Category: propagation

(updated September 23, 2026)

This package is a suite of generic design standards and guides for Vetiver Grass Technology, grounded in research, long-term field experience and, where applicable, current engineering practice. It exists because the global spread of VGT created a need for consistency. The standards give practitioners design and implementation guidance, help agencies, consultants and contractors prepare contract-ready documentation, and set minimum technical requirements for design, plant material, installation and quality assurance.

They are deliberately generic. VGT is a nature-based technology, and local soils, climate, hydrology, effluent characteristics and regulation all shape how it performs. Adapt them to your site, your regulatory framework and your project objectives. Do not apply them rigidly.

Every module contains a table of contents and a reference list supporting its design logic. Links point to Google Drive; internal table-of-contents links work only once the file is downloaded.

Each module carries one of three designations. GUIDE = our best estimate drawn from field practice, not yet advanced enough for a standard designation. DS = Design Standard — applications that can carry strict design parameters based on measured and demonstrated results. SPEC = contract and bidding specification, issued only for modules designated DS. A site that needs a contract specification is, by definition, a DS site.

Start here

Vetiver Hedge Mechanisms (v3.1 -new)— above ground, below ground, structural, operational and solute roles. The physical and biological basis for everything else in the package: how a hedge slows water, spreads it, builds terraces, reinforces soil and moves nutrients. Read this before choosing a module. Vetiver and Water: Hydrology, Hydraulics, and the Hidden Benefits (v1.0-new) Where Vetiver Hedge Mechanisms sets out the parts of the hedge, this one isolates the single function that underlies most of them and is the one most often misread — the management of water. It is written to be read before the application modules (A–D), because in almost every one of them the first and most important design decision is what you intend water to do. Hedge or Stand-alone (new) is a decision guide — five planting forms, when and why to use each, and the six mistakes that recur everywhere. This “quick” guide supplements the matrices below Vetiver Planting Guide (revised)— planting instructions covering nearly all applications. Plant material, root and shoot trim, crown depth, spacing, firming and gap-filling.

 

Background reading — the science behind the standards

 

Vetiver Roots: The Vetiver System Technology Hidden Half  —  Dr. Paul Truong, The Vetiver Network International, 2022, 173 pp. Paul Truong has done more than anyone to put the Vetiver System on a measured footing, and this book is where the belowground half of that work is gathered. It is not a design standard and does not tell you what to build. It tells you why the standards say what they say. It covers root growth, distribution and lifespan; root responses to flooding, drought, salinity, aluminium toxicity and heavy metals; penetration of compacted and mechanically resistant soils; interactions with soil organisms including mycorrhizal fungi; and the principles of slope stabilisation, with their limits stated. It is also extensively photographed — root excavations, roots driven through compacted dam walls, shaded against open-grown plants, root systems at depth — a visual record of the hidden half that exists nowhere else and is worth the download on its own. A concrete measure of its value rather than a compliment: reading it systematically produced version 2 of the Mechanisms standard, which withdrew an apparent root cohesion figure the manual had carried since its first revision, corrected two statements, and added five new items to its register of open questions. Very few reference works earn their keep that visibly.

 

Choosing a module

Modules are grouped in four domains — A water and hydrological protection, B slopes, earthworks and geotechnical stability, C wastewater, effluent and pollution control, D livelihoods, products and community systems. Work from the problem, not the domain:

Your problem	Start at
Canal, river or stream bank erosion	A1
Gully head-cutting and channel loss	A6
Reservoir or dam draw-down zone, fluctuating water level	A1
Farm-scale soil and water loss	A5, D3, D12
Shallow slope or embankment failure	B3 (simple slopes); B1 if the site fails the Module B screening gate
Engineered slopes (steep, difficult, high risk)	B1
Failed or reactivating slope (landslip)	B2 (shallow and inactive); B1 if active, deep-seated or large
Slopes and construction on Vertisols (black cotton soils)	B5 (small works), D12 (farm scale); B1 for public roads, dams and canal embankments
Road-drain sediment, construction runoff, post-fire slopes	B3 (Schedules E and F)
High-strength wastewater — coffee, POME, landfill leachate	C1, C5
Raw sewage	C2, C8
Polishing treated effluent to a compliance standard	C3
Urban and residential storm water management - Rain Gardens	C6
Residential plot mixed source drainage	C7
Lake, tank or reservoir pollution	A1, C10
Export floriculture efffluent	C9
Community income and adoption	D1, D2, D9, D13. D15
Soil biology, pests, nematodes, forage	D4–D8
Soil Carbon, soil health	D14, D12, D5
Planting technique	D4, D16
Nursery management	D18
Plant Quality Requirements	D17

Many sites need more than one module. Common pairings: B1 + C5 for landfills; B1 + C2 for sewage lagoons; A6 + A5 for degraded catchments; A3 + A4 for hydropower reservoirs; any C module + D1 for community-run systems.

