Three Sisters farming: A model of Regenerative Agriculture

When early colonists observed Native American planting techniques, they noticed three crops often planted side by side: corn, beans, and squash. To European eyes, these mixed gardens appeared haphazard, but the Iroquois, Cherokee, and other Native American gardeners understood something the new settlers did not. When planted together, these crops help each other grow. Once harvested, each crop is easy to store, can be prepared in multiple ways, and lasts through the winter.

This method of companion planting is now known as “Three Sisters Gardening” and draws upon centuries of Native American agricultural knowledge and expertise. The crops complement each other both visually and nutritionally in two key ways: in the soil—through a mutualistic symbiotic relationship—and on the plate, by providing a balanced diet.

The tall stalks of corn provide a natural trellis for the climbing beans, preventing them from being overtaken by the sprawling squash vines. In return, beans help stabilize the corn during strong winds and enrich the soil with nitrogen. Beans host rhizobia on their roots, bacteria that convert atmospheric nitrogen into forms usable by plants—a process known as nitrogen fixation. Meanwhile, the broad leaves of squash shade the ground, preserving soil moisture and suppressing weeds.

Culinarily, a diet centered around corn, beans, and squash is nutritionally complete. Beans are high in protein and contain amino acids that corn lacks. Corn supplies carbohydrates, while squash contributes essential vitamins and minerals not present in the other two crops.

The term "Three Sisters" originated with the Haudenosaunee, also known as the Iroquois. In their traditional planting method, all three seeds are sown together in elevated mounds, which improve drainage and prevent waterlogging of the roots.

In drier regions, however, the crops are sometimes planted in separate fields with wider spacing to conserve water. Regardless of the method, each plant needs adequate space to thrive, and the garden must include enough of each crop to ensure effective pollination. Beans are self-pollinating, so even a single plant can produce. Squash, which relies on insect pollinators, benefits from having multiple plants blooming simultaneously. Corn is both wind-pollinated and self-pollinating, and most planting guides recommend at least 10–20 corn plants to achieve a good yield.

Various layouts for Three Sisters Gardens, including traditional Iroquois mounds and modern grid systems adapted for different climates, can be found online and in gardening books.

Because all three crops can be dried and stored for year-round use, they provided essential sustenance for Native American communities during harsh winters. While this consideration may be less critical today than it was three centuries ago, it is becoming increasingly relevant with the recent rise in personal gardening for food security and sovereignty.