Slope Stabilization With Vetiver Grass
~ Design & Implementation ~
Contour Vetiver Grass Planting + Natural Stone Pathway
Location: Thousand Oaks, CA
Land & Climate Characteristics: South facing slope between 55-65% grade, composed of loose fill material from when the subdivision was built. Soil was chalky and very fragile, had almost no organic mater and was very hydrophobic (i.e. high run-off and erosion potential).
Client Vision And Goals: The client needed the eroding slope behind her suburban home stabilized to prevent any damage to the deck and house foundation. Safe and aesthetically pleasing access was also desired down to a lower gate that led out into the adjacent nature preserve.
Design Elements
- Access
- Installation of natural stone pathway built with “gravity glue” and anchored by vetiver grass to allow for safe access down the steep slope to the lower gate.
- Living Systems
- Vetiver grass planted in contour strips and around stone pathway edges to create living retaining walls that get stronger with time. Slope was effectively stabilized and erosion processes halted by the end of the first summer after planting (~ 4 months). Grass grew to over 6′ tall by the end of the summer, at which point it was cut and added as soil-building mulch to the hillside.
BEFORE installation of rock pathways and vetiver. 
DURING: Installing the natural stone pathway. 
After stone pathway and vetiver grass installed. 
Natural stone pathways on steep slope anchored by vetiver grass and gravity glue. 
Natural stone pathway on steep slope anchored by vetiver grass and gravity glue. 
Top of stone pathway looking downslope. 
4 weeks of growth on new vetiver slips. Slope covered in vetiver grass contour rows. 
Vetiver grass ready for its second cut at 15 months – over 6′ tall. 
Natural stone pathway held together with gravity glue and vetiver grass. 
Vetiver grass after its first cut. 
Vetiver grass is a living retaining wall, capable of anchoring large stones in place with its stiff stems. 
Mature vetiver grass grown in around rock pathway. 
Vetiver grass grows thick and tall but won’t spread or invade – it stays where you put it!