Ask a master gardener: Consider planting the Three Sisters — corn, beans and squash

I am just returning from a trip to North Dakota and while passing through South Dakota, we stopped at The Mitchell Prehistoric Indian Village, an archaeological dig site. As I read through the info in the museum, they mentioned the three crops the Indians used most as corn, beans and squash (pumpkin). I kept thinking they would refer to this group as the “The Three Sisters.” That is what it was called in my grandparents’ garden. But they never mentioned that familiar phrase.

Corn, beans and squash were the main agricultural crops of various Native American groups. When planted together in a companion planting method, they become what the Iroquois and other Native Americans called “The Three Sisters,” a gardening method which was passed on to the settlers.

The three crops benefit from each other. The corn provides a structure for the pole beans to climb, eliminating the need for poles. The beans provide the nitrogen to the soil that the other plants utilize (this actually takes a year to take effect), and the squash spreads along the ground, blocking the sunlight, helping prevent establishment of weeds. The squash leaves also act as a “living mulch,” helping to retain moisture in the soil, and the prickly hairs of the vine discourage pests. Corn lacks the amino acids lysine and tryptophan, which the human body needs to make proteins and niacin, but beans contain both and therefore corn and beans together provide a balanced diet.

If you would like to try this method here is how:

If you want to try to stay authentic and plant like the Native Americans, prepare the soil by adding fish scraps and wood ashes to increase fertility. I would probably stick with a good compost myself.

Make a mound of soil about a 8-10 inches high and 24 inches wide. The centers of your mounds should be about four feet apart and should have flattened tops. A block of at least four mounds will help with corn pollination. In the center of each mound, plant six or seven corn kernels in a small circle. When the corn is about five inches or so tall, plant seven or eight pole beans in a circle about six inches away from the corn plants. A week or so later, plant seven or eight squash or pumpkin seeds about a foot away from the beans, at the edge of the mound.

When the plants begin to grow, you will need to thin out all but a four or five of the strongest of the corn plants from each mound. Also, keep only about six of the hardiest of the pole beans and only two or three of the squash plants. You will have to do some weeding until the squash matures enough to take over for you.

Be sure to select plant varieties that will lend themselves to this method. You will need pole beans, not the bush type, and a variety of corn that has a tall stalk to avoid the beans overwhelming them. The squash or pumpkin should be the vining type, not the bush type. Be sure to read the seed descriptions when choosing the varieties.

I mentioned this method being in my grandparent’s garden but my dad did not carry on the tradition because he did not like “tiptoeing” through the squash to get to the corn and beans, although the Native Americans more than likely planted field corn or a variety which was left to dry in the field and then ground into meal.

Peter Sutter is a lifelong gardening enthusiast and a participant in the MU Extension’s Callaway County Master Gardener program. Gardening questions can be sent to [email protected].