 Data to gather before you design

 

Hydrology	Geotechnical	Effluent (C modules)	Site constraints
Rainfall intensity and seasonality; runoff patterns; water-level fluctuation (A3, A4); effluent volumes and loading rates	Slope gradient and height; soil type and shear strength; seep lines or perched water; stability history; consequence of failure (what lies on, above and below the slope)	COD and BOD; ammonia, nitrate, phosphate; pH, EC, salinity; oil and grease (POME)	Available land; access for planting and maintenance; regulatory offsets from gas lines, geomembranes and similar

 

 What VGT can and cannot do

VGT can

• Increase near-surface shear strength and reduce shallow slip risk
• Increase infiltration in the hedge zone and reduce runoff volume and velocity
• Reduce pore-water pressure in the rooted layer
• Trap sediment and build terraces
• Treat wastewater through evapo-transpiration and nutrient uptake
• Survive nearly indefinitely anaerobic conditions so long as not totally submerged and receives a transition period
• Stabilize slopes, banks, embankments and gully works
• Supply forage, mulch, improve soil structure and health, thatch and craft material, and support rural enterprise

VGT cannot

• Replace structural reinforcement where deep-seated failure is likely. .
• Treat effluent beyond the biological capacity of the system without pre-treatment
• Grow in deep shade (stops growing at 80% shade)
• Tolerate glyphosate

Common causes of failure

Across global experience, failures come from a short and repetitive list. Each module’s design envelope carries its own risk notes; these are the ones that recur everywhere.

• Glyphosate drift. It kills vetiver outright. Keep a 2 m no-spray corridor and settle this at design stage, not in year two. Decisive where VGT is proposed alongside herbicide-based conservation tillage.
• Shade. Deep shade suppresses growth severely. Note that shading an already-established hedge is more damaging than establishing under shade, so agroforestry and orchard designs must consider canopy closure years ahead.
• Abrupt transfer into saturated ground. Vetiver does grow in waterlogged anaerobic soil, but it takes roughly three weeks to build the aerenchyma that oxygenates its roots there. Dryland-raised material set straight into standing anaerobic mud is at risk through that window. Stage the transition, or use material already raised wet. This is an establishment constraint, not a species limit — and it is the likeliest origin of the belief that vetiver cannot take waterlogging.
• Incorrect spacing, density or alignment. Off-contour alignment destroys the spreading function, which is the mechanism most field results depend on.
• Poor maintenance in the first 8–12 weeks. Includes livestock access before the hedge is established, and cultivation too close to the line.
• Overloading evapotranspiration or treatment systems. Loading beyond design capacity.
• Planting on active landslide zones. . Drainage control comes first, and the slide must have been still for at least one full wet season before planting (B2).
• Ignoring hydrological pathways. Especially seep lines.
• Treating a borderline slope as simple. Apply the Module B screening gate before design. If in doubt, escalate to B1 and a geotechnical engineer

The Modules

Note: The fifth column links each module designated DS to its specification sheet — problem definition, performance objectives, design criteria, layout, materials, installation sequence, operation and maintenance, failure modes and monitoring indicators, with numeric fields left open. Guides have no specification sheet. The modules are revised from time to time. Check the dates and version number.

