The Three Sisters Technique

"A Three Sisters garden is usually a mound of soil with corn planted at the center. Beans ring the corn, and squash is planted at the edges. The corn stalks create a natural trellis for the beans to climb, while the beans fix nitrogen in the soil, which nourishes the corn. The leaves of the squash vines ramble around the mound, preventing the spread of weeds and providing shade for the shallow roots of the corn. The symbiotic interaction of the three plants allow them to produce more food using less water and fertilizer." - Earth Friendly Gardening

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