In Thac Ba commune, Lao Cai province, northern Vietnam, Nguyen Trong Hieu, a farmer in his 60s who quit timber production and pig farming, earned income of just under about 200 million VND in 2025 from 3 hectares of four-season lime (local name chanh tu quy). The local paper Dan Viet reported it on 28 July 2026. Choosing a variety that flowers and fruits year-round, he harvests roughly 20 tonnes a year. For Japanese food and beverage manufacturers, this small switch offers concrete material for the question of from which origin and when to draw acidic-citrus raw material. The yen conversion is shown as an approximation using a guide of 1 yen = about 170 VND.<\/p>\n
Mr. Hieu's farmland totals roughly 4 hectares. Of that, he has planted four-season lime on 3 hectares and grows tea (che) on the remaining 1 hectare. Due to administrative-division reorganization it is now Thac Ba commune, Lao Cai province, but it was previously mountain land corresponding to Da Coc village, Yen Binh district, former Yen Bai province. He once made a living from acacia (keo) for afforestation and pig farming, but he stopped the pig farming and switched the poor slopes to citrus.<\/p>\n
The four-season lime is a small fruit with almost no seeds and abundant juice, staying at about 1-2 meters in tree height. As the name suggests, it repeats flowering and fruiting through all four seasons, so the harvest is not skewed to a particular period. In Vietnam the seedling line is said to be of California origin, and the quickness of beginning to bear about one year from planting is also a feature. Mr. Hieu obtained seedlings from a Hanoi agricultural research institute (Vien Nong nghiep I) and trained the trees by grafting onto old pomelo (buoi) stock as rootstock. This procedure of using an existing root system is thought to have helped them take in the mountains.<\/p>\n
The move to lift income by replacing poor land with high-return crops is happening simultaneously in various parts of the north. In Hue, farmers who converted hard-to-use, low-lying wet paddy to lotus annual income equivalent to 3-5 times that of rice farming<\/a> are reported to have reached, and Mr. Hieu's citrus switch is easier to understand when placed in this flow. What they share is that, having acknowledged the land's weakness, they reselected a crop that fetches a price precisely on that land.<\/p>\n Mr. Hieu's four-season lime stays at a normal-season farmgate price of 8,000-10,000 VND per kg (roughly 47-59 yen). Even so, by averaging the harvest of 20 tonnes a year across the whole year, he made income of just under about 200 million VND (just under about 1.2 million yen) in 2025. Prices jump around Tet (Lunar New Year), rising to 40,000-50,000 VND (roughly 235-294 yen) in the demand season, and the market at the time of reporting was also at 25,000-30,000 VND (roughly 147-176 yen), about three times the normal season.<\/p>\nEven at 8,000 VND\/kg, 20 tonnes a year: filling the price trough with volume and year-round supply<\/h2>\n