There is one thing that distinguishes 60-year-old Vo Van Van's rice fields from a mosaic of thousands of other emerald fields across Long An province in southern Vietnam's Mekong Delta: It isn't entirely flooded.
That and the giant drone, its wingspan similar to that of an eagle, chuffing high above as it rains organic fertilizer onto the knee-high rice seedlings billowing below.
Using less water and using a drone to fertilize are new techniques that Van is trying and Vietnam hopes will help solve a paradox at the heart of growing rice: The finicky crop isn't just vulnerable to climate change but also contributes uniquely to it.
Rice must be grown separately from other crops and seedlings have to be individually planted in flooded fields; backbreaking, dirty work requiring a lot of labor and water that generates a lot of methane, a potent planet-warming gas that can trap more than 80-times more heat in the atmosphere in the short term than carbon dioxide.
It's a problem unique to growing rice, as inundated fields stop oxygen from entering the soil, creating the conditions for methane-producing bacteria. Rice paddies contribute 8% of all human-made methane in the atmosphere, according to a 2023 Food and Agriculture Organization report.
Vietnam is the world's third-largest rice exporter, and the staple importance to Vietnamese culture is palpable in the Mekong Delta. The fertile patchwork of green fields crisscrossed by silvery waterways has helped stave off famine since the Vietnam War ended in 1975. Rice isn't just the mainstay of most meals, it is considered a gift from the gods and continues to be venerated.
It is molded into noodles and sheets and fermented into wine. In busy markets, motorcyclists lug 10-kilogram (22-pound) bags to their homes. Barges haul mountains of the grain up and down the Mekong River. Rice kernels are then dried and hulled by machines before they're packed for sale in factories, lined from floor to ceiling with sacks of rice.
Van has been working with one of Vietnam's largest rice exporters, the Loc Troi Group, for the past two years and is using a different method of irrigation known as alternate wetting and drying, or AWD. This requires less water than traditional farming since his paddy fields aren't continuously submerged. They also produce less methane.
Using the drone to fertilize the crops saves on labor costs. With climate shocks pushing a migration to cities, Van said that it's harder to find people to work the farms. It also ensures precise amounts of fertilizers are applied. Too much fertilizer causes the soil to release Earth-warming nitrogen gases.
Once crops are harvested, Van no longer burns the rice stubble—a major cause of air pollution in Vietnam and in its neighbors, as well as Thailand and India. Instead, it's collected by the Loc Troi Group for sale to other companies that use it as livestock feed and for growing straw mushrooms, a popular addition to stir-fries.
Van benefits in various ways. His costs are down while his farm yield is the same. Using organic fertilizer enables him to sell to European markets where customers are willing to pay a premium for organic rice. Best of all, he has time to tend to his own garden.
"I am growing jackfruit and coconut," he said.
Loc Troi Group CEO Nguyen Duy Thuan said that those methods enable farmers to use 40% less rice seed and 30% less water. Costs for pesticides, fertilizer and labor also are lower. Thuan said Loc Troi—which exports to more than 40 countries including in Europe, Africa, the United States and Japan—is working with farmers to expand acreage using its methods from the current 100 hectares to 300,000 hectares.