Cassava Cultivation in the Isan Region

Why Cassava Thrives in Isan

The Isan region of Northeast Thailand accounts for over 50% of the country's cassava production. Its sandy loam soils, distinct dry and wet seasons, and relatively flat terrain make it ideal for this hardy root crop. Cassava tolerates poor soil conditions that would stunt other crops, making it a reliable income source for smallholder farmers across the plateau.

Soil Preparation and Planting

Begin land preparation at the end of the dry season, typically March to April. Deep plowing to 25-30 cm breaks up compacted layers and improves root penetration. Follow with one or two passes of a disc harrow to create a fine, level seedbed.

Select healthy stem cuttings (stakes) from mature plants, 20-25 cm long with at least 5-7 nodes. Plant stakes at a 45-degree angle with two-thirds buried in the soil. Space rows 1 meter apart with 80 cm between plants for optimal yields.

Variety Selection

For the Isan region, consider these high-performing varieties:

• Kasetsart 50 (KU 50) — The most popular variety in Thailand, offering high starch content (25-28%) and good drought tolerance.
• Rayong 9 — Early maturing (8-10 months) with resistance to cassava mosaic disease.
• Rayong 11 — High yield potential with moderate starch content, well-suited for sandy soils.

Water and Fertilizer Management

Cassava is drought-tolerant but responds well to supplemental irrigation during the first 3 months after planting. Apply 15-15-15 NPK fertilizer at a rate of 50 kg per rai (6.25 tonnes per hectare) at planting, with a second application of potassium-rich fertilizer at 3-4 months to boost starch accumulation.

Harvest and Post-Harvest

Harvest at 10-12 months when starch content peaks. In Isan, the optimal harvest window is January through March. Roots must be processed within 48 hours of harvest to prevent deterioration. Most farmers sell to nearby starch mills, though direct marketing through platforms like FarmHand can increase margins by 15-25%.