From rice straw to potato fields: Vietnam connects crop rotations, composting and regional learning

By Lukie Pieterse, Editor and Publisher, Potato News Today

A field exchange in northern Vietnam has brought renewed attention to the role potatoes can play within diversified farming systems that connect crop production, nutrient management and local markets.

Participants in a regional roots-and-tubers workshop visited Nam Cuong Agricultural Production, Business and Service Cooperative in Ninh Binh on October 1. An account published by CGIAR on October 6 described discussions involving rice production, straw composting and potato farming.

The exchange formed part of a workshop organised by the International Potato Center and a wider effort to develop regional learning relationships. At the cooperative, visitors encountered an operating system in which the decisions made for one crop affect the opportunities available for another.

For the potato industry, that makes the example worth examining. The crop is being considered within a production calendar, a nutrient-management system and a cooperative business.

The question is how those connections can support farmers’ livelihoods while improving the use of the resources available to them.

The cooperative provides a practical setting

A March 2026 account by IRRI and CIP researchers described Nam Cuong as involving approximately 1,600 farming households managing around 300 hectares, including 130 hectares devoted to potatoes.

The account outlined a cropping cycle incorporating a four-month peanut crop, a three-month rice crop and a three-month potato crop. It also identified an objective of supplying produce to feeding programmes across 20 local schools.

Those figures describe the cooperative’s reported system and ambitions. They should not be read as national statistics or confirmation that every intended supply arrangement has been completed.

The scale nevertheless gives the field exchange a useful setting. Participants could discuss farming practices within an organisation coordinating numerous households and several production activities. That matters because agricultural technologies operate within relationships. Equipment needs operators, crops need markets and shared facilities need workable arrangements for access and payment.

The cooperative offers a place where those questions can be addressed alongside the agronomy. Its value as a learning site lies in the ability to examine how the different parts fit together.

The cropping calendar determines what is possible

Introducing potatoes into a rice-based system involves more than identifying a suitable variety. The crop needs to fit the available season, and the activities surrounding it must be organised around that window. Land preparation, planting material, crop management and harvesting all affect whether the next stage of the rotation can proceed.

The Nam Cuong example therefore encourages attention to the complete calendar. A practice may be useful for one crop while creating a timing problem for the next. This is particularly relevant to the handling of crop residues. Rice straw becomes available at harvest, but converting it into a useful input takes time and work.

For a farmer, the important question is whether the material is ready when it is needed. A technically effective process has limited value if it cannot fit the production schedule.

The potato opportunity is consequently linked with the management of the preceding crop. That connection helps explain why rice and potato researchers are working together on the system.

Mechanised composting addresses a specific timing problem

The composting work has a documented history. IRRI reported that a mechanised compost turner was handed over to Nam Cuong Cooperative during a training and demonstration event in August 2024. The activity took place under the Fertilize Right project.

The technical explanation described a process that could reduce decomposition time from about 90 days to 45 days compared with traditional methods. It also emphasised regular mixing and monitoring of conditions such as temperature and acidity. These are reported characteristics of the demonstrated process, not a guarantee that every composting operation will achieve the same result.

Their relevance to potato production is practical. A shorter preparation period can make the material easier to fit into a narrow interval between crops. The machinery also creates responsibilities. Someone must arrange the material, operate the equipment, monitor the process and determine when the resulting product is suitable for use.

The intervention therefore combines equipment with training. The machine contributes to the process, while the quality of the outcome depends on how the work is managed.

Rice straw becomes an input requiring careful assessment

The central idea is to turn a crop residue into material that can be used elsewhere in the farming system. That is a promising direction, but the useful measure is what the finished compost contributes under local conditions. Farmers need to understand its quality, nutrient contribution and cost of preparation and application.

Compost should therefore be considered within a nutrient-management plan. Its use does not automatically establish that all other fertiliser requirements have been met.

The wider Fertilize Right programme was launched in 2024 with objectives including improved fertiliser use, farmer incomes and lower greenhouse-gas emissions in rice cultivation. IRRI describes the programme through the four principles of nutrient management: appropriate source, rate, timing and placement. Those principles provide a framework for assessing the contribution of recycled material. They also help prevent a useful circular-economy idea from becoming a blanket recommendation.

For potato growers, the practical task is to connect the material’s characteristics with the crop’s needs and the conditions of the field. That requires information as well as access to compost.

Rice management remains part of the potato story

The October exchange also included discussion of mechanised direct-seeded rice combined with fertiliser deep placement. IRRI’s technical reporting presents this as a package bringing together planting equipment, nutrient placement, training and cooperative participation.

Its presence in a roots-and-tubers exchange is relevant because the system’s performance depends on more than the potato season. Decisions during rice production influence the timing of operations and the material available afterwards.

For a diversified farm, improvements need to be assessed across that sequence. A change that helps one crop should also be examined for its effect on the rest of the calendar. This gives the partnership between rice and potato specialists a clear purpose. Each brings knowledge of a crop, while farmers manage the transitions between them.

