For over 1000 years families have been using techniques that allow growing corn, beans and winter squash harmoniously in the same garden plot. Imagine being able to walk into your garden and harvesting all three!
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Check PriceThe Three Sisters garden show cases one of the greatest agricultural innovations in human history. The indigenous peoples of North America, designed a system of companion planting that is far more advanced than just three different vegetables planted together. Instead, they designed a living ecosystem in which each plant provides unique benefits that help the other plants thrive.
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The Mechanics Behind the Three Sisters Partnership
There is an actual scientific reason why corn, beans, and squash grow well together in a garden. Corn grows tall and gives beans a place to climb. Beans need to climb in order to not crowd the space on the ground and become susceptible to pests and diseases.
Beans act as factories that produce nitrogen for the soil. Certain bacteria that live within the roots of the beans capture nitrogen from the atmosphere and transform it into nutrients which the plants use. As the beans grow, the fertilizer that is created naturally by the beans nourishes the heavy feeding corn and squash, thus eliminating the need for any synthetic fertilizers.
Squash adds to the trio of plants by reaching out with its broad large leaves, spreading over the soil surface. As part of the living mulch system, the squash shields the soil from the sun, preventing the germination of weeds and retaining moisture in the soil. Prickly squash leaves and stems aid in the creation of barriers that deter common garden pests, such as raccoons and other rodents.
Ideal Preparation of Soil for Success
Before planting, rich, loose, well-draining soil to a depth of 4-6 inches should be added to the mounds. The Three Sisters method begins with a firm foundation. Over good soil, mounds should be constructed of soil compressed into mounds 18 inches wide and 4 to 6 inches tall. Mounds should be placed about 3 feet apart for best results.
Before planting, add some compost or aged manure to each mound. Corn and squash are heavy feeders so they will need to nutrients. Additionally, improved soil structure helps bean roots establish their nitrogen-fixing partnerships more effectively. You should check your soil pH, as these crops will do best in the slightly acidic to neutral range of 6.0-7.0.
The Timing of Your Three Sisters Planting
When planting your Three Sisters garden, it's important to pay close attention to timing. To get started, you should begin your corn planting once the soil consistently reaches 60°F. You should plant around 4 to 6 corn seeds in the center of each mound and space the seeds 6 inches apart in a circle. This will give you extras in case some fail to germinate, and later you can thin down to 3 or 4 of the strongest seedlings.
After 2 to 3 weeks of planting corn, you can plant beans. This time is needed so that the corn can grow taller stalks that will support the beans. When you plant beans, make sure you plant 4-6 beans around the corn, spacing them 6 inches away from the corn.
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Plant squash seeds one week after the beans. Plant 2-3 squash seeds towards the outer edge of each mound, making sure there is enough space for the vines to spread out without crowding the corn and beans.
Selectiing the Correct Varieties of Three Sisters
Not all varieties of corn, beans and squash perform well in the Three Sisters planting system. For corn, go with the sturdy, tall varieties like dent corn or flint corn. You want something that has strong stalks that can support the weight of the bean vines. Sweet corn will work, but it may require added support stakes since it is usually shorter and not as robust.
Choose pole bean varieties rather than bush bean types. Lima beans, runner beans, and pole green beans are all good choices. These enthusiastic climbers will spiral up your corn stalks, so pick beans that are moderate for their class and not overly aggressive climbers that will knock over the corn.
When it comes to squash for the winter, the best varieties are acorn, butternut, and hubbard. These can be stored for months after harvesting. Summer squash can be planted as well, but they need to be harvested often and do not offer the same long term food storage benefits that make this system historically valuable.
Managing Water and Nutrients
The Three Sisters garden needs consistent moisture, but constant irrigation will result in trouble. Deep watering is preferred over frequent shallow watering, and weekly watering is better than daily watering. Watering should be done around the base of the mounds as opposed to overhead which could lead to the development of fungal diseases.
This system's beauty comes from its self-sufficiency. Beans supply nitrogen, corn provides structure, and squash saves moisture and controls weeds. However, it is possible to enhance production by applying compost tea every 3-4 weeks during the growing season.
Common Problems and How to Fix Them With the Three Sisters
If beans overpower your corn and cause stalks to bend or break, you planted too many bean seeds or picked overly vigorous varieties. Thin beans to 2-3 plants per mound. If necessary, provide supplemental support with stakes.
When squash vines grow too aggressively and shade out other plants, guide them to grow away from the center of the mound. Take care to re-direct wandering vines and prune excessive foliage that blocks the light from reaching the corn and beans.
If your seeds are germinating poorly, there is a good chance that you have problems with soil temperature or that you are planting them too soon. Make sure the soil is warm enough, and if your growing season is limited, you may want to start your seeds indoors.
Getting the Most Out of Your Three Sisters Crop
To help with your harvest time frame, try staggering the planting times. In order for consistent production of vegetables into the fall, you should plant new Three Sisters mounds every two to three weeks until the early summer.
Different crops require different harvest timings. Continue harvesting green beans in the summer to promote continued growth. When sweet corn is ready to be harvested, the kernels will be filled and have a milky substance. Winter squash should be left on the vine to cure until the stems dry, and you cannot press down the skin with your fingernail.
Three Sisters Garden demonstrates the agricultural knowledge that First Nations People possess, while also teaching us how to solve our current issues surrounding food production. Three Sisters Garden is a simple system that requires little labor, no manmade farming products, and generates large yields from small areas. Learning from those who mastered sustainable gardening for centuries, you can establish a flourishing, self-sustaining garden that supplies food for your family while respecting traditional ecological knowledge.
