Introduction
The three sisters gardening method is a means of inter-planting three plants (corn, beans, and squash) within close proximity to each other. It is a form of companion planting (planting different species of plants together for an increased benefit such as insect habitat, improved pollination, fertilizer, reduced disease/plant damage, etc.). The three sisters method is an ancient agricultural method first developed by Native Americans across North America. Different regions selected for certain traits and crop varieties based on yield and ability to thrive in a region or climate. Overtime selective breeding allowed for various corn, bean, and squash varieties to be developed, some of which specialize in drought resistance, disease resistance, and pest resistance.
In respect to the name the first and oldest sister, corn, is meant to grow first and create support for the second sister. Then, once the corn is about four to six inches tall you plant the pole beans next to the corn. The beans rely on the corn stalk as a trellis to be able to grow up and out to capture more sun. Beans (legumes) also have a mutualistic relationship (when two organisms co-evolve together and benefit each other) with nitrogen fixing bacteria known as rhizobia which attach to the roots of the beans and make nitrogen available for the plant that season, while also allowing for said nitrogen to be put back into the soil for the next growing season when the roots decay underground. While planting the beans you also plant the third sister, squash which helps protect the soil from extreme heat/water loss and shades out any unwanted weeds/competition.
There are various methods in which Native Americans grew their three sisters plots based on environmental factors such as the amount of rain and space. Some grew their plots on small mounds; others gave each sister their own field and aligned them next to each other, then alternated fields by moving each species to the field to its right. The most common way I have seen it implemented is the mound method, though many people urge you to be selective about the plants you grow together and look towards using the indigenous varieties for your region as modern variety may overpower another plant or not grow in synch. Also, understand that this method of growing was historically used as a means to produce food for the winter, beans and corn were meant to dry on the stalk and the squash is meant to be stored in a cool dark place with good airflow away from ripening fruit such as a root cellar.
Photo by Seyfi Durmaz
1. Increased Garden Biodiversity
Photo by Yulia Rozanova
The first reason why I decided to create a three sisters plot is because I wanted to increase the variety of plants I grew in a given area and reduce the amount of times I plant a monoculture or a cluster of plants from the same family. I wanted to do this because higher ecological/biological diversity can help reduce the competition for nutrients between plants, increase pollinator/beneficial insect impact on the garden, and reduce the amount of pests/disease. It makes the system more resilient against abrupt change. This is discussed in Marcia Sheavly’s work, The Three Sisters: Exploring an Iroquois Garden when she writes, “lnterptanting has many advantages. Iroquois farmers adapted this ecological planting method to meet the needs of their crops and their people. Interplanted crops are not as attractive to pests, while large plantings of one crop tend to have more pest problems” (Sheavly, p.4). This is further evidence that proves more diversity means more food for the gardener. These benefits are generalities when discussing interplanting and not only associated with the three sisters method. When I learned about these factors all I could hear in my head was an opportunity to reduce the amount of time I spent micromanaging my plants and a reduced need to purchase organic pesticides. By utilizing the three sisters method I hope to bring more birds into my general area to protect my squash from squash beetles, I also hope to reduce the need to bring in outside fertilizer next year as the legumes are taking that job for me, and lastly I hope that the squash plants help prevent/slow the invasion of Bermuda grass into my growing space.
2. Increased Overall Yield For The Space
The second reason I decide to try out the three sisters method was the feedback I had heard regarding the overall productivity of the companion planting method. I have heard from word of mouth, forums, and gardening/permaculture books that this method produced greater yield than that of a single monoculture of a specific crop from one of the three based on the allocated space. I am a bit skeptical about what I have heard based on a paper I read from the University of Wisconsin-Steven’s Point by Rhea Martinez titled, AN EVALUATION OF THE PRODUCTIVITY OF THE NATIVE AMERICAN ‘THREE SISTERS’ AGRICULTURE SYSTEM IN NORTHERN WISCONSIN (Masters Thesis).