The useful outcome is a system that households can operate reliably. That includes the practical details of access to machinery, the timing of labour and the availability of technical support when conditions change.

Seed supply remains a separate requirement

At the October visit, cooperative director Nguyen Van Du discussed experiences involving seed-potato imports, variety selection and community-based cold storage. Those subjects underline a basic point: better management of local residues does not remove the need for suitable planting material.

A potato crop still depends on seed arriving in an appropriate condition and at a useful time. Variety selection also needs to reflect the available season and the intended market.

Shared storage can contribute to that arrangement, but a facility needs operating procedures and a clear purpose. Members need to understand how material is received, identified, held and withdrawn.

These are commercial and organisational questions as well as technical ones.

For visitors considering whether a similar approach might work elsewhere, the seed system deserves as much attention as the visible machinery. A cropping opportunity can be difficult to realise if the required planting material is unavailable when the land is ready.

The cooperative’s experience provides a basis for discussing that connection.

Earlier breeding work provides important background

Vietnam’s potato development also includes work on varieties adapted to local conditions.

In November 2023, CIP announced HCIP210 through a public–private collaboration with HZPC under the TAP5 project. The initiative brought breeding and selection work together with the objective of developing tropically adapted varieties. Vietpo’s published information describes HCIP210 as maturing in approximately 90–95 days. That is a supplier specification, rather than a universal prediction for every growing environment.

The variety provides an example of the breeding work behind efforts to fit potatoes into demanding production calendars. The October field-exchange account does not establish that HCIP210 is the variety grown throughout Nam Cuong’s potato area.

The broader connection is straightforward. A crop intended for a limited seasonal window needs material that can perform within it and produce something the market will accept.

Breeding contributes options. Their practical usefulness is established through local production, seed availability and customer response.

Regional learning brings shared problems into the same discussion

The wider workshop ran from September 28 to October 2, with activities in Da Lat and Hanoi. The CGIAR Capacity Sharing Accelerator’s account describes the launch of a Regional Learning Platform on Roots and Tubers, involving CIP and participating research organisations.

Topics included seed production, apical rooted cuttings, breeding, postharvest management and rice–potato systems. The programme combined technical discussion with opportunities to observe practices in Vietnam. That breadth is useful because potato-sector constraints rarely occur in isolation. A country may have promising varieties but limited multiplication capacity, or suitable production conditions but weaknesses in storage and market access.

A regional platform can help participants compare those constraints and identify where another organisation’s experience is relevant.

The important work continues after the visit. Participants need a way to follow up, exchange material or information where appropriate, and test ideas under their own conditions. A field exchange creates contacts and questions. Its lasting contribution depends on what those relationships enable next.

Farmers’ returns determine whether a system lasts

The March account of Nam Cuong reported potatoes as an attractive income-generating crop within the local rotation. That gives the development a clear commercial purpose, although the published information does not provide a complete, independently audited comparison of all costs and risks.

For farmers considering a change, the relevant calculation includes seed, labour, machinery, crop inputs, handling and the price actually received. The economics of composting also need to account for collection, processing, storage and application. Those costs can be organised differently within a cooperative than on an individual farm. Shared equipment may improve access, but members still need an arrangement that covers operating expenses and responsibilities.

The same applies to shared marketing or storage. A collective system works when its benefits and costs are understandable to the people using it.

The farmers’ perspective therefore belongs at the centre of the evaluation. A technically interesting rotation needs to support a livelihood that households can sustain.

Climate claims need evidence across the system

The researchers describe the work as part of an effort towards lower-emission and more resilient farming. The October field visit, however, does not provide a complete greenhouse-gas assessment of Nam Cuong’s rotation. It should not be used to assign a quantified emissions reduction to the whole system.

Evaluating that outcome would require attention to the relevant activities and boundaries of the comparison. Changes in residue handling, fertiliser use, machinery and crop production all need to be considered.

The same discipline applies to resilience. A more diverse calendar may create opportunities, but its performance needs to be examined through actual seasons, including difficult ones.

This does not diminish the value of the work. It clarifies what the current reporting demonstrates: a practical system under development, with identifiable technologies, participating farmers and questions that can be investigated.

For the potato industry, that is a useful basis for learning and further assessment.

The value lies in connecting the parts

Vietnam’s recent exchange offers a concrete example of potatoes being developed within a wider farming system. The work connects a crop calendar with seed supply, compost preparation, rice management, cooperative organisation and markets. Each part affects what the others can deliver. That is the practical lesson for potato professionals elsewhere. A promising intervention needs to be considered within the operation that will use it.

The next evidence to watch will include repeat-season performance, the costs of running shared services and the ability to maintain dependable seed and market arrangements. Those results will help show where the approach is useful and what adaptations are needed.

The farmers and researchers at Nam Cuong have provided a setting in which those questions can be discussed together. The regional platform offers a route for continuing the exchange.

For a crop with an increasingly important role in diversified food systems, that combination of practical experience and sustained collaboration deserves attention.