Tidal wetland rices are cultivated during the wet season in scattered areas along the coastal plains of Bangladesh, India, Indonesia, Myanmar, Thailand, Vietnam, and West Africa. Tidal rices can tolerate submergence due to flash floods or tidal fluctuations. Salt-tolerant tidal rices are grown in areas where there is salt water intrusion from the sea. The soils are of various ages and are complex and diverse, particularly in river floodplain areas. Many of these alluvial sediments have undergone little soil formation.
Soil texture varies from medium to fine.
It is usually more coarse on natural levees and finer in depressions and back swamps. Although many soils are fertile, problem soils such as acid sulfate and saline soils occur, particularly near coasts. The cropping systems vary depending upon the time, depth, and duration of flooding. Rice is the only food crop that can be grown during the rainy season. Most rice varieties can survive complete submergence for only 3 or 4 days, but submergence-tolerant varieties can survive for about 12 days.