Vetiver 'rain garden' for flooding yards.

 The size is up to you.

The pit I dug is two wheelbarrow loads deep. 

This is the schematic plan. A hole layered with mulch with Vetiver planted on three sides to capture the water as it drains.

The Vetiver slips are planted fist length apart -- 10 cm -- and the whole project took just over an hour to complete. 

Location is all, of course. I wanted to stop run off draining into my shed.

The advantages of planting Vetiver, rather than using other drainage material for such a build are:

  • cheapness
  • ease of construction
  • flexibility re size and location.
  • can easily be altered at a later stage to suit adaptions to flow...or moved about ... or simply abandoned.
  • once consolidated, any silting from run off, can  be cleared from the pit  with a spade. If the pit was full of stones--as per normal rain  garden design -- that would be impossible to do. You would also need to truck in the stones.

The Vetiver hedge bordering the pit will hold back and slow down water flow by forcing the water underground until such stage as the subsoil is engorged with water. Vetiver will also filter and clean the water of pollutants and debris.

Vetiver will grow in water and can survive being submerged.

The same principles can be applied to using Vetiver instead of constructing  a French drain( to divert water flow) or digging a swale along a contour (in order to encourage seepage).