three-sister planting
n.— «Imitating a traditional Iroquois practice called “three-sister planting,” the farm plants corn, beans and squash together. The beans fix nitrogen into the soil that corn depletes while the corn’s stalk enables the bean plant to grow upward. Squash keeps both hydrated.» —“A Farm Grows In Brooklyn” by Gillian M. Kalson The Indypendent (New York City) June 8, 2007. (source: Double-Tongued Dictionary)