The Three Sisters is a poly cropping technique developed by Ancient Native Americans that utilize the symbiotic characteristics between the Three Sisters that enhance each others growth and nourish the soil and the environment. The Three Sisters are Maize, Beans, and Squash. All three of these crops originated in central to northern Mexico around 10,000 years ago. It is such a successful system of growing these crops that it spread throughout modern United States and southern Canada. While I am not experienced in this technique, this article describes the technique as I researched it.
A Three Sisters planting is usually done in mounds that are about one foot high and two to four feet across, depending on which tradition you are subscribing to. The mounds are spaced about six feet apart. In each mound, corn, bean and squash are planted to create a symbiotic relationship. Sometimes a rich compost is added to the mound to get the plants off to a good start.
The first Sister that is planted is the corn seed. Around a one foot diameter circle in the center of the mound, plant 4 to 6 corn seeds. This supports a tall and strong support system for the second sister. The leaves funnel the water into the roots which create a shallow fibrous mat just below the soil surface. Plant the corn seeds as soon as the soil is 50* F (10* C). This gives the corn a head start to give it time to develop the strength to support the second Sister.
About 3 weeks after the corn is planted, after it reaches 6 to 12 inches tall, plant the second Sister, the beans. Plant 3 or 4 bean seeds around each corn stalk. The beans first growth will be a low growing mound. Later, it will send out long tendrils that will twine around the corn stalk, reaching towards the sky. The legume adds nitrogen to the soil, sends its roots down deep, and helps to stabilize the corn to protect it from the strong summer storms.
The third Sister, six squash seeds are planted around the perimeter of the mound at about one week after the beans are planted. The squash spreads out to protect the soil from erosion, shade the soil to conserve moisture, and suppress weed growth. The squash has prickly leaves and stems that deter the deer and raccoons.
If you have the space or a community garden, give it a try. You might be able to get more food that you expect from a smaller space, and in a way that is better for the environment.