Staple Crops Cultivation in Thailand
Agricultural land accounts for around 41% of the total land area of Thailand or about 21 million
hectares [7]. Thailand is divided into five regions including North, Northeast, Central, East, and South
covering all 76 provinces. The cultivation patterns and water use by the staple crops in different
regions will be different depending on their respective geographical and climate conditions. Table 1
shows the planted areas of the ten studied crops classified by regions. Rice is grown nationwide and
has the largest plantation area covering around 70% of the plantation areas of the total ten studied
crops. Rice can be classified into two types, i.e., major and second rice. Major rice refers to the rice
grown during the wet season (i.e., May–October), while, the second rice refers to the rice grown in the
dry season (November–April). The largest major rice plantation areas are in the Northeastern region.
However, they do not have second rice due to the lack of irrigation system. Second rice is mainly
grown in the North and Central regions which are well irrigated. In addition, the Northeastern region is
also the main region for cultivation of field crops like cassava and sugarcane. Oil palm is widely
grown in the Southern region where the climate is rainy and humid. This region has about 86% of the
total oil palm plantation areas of the country. Figure 1 shows the actual cropping calendars for the
various crops in different regions of Thailand. This will be used for the calculation of crop water
requirement. The dry and wet seasons have been defined by the Royal Irrigation Department (RID) as
running from November through April and May through October, respectively.
Table 1. Plantation areas of the 10 studied crops classified by region