Creating a Three Sisters Garden

Creating a Three Sisters Garden Author: Sandy Vanno, Master Gardener Warren County CCE

Native peoples from different parts of North America have used a wide range of agricultural techniques. Perhaps the best known is the interplanting of corn, beans, and squash together – a trio often referred to as the “three sisters.” Planting these three native crops will help you become familiar with a crop management system practiced by the Iroquois people. By experimenting with an Iroquois garden, you will learn some basic plant breeding concepts and see how crops respond to being planted together. Also, you will learn the need for plant diversity and the importance of saving different plant species.

In three sisters planting, the three partners benefit one another. Corn provides support for beans. Beans, like other legumes, have bacteria living on the roots that help them absorb nitrogen from the air and convert the nitrogen to a form that plants can use. Corn, which requires a lot of nitrogen to grow, benefits most. The large, prickly squash leaves shade the soil, preventing weed growth, and, deter animal pests. The three sisters also complement each other nutritionally. The vines from the beans and squash can be left in the garden as compost.

Here are some guidelines for one type of setup:

  • Before you plant – conduct a soil test and prepare the garden site. Add compost or other materials such as peat moss or manure to the soil. This will improve the soil structure and add nutrients. If you have grown a green manure cover crop such as winter rye, turn it under two to three weeks before planting.
  • Plan and select a site – plant your three sisters' garden in late spring once the danger of frost has passed. The corn can be planted any time after the night temperatures are in the 50ºF range, but no later than June. Choose a site that has direct sunshine for most of the day (6-8 hours) and access to water.
  • Prepare the soil – break up and rake the soil. Build a mound about 12 inches high and between 18 inches and 3 feet in diameter. If you're in a dry area, flatten the top of the mound and make a shallow depression to keep water from running off.
  • Plant corn – soak four to seven corn seeds for several hours, but not more than eight hours before planting. Soaked seeds may dry out quickly, so keep the seeds well watered for the first week or two if the soil is not kept moist by rain showers. Plant the seeds about 6 inches apart in the center of the mound. You'll eventually thin to three or four seedlings. There are many corn varieties to choose from. Cornell recommends dent, flint, and flour corns, which are especially suited to this system.
  • Plant beans and squash – when the corn is at least 6 inches high, soak and then plant six pole bean seeds in a circle about 6 inches away from the corn. You'll eventually thin to three or four bean seedlings, leaving only the healthiest ones to produce. At about the same time, plant four squash or pumpkin seeds next to the mound, about a foot away from the beans, eventually thinning to one. Genuine Cornfield or Scarlet Runner bean and Connecticut Field or Small Sugar pumpkins are heirlooms, non-hybrid varieties that are readily available and recommended by Cornell. Most of the nitrogen converted by the beans will not be available to the corn and pumpkins the first year; the bean roots have to break down to release nitrogen. Corn is a heavy nitrogen feeder, so side-dressing with fertilizer is necessary to achieve satisfactory yields. You can use manure, compost, or commercial fertilizer.
  • Watering – your plants will need water each week. If it does not rain at least an inch per week, the planting will need to be irrigated. If you are using presoaked seed, remember to water more frequently at first.
  • Consider other additions – planting other traditional crops, such as sunflowers or Jerusalem artichokes around at the edge of the three sisters' garden. Put them on the north side so they won't shade your other plants.
  • Maintain your garden – as corn plants grow, weed gently around them and mound soil around the base of each stem for support. When the corn is knee-high and again when silks appear on the husks, “side dress” by putting a high nitrogen fertilizer (such as aged manure or fish emulsion) on the soil surface near each plant. To allow room for corn and beans to grow gently direct squash vines into walkways or garden edges. Once you observe young fruits, side-dress the squash plants with aged manure or compost, if you pinch off the tips of squash runners after several fruits have started to form, the plants will devote more energy to producing squash.
  • Harvesting and storage – harvest and store your corn, beans, and pumpkins with care. When the corn husks are dry, pick the ears and spread them out in a dry place. To prevent mold, do not store the ears when they are first harvested. If you plan to grind the corn, let it dry for several weeks; if you plan to save seed, choose seed from your most vigorous, uniform plants from the center of the ear. After you have shelled the kernels, keep them in a cool, dry place in covered containers or plastic bags. You can harvest your beans when they are green or after the pods have shriveled and dried. Pick pumpkins when their color changes.

If your outdoor growing space is limited, you can create a mini three sisters garden in an outdoor container, such as a barrel. Use a large container with holes or gravel in the bottom and fill it with potting mix and compost. Follow the above instructions, but plant only three corn seeds (and thin to 1) 2 bean seeds, and one mini pumpkin seed. Place the container where it will receive at least six hours of sunlight each day.



“The Three Sisters Garden”; Penn State Extension, Master Gardener Program, Pike County

“Creating a Three Sisters Garden”; University of Georgia Extension

“The Three Sisters: Exploring an Iroquois Garden”; Cornell CALS

“How to Plant the Three Sisters”; Cornell CALS

Last updated November 9, 2021