Martinez evaluated the yield and occurrence of pests in this paper, but this specific line stood out to me when Martinez states, “Statistical analysis of the yield data showed that yield/plant was not significantly greater for corn, squash or beans when grown together in the Three Sisters System versus conventional monoculture row cropping…When calories/acre were compared, however, the Three Sisters produced more calories/acre than monoculture corn, beans or squash at both sites A and B” (Martinez, p. 63). Her research indicates that though the method was not directly producing higher yields it did yield more available caloric energy through the variety that were produced. This is most likely why some native groups relied on this method for producing enough food to last them through winter. I think it is also wise to take the results with a grain of salt as the sample size was small and there were external variables such as lack of precipitation and poor bean germination (Martinez, p.64). It makes sense to me that our conventional way of growing food is efficient at growing one species of crop, but no one could realistically sustain themselves off of just one of these plants long-term without any nutritional deficits in my opinion. Plus who would want to eat just corn meal, or just beans/squash for an entire winter? Not me.
3. Space Efficiency
As mentioned above, if you are looking to get the most variety and caloric dense yield for the space one cannot beat the three sisters method. The only reason I can think of why someone would not plant this method based on the space is that they would rather use the space to grow more ornamental plants, perennial plants, or are planning on growing a conventional garden in large quantity with the idea that they are going to can or preserve a portion of it. Personally I love to have a bit of excess in the pantry and wouldn’t mind having some milled corn flour, dried/canned beans, or pumpkin puree. For me it was love at first sight. Some people have good success with growing non-native varieties, but emphasize that you want your stalks to grow strong and tall to allow your beans to grow tall. This worry can be avoided if you just build a bamboo tripod trellis over your corn. This may allow you to grow faster growing varieties of bean and not worry about them smothering your corn plants. So yes, there is some flexibility in the method if you wish to eat you harvest fresh rather than dry.
4. Role Model For Other Areas of The Garden
This method of garden design is very effective and beneficial when matching the right plants together based on their roles and interactions between each other. Every new gardener should be advised to start growing this way as it gives more room for error and requires less micromanagement to ensure that your plants don’t get chewed to oblivion. The reason it is so much easier is because it mimics how nature is when left untouched to a degree. If you go into a forest new or old and look at the plants growing, one will see that there are more than one species of plant. You will see that certain plants prefer to grow near other ones and others that are dying because of the plants they are around. This is what the Native Americans were picking up on. They figured out that plants, like people both have certain individuals we rely on and prefer to be around and people that we despise to even be next to. If you catch this little detail in nature and decide to research or experiment with what plants go with what, you should see a significant reduction in the work required from you and maybe an increase in production.
5. Overall Less Input Long Term
Lastly, three sisters requires less work long term. If you planted your legumes and did everything correctly you should have plenty of decaying organic matter for added compost/mulch and the nitrogen in the soil should be already fertilized which allows you to save both time, money, and muscle from having to buy, haul, and shovel manure or compost from an outside source. It could help reduce the need for fungicides, herbicides, and pesticides depending on the amount of diversity you have in your garden plot. To me it is a no brainer. Less work, more food… sounds like the way to go when trying to scrape food together for winter when everything is asleep or dead. And with the current increase of goods and services from the insane amount of inflation it is always nice to be able to rely on yourself and nature to save your wallet from feeling some of the effects.
Photo by Zen Chung
Conclusion
In the end, the decision to try out the three sisters method is up to you and your liking of corn, beans, squash and pumpkin/melon. It is one of; if not the oldest form(s) of agriculture in North America that we can find and was used to help many different tribes survive the harsh winters every year. In a time of global turmoil and economic stress we as humans need to look towards the past and their methods of survival to help get us through our hard times. Plus, this could be the start to adding more diversity in your garden and creating more produce from space that would be otherwise left barren. I hope to keep you all updated on how my journey goes and the seeds I will be using in my design.
Works Cited
Eames-Sheavly, Marcia. “The Three Sisters Exploring an Iroquois Garden.” https://ecommons.cornell.edu/bitstream/1813/3621/2/Three+Sisters+-+Exploring+an+Iroquois+Garden.pdf. Accessed 6 Feb. 2023.
Martinez, Rhea Trotman. AN EVALUATION OF THE PRODUCTIVITY OF THE NATIVE AMERICAN ‘THREE SISTERS’ AGRICULTURE SYSTEM IN NORTHERN WISCONSIN. UNIVERSITY OF WISCONSIN-STEVENS POINT , Aug. 2007.