Rice fields in Vietnam (ruộng or cánh đồng in Vietnamese) are the predominant land use in the valley of the Red River and the Mekong Delta. In the Red River Delta of northern Vietnam, control of seasonal riverine floodings is achieved by an extensive network of dykes which over the centuries total some 3000 km. In the Mekong Delta of southern Vietnam, there is an interlacing drainage and irrigation canal system that has become the symbol of this area. It jointly serves as transportation routes, allowing farmers to bring their produce to market. In Northwestern Vietnam, Thai people built their "valley culture" based on the cultivation of glutinous rice planted in upland fields, requiring terracing of the slopes.
The primary festival related to the agrarian cycle is "lễ hạ điền" (literally "descent into the fields") held as the start of the planting season in hope of a bountiful harvest. Traditionally, the event was officiated with much pomp. The monarch carried out the ritual plowing the first furrow while local dignitaries and farmers followed suit. Thổ địa (deities of the earth), thành hoàng làng (the village patron spirit), Thần Nông (god of agriculture), and thần lúa (god of rice plants) were all venerated with prayers and offerings.