A — Water and hydrological protection

Code/FIle Name	Version/date	Module	What it addresses	Specs Sheet
A1 DS-WATER-MARGINS	v2 - 08/30/2026	Water margins and watercourse banks	Engineered channels · River and stream banks · Reservoir, tank and dam margins · Lake and tank water-quality protection	v1 - 08/30/26
A5 DS-ON-FARM-SWC	v1.1 - 08/22/2026	Farm Soil and Water Conservation	Conserves soil and water; increases infiltration; reduces runoff	v2 - 8/26/26
A6 DS - GULLY STABILIZATION	v2 - 09/23/2026	Gully Rehabilitation	Arrests head-cutting; stabilizes sidewalls; reduces sediment export	n/a
A9 RETOFITTING-GLOBAL	v1 - 04/09/2026	Retrofitting Watershed infrastructure on a regional basi	Retrofitting existing constructed conservation infrastructure with VGT to improve effectiveness on a regional basis.	n/a

B — Slopes, earthworks and geotechnical stability

Code	Version/date	Module	What it addresses	Specs Sheet
B1 DS- ENGINEERED SLOPES	v4 - 8/26/26	VGT for Engineered Slopes. An integrated bio-hydro-mechanical stabilization system	Steep, high or high-consequence slopes; vetiver with geofabrics and designed drainage; pore-pressure reduction. The escalation point for all B guides.	v1 - 8/26/26
B2 GUIDE- LANDSLIP REPAIR	v2 - 09/23/26	VGT for Landslip Repair	Shallow (2 m or less), inactive slips up to 500 m²; drainage first, then vetiver. Active, deep or large slides go to B1.	n/a
B3 GUIDE_SIMPLE-SLOPES	v2 - 09/23/26	VGT for Simple Slope Stabilization	Cut and fill slopes of 35° or less and 5 m or less high. Schedules for rural roads, small embankments and pond walls, building sites, spoil, sediment traps and silt fences, firebreaks and post-fire recovery." tier now sits in B1.	n/a
B4		Reserved
B5 DS- VERTISOL-ENGINEERING	v1 - 03/01/26	Civil, Hydraulic and Geotechnical Applications on Vertisols	Small earthworks and soil–concrete interfaces on cracking clays. Farm-scale companion: D12.	n/a
B6 REF_STANDARDS-BOOK -ISLAM	Ist edition 01/01/26	Standard Specificationfor Slope Stabilization Using Vetiver Grass	Book by Dr. Mohammad Shariful Islam with a focus on Bangladesh. Listed for reference; not a TVNI standard.	n/a

C — Wastewater, effluent and pollution control

Code	Version/date	Module	What it addresses	Specs Sheet
C1 GUIDE-PLANTATION-EFFLUENT	v2 - 09/21/26	Vetiver Applications for Treating Effluent from the Plantation Industry. (replaces coffee and palm oil modules)	coffee wet processing, oil palm mill effluent, and a short statement of evidence status for the other plantation crops.	n/a
C2 GUIDE-VETIVER-LATRINE	v1 - 09/09/26	Vetiver Around Pit Latrines	Pathogen and nutrient reduction has not been measured. wall stabilization, and water removal	n/a
C3 GUIDE-TERTIARY-EFFLUENT	v2 - 09/21/26	Tertiary Treatment of Residential and Institutional Wastewater	Polishing to compliance standards; removes residual solids	n/a
C4 GUIDE EFFLUENT BED	v1 - 09/21/26	Sizing and Caring for a Vetiver Effluent Bed	For the person who owns, runs or looks after a vetiver effluent bed, and the field technician who helps them. It is not written for engineers.	n/a
C5 DS- LANDFILL	v2 -09/22/26	Vetiver Grass Technology for Landfills	Leachate Phyto-Utilization, Slope and Cover Stabilization, and Seep Control	v2 -09/22/26
C6 DS- RAINGARDEN	v2 - 09/03/26	Vetiver Rain Gardens	Utilization, Slope and Cover Stabilization, and Seep Control	v1 09/03/26
C7 GUIDE- RESIDENTIAL PLOT DRAINAGE	v1 - 09/03/26	Treating mixed household drainage	Greywater, roof and yard runoff, and sewage (septic tank) leakage — on a single residential plot	n/a
C8 GUIDE-RAW-SEWAGE-DRAINS	v1 - 09/09/26	Vetiver in Open Drains Carrying Untreated Sewage	For rural and peri-urban communities where sewage runs untreated in open drains and channels, and where conventional treatment is out of reach.	n/a
C9 GUIDE- FLOWER-EFFLUENT	v2 - 09/21/26	Vetiver Grass Technology for the treatment of export floriculture effluent	This guide sets out how VGT can be applied to reduce the nitrogen, phosphorus, pesticide, suspended solids and organic load discharged by export flower farms to adjacent surface waters.	n/a
C10 GUIDE- FLOATING ISLANDS	v3 - 09/22/2026	Vetiver Floating Islands	For pond cleanup, nutrient removal, and water-quality stabilization	n/a

