Skip to main content
Home

Main Menu

  • About
  • Contests
    • Changing Unsustainable Trade
    • Water Pollution and Behavior Change
    • Climate Change Needs Behavior Change
    • Farming for Biodiversity
    • Reducing Our Risk
    • Adapting to a Changing Environment
    • Turning the Tide for Coastal Fisheries
  • Solutions
  • Impact
    • Growing indigenous seeds with pride
    • Honey shows the way in Ethiopia
    • Revitalizing oceans and communities
    • Solar Sister Entrepreneurs
  • Log in
  • English
  • Chinese, Simplified
  • Français
  • Español
  • Indonesian
  • Portuguese, Brazil
Farming for Biodiversity

Rainforest Alliance

Colombo, Sri Lanka
Close

An Overview Of Our Solution

Encroachment on forests for agricultural production is a major driver of deforestation. Tea farmers in Sri Lanka are vulnerable to the effects of climate change and struggle to manage noxious weeds. The Rainforest Alliance, in collaboration with tea experts in India and Sri Lanka, developed and have provided training to 23,000 tea farmers on an herbicide-free weed management system. Under this system, farmers allow beneficial weeds to grow, thereby replenishing nutrients in the soil, while noxious weeds are manually uprooted and composted into fertilizer. The result: healthier soil, increased biodiversity, and cleaner streams and rivers. This system helps farms build resilience to weather events including drought, helps reduce soil erosion, and helps increase farm yields, reducing the pressure on farmers to cut down forests to expand their production.
Who is this solution impacting?
Community Type
Rural
Rural
Additional Information
  • Population Impacted:
  • Continent: Asia
General Information

Organization type

Nirlaba
Ecosystem (select all that apply)
Deserts
Deserts

Population impacted

Approximately 23,000 farmers trained & families
Challenge

Size of agricultural area

To date, training on this system has been provided to smallholder farmers who produce tea in a total of approximately 7,000 hectares

Production quantity

10,000 MT (made) tea

People employed

Tea farmers can choose to implement this herbicide-free management system. This system does not directly employ people.
Solution

Describe your solution

This herbicide-free integrated weed management solution was originally developed by a tea expert working with the Rainforest Alliance in India and helps address the challenges described above. In Sri Lanka, Rainforest Alliance, in collaboration with botanist Mahendra Peiris, manager of the Rainforest Alliance Certified Hapugastenne Tea Estate, have further developed, tested and rolled-out this solution to tea farmers. This system differentiates between noxious weed species that grow aggressively and negatively affect tea bushes and “soft” beneficial weed species which can co-exist with tea. It also allows beneficial weeds to grow, serving as a cover crop, keeping soil moisture, reducing soil erosion and, when growing densely enough, prevent noxious weeds from developing. The Rainforest Alliance engaged the Tea Small Holdings Development Authority (TSHDA), and through its train-the-trainer approach, trained TSHDA extension staff who in turn have provided training to smallholders in regions across Sri Lanka.
Implementation

Describe your implementation

Under this system, farmers selectively uproot noxious weeds manually and those can be composted for use as natural fertilizer. They keep beneficial weeds at a low height, instead of uprooting or scraping, keeping their root systems alive which helps prevent erosion and maintain soil moisture. The weed cuttings are left in the field as mulch, which help provide nutrients to the tea bushes. Weeding is timed carefully: noxious weeds are uprooted before flowering and seeding to prevent proliferation while the soft weeds are allowed to flower. Mahendra Peiris conducted a field trial on 1.5 hectares of the Rainforest Alliance Certified Hapugastenne Tea Estate in Sri Lanka, comparing this integrated weed management system with the herbicide-based management system used in the estate. The results of the 3-year long trial and related studies have been published in scientific journals. To promote the adoption of this solution, the Rainforest Alliance developed a training module on the system for its Sustainable Farming Training Platform and incorporated it to the training program for tea estates and smallholders. Between 2015 and 2016, about 23,000 smallholders were trained on the method. The field trial site is used as a demonstration and training venue which receives several groups of smallholder farmers on a regular basis. When farmers see the system applied on a large scale, they become convinced of its merits. Key success factors for the high adoption rate among smallholders include its very low cost, yield improvements, and the medicinal or nutritional characteristics that some of the soft weeds provide. For most companies, adopting this herbicide-free method would mean a radical paradigm shift, representing an obstacle to its adoption at the estate-level. However, the Rainforest Alliance can help in every step of the transition to more sustainable practices and some companies have already decided to start trials using this system in their estates.

External connections

International agencies and corporate partners provided grant funding for the Rainforest Alliance to train and implement this system with tea farmers. In Sri Lanka, the Hapugastenne Tea Estate has been a key partner hosting the field trial which has served as a demonstration and training site on the herbicide-free weed management system. The Tea Small Holdings Development Authority (TSHDA) played a key role in the adoption of this solution by providing training to smallholders in regions across Sri Lanka. The Alliance for Sustainable Landscapes Management (ASLM), Rainforest Alliance’s implementing partner in Sri Lanka, has helped build awareness about the benefits of this system with policy makers and tea sector organizations. Other stakeholders collaborating with the Rainforest Alliance include trainers and technical consultants in different countries in Asia, farmer associations, as well as some company and estate managers in Sri Lanka and elsewhere who are looking to transition to sustainable farming practices.
Results

What is the environmental or ecological challenge you are targeting with your solution?

