How to Plant and Maintain Vetiver Grass

Vetiver Grass Technology

How to Plant and Maintain Vetiver Hedgerows

Planting bare-root slips at the field site, and looking after the hedge

Vetiver Grass Planting Instructions v2.11 (download)

Vetiver grass can be planted in different configurations and on different media (soil or water). By far the most common is a narrow contour barrier that works like a porous weir: it traps soil particles and spreads rainfall runoff, some infiltrating at the barrier and the balance passing evenly to the land below.

Spacing in the row: 10–15 cm

A mature, gap-free vetiver hedgerow in a farmer’s field
Photo 1. A mature hedgerow in a farmer’s field. The hedge is solid with no gaps because slips were planted at the correct in-line spacing of 10–15 cm maximum. Slips planted farther apart form clumps that are slow to grow together, leaving gaps that defeat the purpose of the hedge. The next photos show clumps after 24 months at original spacings of 15, 30 and 60 cm: no gaps at 15 cm, gaps at the base at 30 cm, and very visible gaps at 60 cm.

An effective hedge is dense enough to redistribute concentrated runoff, spreading it along the upper side of the hedge where the sediment is deposited, then passing it slowly and evenly through the hedge to the land below. To establish a new hedge quickly and effectively, slips must be planted close together (10–15 cm). Close planting also prevents large gaps if 10% of the slips die.

Why spacing and alignment decide the water function

A finished hedge works as a porous weir: it slows runoff, ponds it briefly, spreads it along its length and lets it through slowly so it soaks into the land below. For the spreading function, continuity is close to all-or-nothing. An unbroken hedge spreads runoff evenly; a gappy one cannot, so a hedge that is 60% continuous does not give 60% of the benefit. Flow concentrates and speeds up through a gap, and the erosion usually appears on the slope below the gap rather than at the hedge itself.

Plant on the true contour. Once flow concentrates at a low point, one section of the line carries most of the water and the soaking-in benefit is lost along the rest. A deviation of more than about 2 cm per meter is expected to degrade spreading, and every furrow aligned to an off-contour hedge inherits the error.

More: Vetiver and Water · Vetiver Hedge Mechanisms

Photo 2. Gap comparison at 24 months: 15 cm and 30 cm spacing.
Photo 2. Gap comparison at 24 months: 15 cm and 30 cm spacing.
Photo 3. Gap comparison at 24 months at 15, 30 and 60 cm spacing.
Photo 3. Gap comparison at 24 months at 15, 30 and 60 cm spacing.
Photo 4. Overhead view of a 24-month hedge with spacing from left to right of 15, 30 and 60 cm.
Photo 4. Overhead view of a 24-month hedge with spacing from left to right of 15, 30 and 60 cm.
Photo 5. The planting objective at 18 months: a fully formed, gap-free hedge planted at 15 cm spacing.
Photo 5. The planting objective at 18 months: a fully formed, gap-free hedge planted at 15 cm spacing.

How to plant

Photo 6. Digging the planting furrow or holes. On arable land, plow a furrow on the contour.
Photo 6. Digging the planting furrow or holes. On arable land, plow a furrow on the contour.
Photo 7. Laying out planting material.
Photo 7. Laying out planting material.
Photo 8. Soaking slips in manure slurry before transplanting, good practice especially on poor, infertile sites.
Photo 8. Soaking slips in manure slurry before transplanting, good practice especially on poor, infertile sites.
Photo 9. Recommended spacing is 10–15 cm between plants.
Photo 9. Recommended spacing is 10–15 cm between plants.
Photo 10. Covering the transplants. Do not plant too deep; the crown should be just below the surface.
Photo 10. Covering the transplants. Do not plant too deep; the crown should be just below the surface.
Photo 11. Newly planted hedge.
Photo 11. Newly planted hedge.

Fertilizer and soil amendments

Fertilizer and manure

Vetiver establishes better if about 100 kg of farmyard manure (FYM) is applied per 100 running meters of hedgerow at planting. If FYM is not available, apply di-ammonium phosphate (DAP) at about 10 kg per 100 meters. FYM also improves moisture availability for the young plant and encourages soil microbes. Apply FYM and/or DAP liberally to nursery sites before planting material for multiplication. Slow-release NPK nuggets for containerized material optimize growth, though they are not essential. No fertilizer is needed for maintenance once hedges are established. Local conditions and doses vary.

Soil amendments

With better understanding of microbial activity in the root zone, especially that of vetiver, planting now often includes adding microbes, particularly arbuscular mycorrhiza. This has accelerated vetiver growth. See Paul Truong’s book Vetiver Root – The Vetiver System Technology Hidden Half.

Watering

Water the hedge if no rain is forecast. It settles the soil into the pore spaces and around the crown so the slip establishes faster. Keep the soil moist for at least 2–3 weeks while the slips send out new roots from the crown. If planting in the dry season, water about every 10 days until the rains begin.

Photo 12. Planted on a steep highway fill slope at 2 m vertical interval: 100% survival.
Photo 12. Planted on a steep highway fill slope at 2 m vertical interval: 100% survival.
Photo 13. A properly planted hedge: good spacing, and watered.
Photo 13. A properly planted hedge: good spacing, and watered.
Photo 14. Machine planting is useful where labor is expensive. (Australia – Truong)
Photo 14. Machine planting is useful where labor is expensive. (Australia – Truong)

Spacing between hedges

Spacing between hedges is important; planned correctly it is effective and saves cost. It depends on slope steepness. Planting hedgerows at a 2 m vertical interval (VI) normally optimizes erosion control and cost. Use the table to estimate hedge distances from slope percent.