D — Livelihoods, products and community systems

Code	Version/date	Module	What it addresses	Specs Sheet
D1 GUIDE-HANDICRAFTS	v1 - 01/15/26	Handicrafts	Vetiver-based craft production; rural enterprise; income for women’s groups	n/a
D2 GUIDE_INTEGRATED VETIVER OIL + SLIP PRODUCTION	v2 - 09/23/26	Integrated Vetiver Oil and Slip Production	Vetiver oil plus planting material; value chains; supply reliability	n/a
D3 DS-ON-FARM-SWC	v1.1 - 8/22/26	Farm Soil and Water Conservation	Conserves soil and water; increases infiltration; reduces runoff and erosion	v2 - 8/26/26
D4 DS- MICROBIAL ROOT DIP	v3 - 7/22/26	Microbial Root Dips for Vetiver Establishment	Farm-made inoculant to improve establishment and root regeneration	n/a
D5 GUIDE_AMF	v3 - 7/22/26	Vetiver and Arbuscular Mycorrhizal Fungi — soil health, water and nutrient transfer	Shared mycorrhizal root zone between hedge and crop	n/a
D6 GUIDE_NEMATODE	v3 - 7/22/26	Nematode Suppression and Soil Biological Recovery	Vetiver as a dead-end trap for nematodes in fields and agroforestry	n/a
D7 GUIDE_STEM_BORER	v3 - 7/22/26	Dead-End Trap Plant for Cereal Stem Borers	Stem borer management in maize, sorghum and rice; hedge design; parasitoid support	n/a
D8 GUIDE-FORAGE	v2 - 7/26/26	Forage Management of Vetiver Grass	Cutting regimes for forage yield, quality and drought reserve	n/a
D9 GUIDE_KITCHEN GARDEN	v2 - 6/11/26	Kitchen Gardens - Vetiver based	With fact sheet -Swahili	n/a
D10 GUIDE_COMPARE SPECIES	v1.1 7/26/26	Chrysopogon nigritanus (African black vetiver) compared with C. zizanioides (Asian vetiver)	Species choice; D10a adds Napier (Pennisetum purpureum) as a third comparison	n/a
D11 GUIDE_VFI-FISH	v1.1 - 08/16/26	Vetiver Floating Islands and Tilapia Farming v1.1 (revised)	Combined water quality and aquaculture production	n/a
D12 DS- VERTISOL-AGRICULTURE	v2 - 8/18/26	Agriculture, Soil Health and Water Management on Vertisols	Farm-scale companion to B5	n/a
D13 GUIDE - FARM MODELS	v1 - 6/11/26	Vetiver Farm Model Package	Seven model applications with start guides, fact sheets and support files	n/a
D14 GUIDE _SOIL CARBON	v2 - 7-26-26	Vetiver and Soil Carbon	What can and cannot be claimed for soil carbon accumulation under vetiver	n/a
D15 GUIDE - VETIVER MULCH - VETICOMPOST	v1 - 8/14/26	Vetiver Mulch Versus Veticompost	keep compost for high value crops and veges. Vetiver mulch for field crops	n/a
D16 GUIDE- PLANTING	v2.1 - 8/02/26	Vetiver Planting Guide	planting instructions covering nearly all applications. Plant material, root and shoot trim, crown depth, spacing, firming and gap-filling.	n/a
D17 DS_PLANT QUALITY	v1 - 9/03/26	Plant Quality	Description, Grading and Acceptance of Vetiver Planting Materia	n/a
D18 DS_NURSERY-MANAGEMENT	v1 - 9/03/36	Nursery management	Vetiver Nursery Establishment, Management and Planting- Material Production	n/a

Keeping the package current

These standards will keep developing, because VGT is a living technology and innovation, field learning and practitioner experience remain essential to it. TVNI welcomes feedback, case studies, corrections and technical contributions. Where errors are identified, modules are revised and the package is reissued; new modules are added as they are completed. Contradicting field evidence is as welcome as corroborating evidence, and more useful.

 

 

Disclaimer. These standards are provided as guidance only. TVNI does not assume responsibility for project outcomes. The performance and results of any vetiver application depend on the decisions, designs, supervision, and workmanship of those who plan, specify, and implement the work.