Improving water use efficiency for shallot production in Soc Trang province
An important objective of the Impact Cluster project: “Transition towards sustainable shallot value chains in the Mekong Delta”, is to improve the water use efficiency of shallot production in Soc Trang province. By improving the water use efficiency, the amount of ground water extracted can be reduced, reducing the impact of ground water extraction on land subsidence in Soc Trang province. As part of the project activities, Can Tho University as implemented at 6 irrigation demonstration locations trials to compare various irrigation methods and the impact on shallot production and water use efficiency. Drip irrigation was identify as the best system in terms of yield, quality and water use efficiency. A reduction of > 40% in water used to irrigate shallots was achieved with better quality and yield. A nice article was published in Nong Nghiep Moi Truong newspaper about the irrigation trials and results. Enjoy ready this article below.
Soc Trang faced with the risk of declining groundwater resources, Vinh Chau farmers want to convert to drip irrigation to save water, reduce costs and improve crop yields.
Risk of groundwater depletion
The sandy land of Vinh Chau town (Soc Trang) province is a specialized farming place shallot the largest in the country with an annual area of up to 7,000 hectares. Irrigation water for production here is mainly exploited from groundwater. However, in the face of the effects of climate change and overexploitation, groundwater resources are seriously declining.

According to Dr. Dang Kieu Nhan – Director of Mekong Delta Development Research Institute (Can Tho University), groundwater in the Mekong Delta, it is not replenished in situ but originates from the Southeast and the Cambodian Delta with a very slow movement speed. Meanwhile, the increasing demand for groundwater for agricultural farming and domestic purposes makes the water replenishment insufficient to compensate for the quantity extracted, the, leads to the risk of depletion.
In Vinh Chau town, in the past, farmers only needed to drill wells at a certain depth, then place pipes and pump water for irrigation. However, now, with that same depth, the water is no longer enough to pump, forcing farmers to place pipes deeper, at the same time, it must be inflated down to create pressure to push water up.
According to Mr. Chau Van Thang –, Deputy Head of Agriculture and Environment Department of Vinh Chau town, every year during the local dry season, there is no water shortage because people find ways to get groundwater. Previously, people only needed to use one motor to absorb water, but now they have to use additional bellows to pump water at a depth of about 50m. If the water is still not enough, people increase the depth to 70 – 80m and use 2 more motors.

Due to sandy soil properties, digging water storage ponds in Vinh Chau is very difficult to do. Some households have adopted tarpaulin solutions to store water, but the amount of water stored is still very limited. This poses a big challenge for agricultural production, especially for farmers who grow shallot. Without effective irrigation water solutions, the risk of future shortages of produced water is very high.
Drip irrigation system outlook
In 2024, The Mekong Delta Development Research Institute cooperates with the Department of Agriculture and Environment of Vinh Chau town and a number of partners to implement the project to convert to the operating value chain sustainable purple in the Mekong Delta. The project, funded by the Dutch Enterprise Agency (RVO), lasts for 2 years. One of the project’s highlights is technical transfer drip irrigation add shallot.
This system is considered to have many advantages such as saving irrigation water; reduce labor costs; limit fertilizer loss; reduce the impact of wind and do not wet onion leaves… This helps farmers improve productivity compared to traditional hand irrigation methods.
This system uses mini swivels and drip wires from 12 – 15mm diameter, with about 3 – 4 drip wires/drip wires (depending on soil type). According to calculations by experts from the Mekong Delta Research and Development Institute, the total investment cost of drip irrigation system is about 8.2 million VND/ha, while the hand irrigation method costs about 11 million VND/ha (, installing machinery and labor irrigates). Thus, farmers can save nearly 2.8 million VND/ha when converting to this irrigation method.

Test results at several models in Vinh Chau town showed that the breed Vinh Chau shallot traditionally using hand irrigation, the yield is about 14.3 tons/ha. With the drip irrigation technique, onion yield increased to 15.1 tons/ha, offering great prospects.
Thach Son farmers in cluster 6, ward 1, Vinh Chau town are cultivating 2,000 square meters of shallot. Currently, his method of irrigating onion fields is mainly pumping from groundwater. On average, every month he has to spend around 700,000 VND in electricity to pump irrigation water, not including the cost of hiring workers.
In the dry season, the pumped water is very weak, causing many difficulties for production. Mr. Son rated: “Drip irrigation system is very suitable for family conditions because the investment cost is not too high, farmers are not extreme, have other working hours”.
Similarly, Mr. Huynh Xu Khang lives in group 6 together, ward 1 is planting 5,000m2 of shallot with 2 varieties of traditional Vinh Chau shallot and Maserati F1 shallot (a new experimental variety).
8 years ago, when testing plant Maserati F1 shallot, Mr. Khang continuously encountered failures due to improper irrigation techniques, causing onion leaves to be damaged and pathogens to arise.

However, since 2024, when applying the drip irrigation system transferred by the Mekong Delta Research and Development Institute, onion fields have shown positive results, and trees have grown evenly, the roots are deeply ingrained, limiting water stagnation on the leaves.
“The investment cost of drip irrigation system is not high. If hiring hand irrigation labor costs about 4 million VND/1,000m2, and investing in drip irrigation systems ranges from 2 – 3.5 million VND (installation supplies)”, Mr. Khang said.
Looking carefully at each onion bush, Mr. Thach Tien – member of Hoa Thanh Vegetable Cooperative (Hoa Thanh, Lac Hoa commune, Vinh Chau town) commented, when watering hands, observe that the surface of the field is standing, but using equipment to check the moisture in the soil is not enough. Besides, due to strong spray water pressure, onion leaves break, fall, and easily spread pathogens. At that time, even if farmers treated with plant protection products, they were also washed away by water, which was not effective.
According to Mr. Tien, applying the drip irrigation technique, onion leaves are not wet much, but the moisture in the soil is enough, and the plant grows well. In the next onion, he plans to install a drip irrigation system to save time, reduce costs, and help improve onion quality.
Besides the drip irrigation method, the introduction of new varieties of Maserati F1 shallot it is also bringing clear results to Vinh Chau farmers. According to Mr. Chau Ba Binh – technical officer of Fresh Studio, this onion variety has a longer growing time than the local variety of about 10 days, but yields 10 – 20% higher%.

The yield of Maserati F1 shallot grown by drip irrigation method is about 19.2 tons/ha, about 4.1 tons/ha higher than traditional purple onion varieties.
Furthermore, the onion quality was also significantly improved. Maserati F1 shallot for large tubers, beautiful color, suitable for consumer tastes, higher selling price than local purple onion from 1,000 – 2,000 VND/kg.
However, some farmers are concerned that growing new onion varieties could affect soil fertility in the long term. Crop rotation and rational use of fertilizers, therefore, farming techniques will be an important factor in ensuring the sustainable development of this model.
Shallot are the main crop of Vinh Chau town. Drip irrigation techniques not only help save water resources but also improve productivity, product quality and income for farmers. In the long term, for this model to be effective, there needs to be strong links between farmers, the, businesses and local authorities to ensure stable output and sustainable market development.
Source: https://nongnghiepmoitruong.vn/tuoi-nho-giot-de-ung-pho-nguy-co-can-kiet-nuoc-ngam-d741851.html
The impact cluster: “Transition towards sustainable shallot value chains in the Mekong Delta” is funded by The Netherlands Enterprise Agency (RVO) and consists of the following project partners:
- Bejo Zaden
- Groot & Slot
- Royal Brinkman
- BvB Substrates
- Eurofins
- Can Tho University
- Fresh Studio
Improving water use efficiency for shallot production in Soc Trang province.