1.Vetiver Grass (Vetiveria zizanioides) with 11000 pages of scientific data has got to be the most researched grass in the world. It is a native of India and is not GM (Genetically Modified)
2.The main use for vetiver in NZ is erosion control. However Vetiver does have other uses in controlling and preventing leachate polluting waterways; cleaning up septic tank drainage fields. As you may already be aware Vetiver must be planted as a hedge (5 plants to a meter...200 mm centres) Vetiver is a sterile clone, that will not seed or sucker or spread in any manner. AND because it is a clone is able to create an integrated bio-mass of roots below ground and a truly integrated hedge structure above ground. It is in essence a living dynamic retaining wall with a life span of over 200 years.(that we know of) The roots will grow to a depth of 4 to 6 meters. Vetiver will grow to a maximum height of 1.2m and a mature hedge between 600 to 900 mm in width. Vetiver will establish a hedge of some benefit in one growing season and will continue to become stronger till mature at 3 years.
3.Vetiver has fungicide and pesticide properties. Between hedges is an excellent nursery for other plant species. Vetiver cuttings make the finest organic mulch.
4.Vetiver has a huge tolerance to soil type and pH levels, from 2.5 to 11. It can grow in any soil type from sand to swamp.
5.Although a tropical C4 plant, vetiver does grow well in northern NZ's temperate climate though some what slower in comparison with the tropics. Established vetiver will withstand frost. The tops incurring some frost damage and die back but do come away again in spring. The deep root structure is not affected. Vetiver can withstand a snap frost of -15c.
6.The recommended planting season for vetiver is from September (or after frost danger) to March. (vetiver is drought tolerant,)
7.Vetiver is not harmful to stock. In some countries Vetiver is fed as the main stock diet. However young Vetiver is susceptible to stock damage so fencing off (single wire electric) is recommended until mature.
8.It is strongly recommended that your Vetiver hedge is trimmed back to 40 cm (knee height) and a liberal dressing of fertiliser is applied each spring for the first 3 growing seasons. The trimming assists the Vetiver to tiller thereby thickening the hedge. Vetiver does respond well to a nitrogen-based fertiliser. Loves blood and bone. Fertiliser is not necessary but like all plants will respond better to feeding and care. After the 3 year period trimming is optional but recommended. A Vetiver hedge can be treated like any other low hedge.