How did annual flooding of the Indus River help farming?

The annual flooding of the Indus River was a critical natural mechanism that supported the agriculture of the Indus civilization. This flooding served a dual purpose: it simultaneously destroyed and fertilized the land, requiring the civilization to develop the skill to control these formidable waters.1

The floodplains provided a simple, effective means of farming without the need for complex irrigation, manuring, or extensive plowing. Farmers utilized the natural cycle of the river in two primary ways:2

• Post-inundation planting: Main cereal crops were sown at the end of the flood season on land that had recently emerged from the receding waters, allowing for a harvest in the spring.2
• Flood-season planting: Other crops were sown in embanked fields at the beginning of the floods, ensuring they received the necessary water during their growth cycle to be harvested in the autumn.2

By mastering these flood patterns, the civilization was able to sustain a large, well-nourished population and cultivate crops such as wheat, barley, peas, mustard, and sesame.12