In the Luong Tam area of Can Tho city in southern Vietnam, more than 180 households and about 250 hectares are taking on "tom-lua (shrimp-rice)," using paddy fields as-is as shrimp-farming ponds. The stage is the outside of the dikes that keep out salt damage, land where in the dry season salt water enters and rice yields fall. It uses that salt water not as a defect but as a resource, raising rice and shrimp in turn in a single field. When Japanese food makers and restaurants look for sustainable shrimp-sourcing destinations in place of domestic, such low-input origins become candidates that cannot be ignored.
180 households and 250 ha outside the dikes, diverting the dry-season salt water to shrimp farming
According to local origin information, the farmers taking part in tom-lua in the Luong Tam area number over 180 households, and the farming area reaches about 250 hectares. The administration planned a 50-hectare expansion in 2026, and the result exceeded the target at 51.8 hectares (achievement rate 103%). The shrimp raised are three species—black tiger (tom su), whiteleg (tom the), and giant freshwater prawn (tom cang xanh)—switched by species to match the field's water quality and season.
As a concrete example of earnings, Nguyen Thi Oanh, a local, is introduced as having earned a profit of about 50 million–60 million dong last year after deducting expenses. Converting at a guide of 1 yen = about 170 dong, that corresponds to roughly 300,000–350,000 yen (a figure for one household, one season). The point is that on land in poor condition outside the dikes, she creates a side income hard to produce with rice alone. The administration backs the launch with inspection tours, technical training, and technology transfer, plus support for seed and materials and the dispatch of technical staff.
Shrimp that cannot use pesticides, as a result, produce 'rice close to organic'
Tom-lua's compatibility with the environment is a matter of mechanism, not a slogan. Because you raise shrimp in the same field, strong use of pesticides or insecticides kills the shrimp. So farmers are driven to a choice of using chemicals as little as possible, and as a result the rice too is grown with low pesticides. Research in the Mekong Delta has also organized that this constraint of "you can't use chemicals because the shrimp are there" brings the rice practically close to pesticide-free, leading to a push-up in unit price and demand. The cycle of shrimp in the salt-water period and rice in the fresh-water period also resets salinity and disease just by swapping the water, making it easier to avoid replant failure.
In Thanh Hoa province there is a case that raised the income of the same land 1.5–3-fold by mixing giant freshwater prawns in paddy fields, and the idea of making aquaculture and rice cultivation coexist in one field is not limited to the Mekong Delta. Giant freshwater prawns co-cultured in Thanh Hoa's paddies raise the value of the same land 1.5–3 times Read side by side with it, you can see that Luong Tam's effort is not a special case but one of the adaptation measures occurring simultaneously in many places across Vietnam.
Within the Mekong Delta's roughly 210,000 ha, Can Tho is positioned as a 'late starter with room to grow'
Tom-lua itself had spread across the whole Mekong Delta to about 219,000 hectares as of 2020, with the main producing areas being Kien Giang (about 100,000 ha), Bac Lieu (about 58,000 ha), Ca Mau (about 38,000 ha), and Soc Trang (about 9,700 ha). Can Tho's (old Hau Giang region) 250 hectares is still small in scale, but has large room to grow in that it is newly taking in salt-damaged land outside the dikes. Organizing each origin's position gives the following.
| Growing region | Guide to tom-lua area | Characteristics |
|---|---|---|
| Kien Giang | About 100,000 ha | The Mekong Delta's largest concentration |
| Bac Lieu | About 58,000 ha | Close to processing and export companies |
| Ca Mau | About 38,000 ha | Ahead in organic certification of mangrove shrimp |
| Soc Trang | About 9,700 ha | Deep experience of salt-water management on the coast |
| Can Tho (old Hau Giang) | About 250 ha | Newly opening up salt-damaged land outside the dikes, expanding with administrative support |
In Ca Mau province, a move is advancing that accepts salt damage as a premise rather than fixing it, creating added value with salt-tolerant crops and low-emission shrimp. This idea of treating salt damage as an industrial condition rather than a disaster is contiguous with Luong Tam's effort. Don't fix the salt: Ca Mau's salt-tolerant farming gives rise to the business opportunity of "plant salt" is also worth viewing together.
What Japanese procurement looks at is the 'path to certification'—Ca Mau's Naturland track record is the groundwork
Here is the main point for Japanese food and restaurants. Vietnam is the world's third-largest shrimp exporter after India and Ecuador, and Japan is a major export destination alongside the US, the EU, China, and South Korea. The reason Japanese buyers take interest in low-input tom-lua is not cheap unit price but "whether a third party can prove the low environmental load."
That receptacle already exists on the Vietnamese side. In Ca Mau province, mangrove shrimp has a track record of obtaining organic certifications such as Germany's Naturland, EU Organic, and Bio Suisse since the 2000s, and the major firm Minh Phu has set out a policy of pursuing ASC, BAP, and organic certifications for tom-lua. Moves to build low-emission shrimp into origins are also beginning in various places, and EU and NGO, 42 months: will Ca Mau's "low-emission shrimp" become proof for procurement? as covered in, the very mechanism of proof is becoming procurement value. Luong Tam's 250 hectares does not currently hold up organic certification, but a production structure where pesticides are hard to use is not inconsistent with obtaining certification. What the Japanese side should look at is not "is it already organic" but "is the path to certification realistic."
From salt-damaged land to adaptation, then to opportunity—the time axis Luong Tam follows
Luong Tam's path lies on a flow of time in which the constraint of salt damage is reread as an industrial condition. What was once a disaster—dry-season salt water cutting rice yields—turned, by diverting that salt water to a shrimp resource, the disadvantaged land outside the dikes into land producing side income. Next in line is the stage of whether a production structure where pesticides are hard to use can be connected to third-party certification such as ASC, BAP, or organic. As Ca Mau's mangrove shrimp has built up Naturland and EU Organic, once the mechanism of proof is in place, even a small origin of 250 hectares has room to reach Japanese shelves as "shrimp whose low environmental load can be explained." The premise then is that salt-water-period shrimp and fresh-water-period rice turn without a break year-round, and that the volume and size of black tiger, whiteleg, and freshwater prawn have a clear outlook. For domestically oriented restaurants seeking shrimp with a story even in small volume, and for food makers wanting to emphasize environmental care, Luong Tam becoming a realistic candidate is a matter for the road ahead. Whether the climatic constraint of salt damage can be turned, as-is, into differentiation material for the procurement side is the dividing line.
