How did the Three Sisters Growing method work?

Answer 1

This is a phrase for a type of companion planting that was used in many places in the Americas. The beans provide nitrogen to the soil that is used by other plants. Beans fix nitrogen with a symbiotic bacteria called Rhizobia within nodules in their root systems. The corn (maize) provides a structure for the beans to climb so poles are not needed. The squash shades the ground and helps moisture stay in the soil and the little hairs on the leaves keep away insects. Corn does not have the amino acids lysine and tryptophan, which the human body needs to make proteins and niacin, but beans contain both and therefore corn and beans together provide a balanced diet. In the Southwest a fourth plant, rocky mountain bee plant, was added to attract bees to help pollinate. It's seeds and leaves were eaten as a vegetable. It was also used a medicine and a dye stuff for a black dye.

The Hopi usually planted very deep in sandy soil in areas where it would receive runoff from the mesas. The sand acted as a kind of mulch.