How To Grow A Three Sisters Garden

Corn, beans, and squash: North America’s most successful companion planting trio for 6,000 years!

April 27, 2017
three sisters garden
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As the first humans became established in the Americas, they discovered dozens of our familiar staple foods growing in the wild, at which point they started collecting seeds and planting them in gardens. Seed for the most useful food plants traveled along trading routes. As plants were grown, and the most successful ones were replanted and shared, hundreds of new and unique varieties suited to local climates were created—a process that was repeated again and again until the crops reached every corner of the continent.

The most notable of these shared crops in North America were corn, beans, and squash: three plants that seemed to grow better together than apart, (here are 26 other plants you should always grown side-by-side) and to be a more sustaining food for humans when eaten together than alone.

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Together, they became known as the "three sisters," and by about 4,000 BC they were claiming top billing in gardens, store rooms, cooking vessels, and even in religious ceremonies (as gifts from the supernatural) throughout the continent.

Here, we explain the mutually beneficial relationship between these plants and how you can plant your own three sisters garden. 

(Whether you're starting your first garden or switching to organic, Rodale’s Basic Organic Gardening has all the answers and advice you need—get your copy today!)

How The Three Sisters Help Each Other Out

Planted together, the tall, sturdy corn stalks provide support for the slender climbing bean vines, helping the beans spread their leaves toward the sun; the nitrogen-fixing bacteria associated with the beans' roots pull nitrogen out of the air and share some of it with the hungry corn’s roots; and the huge leaves of the squash vines shade the ground, acting as a living mulch to keep weeds down and conserve moisture for all three crops.

Related: 7 Secrets For A High-Yield Vegetable Garden, Even When You're Tight On Space

Additionally, bean leaves have sharp hairs which trap some insect pests, and the spiny vines and leaves of squash help to deter four-legged animals from venturing into the patch to sample the tempting corn. (Here are 5 totally humane ways to keep deer out of your garden.)

 

Why They're Better Eaten Together

Early Native Americans found that eating corn, beans, and squash together promoted health. Nutritionists have only recently explained why: They are all rich in vitamins, minerals, complex carbohydrates, essential fatty acids. But most importantly, when eaten together, the corn and the beans contain all essential amino acids in the amounts required to make up a complete protein

Related: 8 Foods You Should Always Eat Together

How To Plant Your Own Three Sisters Garden

The three sisters are usually planted in “hills,” or small groups of plants, and those groups are spaced some distance from each other, leaving empty space between them where the squash can spread. In climates with regular summer rains, the hills may be shaped into raised mounds (for better drainage in wet soil), or even just level soil spaced 2 ½ to 3 feet apart.

In dry climates, try shaping hills into shallow depressions, so they can better catch and absorb water. (These will need to be spaced 4 to 6 feet apart to allow each plant’s roots to gather water from a larger area.)

Arrange your hills in a block, rather than in a long single row, for better pollination.

For more specific details on traditional three sister designs for different climates, check out this article on Native American traditional gardens, starting about half-way down the page.

Related: 14 Plants You Should Never Grow Side-By-Side

Choosing Varieties

For a traditional three sisters garden, select heirloom varieties of corn, pole beans, and winter squash that are adapted to your climate. A few years ago in my Pennsylvania garden, I planted a three sisters garden featuring impressive 10-foot-tall 'Cherokee Gourdseed' corn (for cornmeal), 'Cherokee Cornfield' pole beans (for dry beans), and Seminole pumpkins—all heirlooms that have been grown for hundreds, if not thousands, of years in the Eastern U.S. However, a combination of sweet corn, tender stringless green beans, and zucchini would work just as well. 

 

When To Plant

Plant the corn seeds first, planting 3 (or more) seeds, spaced about 6 inches apart, in each hill. In areas with regular rain (or irrigation), plant seeds about 1 inch deep; in dry areas seeds may be planted up to 4 inches deep. Knowing when it’s safe to plant tender crops like corn can be challenging, especially as the weather becomes more variable, but your local wild plants can help: Old timers say it’s safe to plant corn when the oak leaves are bigger than squirrels’ ears (which, if I had to guess, are maybe ¾ of an inch long). 

Related: Why You Should Always Plant Flowers In Your Vegetable Patch

Plant beans and squash seeds next, a couple of weeks later, when your corn plants are about 6 inches tall. Plant 2 or 3 bean seeds about 6 inches from the base of each corn plant. Plant squash in their own hills about halfway between the hills of corn and beans. Plant 2 or 3 squash seeds, spaced about 6 inches apart, per hill. Use mulch or a hoe to keep the weeds down until the squash vines cover the garden—they will effectively prevent more weeds from starting.