Companion planting is one of the fundamentals of permaculture and organic farming. It is the practice of placing different crops in close proximity of each other, so they will be mutually beneficial. One of the earliest examples of companion planting we have today is that of the Native American peoples, who planted corn and pole beans together. The cornstalk would become a trellis for the beans to climb up. With the addition of squash, they pioneered what became the Three Sisters technique.