Farming Like the Incas

The Inca civilization grew a variety of crops in the Andes Mountains, despite the rough terrain and scant rainfall, using sophisticated agricultural methods developed over centuries. Those methods faded away when the conquistadors took over, partly because so many Incas died of war and disease, and also because the invaders insisted on doing things their own way. But the hillside terraces and irrigation systems used by ancient Incas were the most efficient way to grow crops in the Andes.

The terraces leveled the planting area, but they also had several unexpected advantages, Kendall discovered. The stone retaining walls heat up during the day and slowly release that heat to the soil as temperatures plunge at night, keeping sensitive plant roots warm during the sometimes frosty nights and expanding the growing season. And the terraces are extremely efficient at conserving scarce water from rain or irrigation canals, says Kendall. “We’ve excavated terraces, for example, six months after they’ve been irrigated, and they’re still damp inside. So if you have drought, they’re the best possible mechanism.” If the soil weren’t mixed with gravel, points out Kendall, “when it rained the water would log inside, and the soil would expand and it would push out the wall.” Kendall says that the Incan terraces are even today probably the most sophisticated in the world, as they build on knowledge developed over about 11,000 years of farming in the region.

The rainfall is still scant and the hills are still steep, and there is renewed interest in employing the ancient and diversified crops and the traditional ways of farming in the Andes. Read all about it at Smithsonian.