
  • Does not compete with neighbouring crops for water and nutrients.
  • Can grow in many soil types including sand, gravels and clay.
  • Can handle lengthy submergence and is suitable for the edges of dams, ponds, rivers and bridge abutments.

Limitation

  • Intolerant to shading, especially in its establishment phase; must be grown in full sun to succeed.
  • Vetiver used alone can inhibit biodiversity and native vegetation.

Vetiver grass coverage

Application: Bridges, canals, culverts and drains, drainage, embankments, floodgates, stormwater outfall

Description: Vetiver grass (Chrysopogon zizanioides) is planted as a hedgerow along the contours of sloping land to form a dense vegetative barrier that slows run-off, helps the water soak into the soil rather than washing off the slope, and provides significant soil reinforcement through its roots. With a deep and strong root system, a wide range of pH tolerance, a high tolerance to most heavy metals, an ability to remove nitrates, phosphates and farm chemicals from soil and water, vetiver grass can be an important tool to reduce erosion, improve groundwater recharge, remove pollutants from water, reduce the risk of flooding, and improve economic benefits to communities. Vetiver is native to India, is sterile, non-invasive and has to be propagated by clump subdivision. It is a low-cost, labour-intensive technology.

Contribution to climate resilience: The planting of vetiver grass reduces erosion by protecting the soil from the impact of intense rainfall, slowing down run-off, facilitating water absorption and strengthening the soil with its roots. By these means it increases the resilience of roadside slopes to extreme climatic events. Because it is planted using local labour and locally available materials, it requires less energy, is far more sustainable, and can often be applied in a quicker timeframe than traditional civil engineering works.

Supplementary sources of information:

http://www.vetiver.org

http://permaculturenews.org/2009/01/19/vetiver-grass-a-hedge-against-erosion/

http://www.vetiversystems.co.nz/

http://www.theherbcottage.com/may-2015-vetiver-grass-of-many-uses/

http://www.agrowingculture.org/2012/11/vetiver-system-a-green-investment-for-sustainable-development/

Background image credit: https://pxhere.com/en/photo/1631422

This resilience-building measure is sourced from the Water Resource Adaptation Guide (2019) published by the National Council for Sustainable Development at the Ministry of Environment in Cambodia. The full Guide is available to download at URL https://ncsd.moe.gov.kh/sites/default/files/2019-10/Water%20Resources%20Adaptation%20Guide_March%202019_En.pdf