Slope, surface run and vertical interval

Slope, Surface Run, and Vertical Interval

Slope degrees

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
Slope percent

1.7
3.5
5.3
7.0
8.8
10.5
12.3
14.0
16.0
17.6
19.4
21.3
23.1
25.0
27.0
28.7
30.6
32.5
34.4
36.4
38.4
40.4
42.5
44.5
46.6
48.8
51.0
53.2
55.4
57.7
60.1
62.5
65.0
67.5
70.0
72.7
75.4
78.1
80.1
84.0
87.0
90.0
93.0
96.6
100.0
Gradient

1 in 57.3
1 " 28.6
1 " 19.1
1 " 14.3
1 " 11.4
1 " 9.5
1 " 8.1
1 " 7.1
1 " 6.3
1 " 5.7
1 " 5.1
1 " 4.7
1 " 4.3
1 " 4.0
1 " 3.7
1 " 3.5
1 " 3.3
1 " 3.1
1 " 3.0
1 " 2.8
1 " 2.6
1 " 2.5
1 " 2.4
1 " 2.3
1 " 2.1
1 " 2.0
1 " 2.0
1 " 1.9
1 " 1.8
1 " 1.7
1 " 1.7
1 " 1.6
1 " 1.5
1 " 1.5
1 " 1.4
1 " 1.4
1 " 1.3
1 " 1.3
1 " 1.2
1 " 1.2
1 " 1.2
1 " 1.1
1 " 1.1
1 " 1.0
1 " 1.0
Surface Run (a) meters

57.3
28.7
19.1
14.3
11.5
9.6
8.2
7.2
6.4
5.8
5.2
4.8
4.5
4.1
4.0
3.6
3.4
3.2
3.1
3.0
2.8
2.7
2.6
2.5
2.4
2.3
2.2
2.1
2.1
2.0
2.0
1.9
1.8
1.8
1.7
1.7
1.7
1.6
1.6
1.6
1.5
1.5
1.5
1.4
1.4
The figures for the surface run are based on a vertical interval (VI) of 1 meter. To use this table, multiply the surface run by the VI: for example, with a VI of 2 meters on a 70 percent slope, the surface distance between vegetative barriers = 2 x 1.7 = 3.4 m
Surface run figures are based on a vertical interval of 1 meter. Multiply the surface run by the VI: for example, with a VI of 2 m on a 70% slope, the surface distance between hedges = 2 × 1.7 = 3.4 m.

Looking after the hedge

Hedgerow maintenance is important, especially in the first year, to make sure the hedge establishes properly. After that, maintenance depends on whether the aim is to keep a “pure” vetiver hedge or, more passively, to allow native plants eventually to take over.

Trimming

Trimming provides leaves for mulch to protect the young hedge in its first year, and encourages the plant to tiller and thicken. A good rule of thumb in the first year: trim when plants reach 40–50 cm, cutting back to 20 cm. Annual cutting also stops old leaves shading the center of the clump, so tillers keep regenerating from the center.

Once established, cut at least once a year but never below 30 cm. Thirty centimeters of stiff standing stem keeps the porous weir working, while the cut leaves return nutrients to the land between hedges.

Weeding and mulch

Weeding new hedgerows promotes vigor; once established, vetiver tolerates weeds between hedgerows with no ill effect. The exception is vines such as kudzu (Pueraria montana) that can grow over and smother hedges. Cutting hedges once or twice a year yields large volumes of biomass for mulching adjacent crops, which is especially valuable on steep, shallow land under tree crops or widely spaced crops such as vegetables and maize. Mulch lowers soil temperature, improves soil moisture and builds organic matter.

Termites

Termites eat dead stems (not live green ones), and their earth casts can smother and kill the whole plant. In bad cases, burning the hedge clears all dead material and removes the termites’ food source.

Gap filling

Fill gaps in the hedgerow as soon as they are seen, to keep a good, continuous hedge.

Photo 15. Trimming hedgerows provides mulch to protect the hedge in its first year and encourages tillering. (P.K. Yoon – Malaysia)
Photo 15. Trimming hedgerows provides mulch to protect the hedge in its first year and encourages tillering. (P.K. Yoon – Malaysia)
Photo 16. Gap filling within a hedgerow, done as gaps are observed. (Dale Rachmeler – Ghana)
Photo 16. Gap filling within a hedgerow, done as gaps are observed. (Dale Rachmeler – Ghana)
Photo 17. Mulching between nursery rows: successive cuttings increase mulch, reduce weeding and build soil organic matter as the mulch break
Photo 17. Mulching between nursery rows: successive cuttings increase mulch, reduce weeding and build soil organic matter as the mulch breaks down. (Graham Dabbs – Zimbabwe)

Further reading on vetiver basics

DocumentNotes
Vetiver System – Propagation & Planting (photo essay)TVNI photo essay
Vetiver Grass – The Hedge against ErosionPages 19–22
Vetiver Planting Guide – Australia
A Look See at Vetiver – MalaysiaP.K. Yoon
Techniques of Vetiver Propagation with Special Reference to Thailand
Vetiver Grass Propagation – VietnamPages 19–44
Vetiver Root – The Vetiver System Technology Hidden HalfPaul Truong’s book on vetiver roots
Document CenterOther propagation methods and more