Which crops formed the foundation of agriculture in Mesoamerica?

The foundation of agriculture in Mesoamerica was centered on three primary crops: corn (maize), beans, and squashes. Often referred to as the "Three Sisters" in various Indigenous traditions, these plants were frequently grown together in a symbiotic interplanting system known as milpa.12

This agricultural system was highly effective:
* Corn provided the primary source of calories for Mesoamerican populations.1
* Beans acted as a natural fertilizer by fixing nitrogen in the soil, which benefited the other crops.2
* Squash served as a ground cover, with its large leaves retaining soil moisture and suppressing weeds.2

While these three crops formed the core of the diet, other important domesticated plants in the region included chili peppers, cotton, avocados, cacao, manioc, and tomatoes. The development of these crops allowed for the transition from nomadic hunting-gathering to the establishment of permanent villages and, eventually, the rise of complex civilizations like the Olmec, Maya, and Aztec.31