Tea farmers in Sri Lanka are vulnerable to the effects of climate change and face extreme weather events ranging from floods to severe droughts. Additionally, farmers in both large estates and small farms struggle to manage the effects of noxious weeds. Weed management on the estates currently relies on the use of chemical herbicides, which pose ecological risks to soil health, water quality and biodiversity both at the farm-level as well as nearby ecosystems. Smallholder farmers often use methods, like soil scraping, that leave the soil in or adjacent to the tea field vulnerable to erosion. Resulting landslides put lives at risk and lead to siltation of water bodies. Some estates have introduced exotic plant species to help control erosion, however these may become invasive species. The challenge is to increase resilience to climate change and reduce the use of detrimental weed management practices, while providing a sustainable and cost-effective alternative.

Describe the context in which you are operating

Tea production in Sri Lanka represents an important land use as well as major economic activity. It is produced both in large plantations that employ a total of over 200,000 workers, as well as by nearly 400,000 smallholders, for whom it often provides an important source of income. In both production systems, inappropriate cultivation practices can lead to land degradation and depletion of natural resources on or next to tea production areas. Numerous tea estates rely on chemical herbicides to manage weeds. However, due to repeated herbicide applications, many of the noxious weeds (those detrimental to tea bushes) have developed resistance to herbicides, while most beneficial weeds are killed. This results in more herbicide applications, a “herbicide trap”. Additionally, the effects of climate change and the growing global demand for tea, are intensifying the pressure on land use for cultivation.

How did you impact natural resource use and greenhouse gas emissions?

Encroachment on forests for agricultural production is a major driver of deforestation and Sri Lanka’s forest cover has already been reduced to 28%. This system helps increase farms yields and avoid the need to clear forest lands. It also helps arrest or even reverse land degradation, while providing economic benefits for farmers. By avoiding herbicides, a wider array of plant species (i.e. beneficial types of weeds) are allowed to co-exist with tea bushes, attracting a greater number of insects and larger animals that live or feed on those plants. It also allows soil organisms, which play a key role in maintaining soil health, to thrive aiding with the long-term fertility of the land. This system thus helps increase biodiversity in tea farms compared to counterparts that rely on herbicide-based weed management. Additionally, farmer groups that have started testing and studying the system, are finding that biomass production is higher under this system than under soil scraping methods.

Language(s)

Sinhalese, Tamil & English

Social/Community

Rainforest Alliance training on this herbicide-free weed management system builds the capacity of both women and men farmers to implement sustainable practices. This system and its positive results, are helping build awareness and interest in farmers and their communities to conserve biodiversity in their farms and beyond.

Water

Chemical pollutants from herbicides can leach into groundwater or be carried in runoff into nearby waterways. Rainforest Allliance trained farmers to implement this herbicide-free system in their farms near the Kelani River, which provides 80% of the water for downstream residents in Colombo, Sri Lanka’s largest city. At the same time, the ground cover that results from this system helps reduce erosion and runoff, which also affect the health of rivers and water quality.

Food Security/Nutrition

Methods of blanket weed control (by either herbicides or soil scraping), remove both beneficial and noxious weeds. On the other hand, this system only removes noxious weeds while allowing plants with nutritional or medicinal value to grow. Some of these edible greens are part of traditional diets and farmers incorporate them in their meals. Other types are used for animal feed.

Economic/Sustainable Development

This system helps reduce costs as it requires little to no inputs (i.e. no purchases of sprayers or herbicides). Additionally, this system helps increase yields (more product for farmers to sell/use). Increasing yields in farms is critical for sustainable development as it reduces the need to cut down patches of forest to increase production.

Climate

This system increases the resilience of tea farms in the face of weather variations ranging from storms to drought. The field study at Hapugastenne estate showed that under drought conditions the plot under this system sustains production of the tea bushes for a longer period than in the weed-free control, as the soft weed cover helps hold water/ soil moisture. This results in reduced water stress for the tea bushes. During storms, it holds the soil in place reducing erosion.

Sustainability

The initial investment to develop the demonstration plot and provide training depended on external funding. Training on this topic is now integrated in Rainforest Alliance’s standard training program for smallholders in Sri Lanka. Additionally, under its train-the-trainer approach, the Rainforest Alliance also provided training to extension trainers at the Tea Small Holdings Development Authority, which in turn trains smallholder farmers in other areas in the country. Funding through grants helps the Rainforest Alliance provide training to farmers in other regions both in Sri Lanka and in other countries. For implementation, this solution only requires labor— no upfront investment in sprayers nor regular expenses on herbicides.

Return on investment

At the estate level, the field trial required a substantial investment in labor in the first year, since manual weeding required more workers. However, by year two, costs of weeding dropped by 50% as less workers could eradicate the noxious weeds completely; by then the soft weeds were flourishing. By year three, the estate crop yield had increased 20%, and overall costs had dropped as there was no longer an expense on herbicides. At the smallholder level, particularly when only family labor is used, the out-of-pocket cost to implement the system is nearly zero. Many smallholder farmers are also reporting increases in yield. Higher yields may be the result of the nutrients that the decaying weed biomass provides for the tea bushes.

Entrant Banner Image

ra1
Replication and Scale

How could we successfully replicate this solution elsewhere?

The Rainforest Alliance’s already developed training modules on this herbicide-free weed management system can be used in other tea-growing regions, especially in tropical conditions like those in Sri Lanka. As of today, the Rainforest Alliance and its partners have provided training on this system mostly in Sri Lanka and have begun training in India. Funding is required to build the structure to roll out the training for farmers and extension workers in more regions in India and elsewhere. The amount of funding required depends on an assessment of several factors, including the location and number of farmers who will receive training and technical assistance. Both smallholder organizations and companies that operate larger plantations can be key partners for replication. Tea sector associations can help support extension services and research institutions can help address research needs.

YouTube URL

Evangelists for Sustainable Tea Farming
Overview
Rare
© 2025 Rare.
  • Terms of Use
  • Privacy Policy
  • Contact
back to top