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The three sisters companion planting combines corn, beans, and squash vines. These three plants make up the perfect companion planting trio. The three sisters garden layout is great for maximizing crop yield per foot, even if you’ve only got a small space. Plus, corn, beans and squash all benefit each other. One provides support, one provides nitrogen, and one provides protection.
The three sisters garden layout is an ancient Native American tradition, and despite its mythical background, science shows that planting corn beans and squash together works exceptionally well.
For those with small growing spaces, you can maximize the variety and quantity of food using the three sisters method.
Even if you’ve got loads of growing space, there are still some very good reasons to use the three sisters garden as your companion planting staple.
About the Three Sisters Method
According to legend, these three plants were gifts from the deities, to sustain the people spiritually and physically, to be grown, eaten, and celebrated as a trio.
Thought to be called the Three Sisters because each plant brings something beneficial to the others, these plants are the perfect example of organic symbiotic agriculture.
Aside from the obvious benefits of getting a huge amount of produce from a small space, and without depleting the nutrients in the soil, there are several other reasons to grow the Three Sisters, and those reasons give this technique its name.
The Big Sister
The corn is the “big sister” of the trio. It’s the oldest, as you plant the corn seeds first. The sweet corn is the tallest plant in the three sisters garden. And its strong stem provides much-needed support for the pole beans (or runner beans).
The Middle Sister
The bean vines, called pole beans or runner beans, are the middle sister of the three sisters. They pull nitrogen from the air into the soil. This is known as nitrogen fixing and is vital for soil and plant health. The sister bean puts nitrogen into the soil in a bio-available form for the use of the other two siblings. And, because they’re climbers, the beans wrap around all three plants, holding them together as a close-knit group.
The Little Sister
The squash vines, the youngest of the three sisters, flourish in the nitrogen-rich soil. The squash plants use their large, fast-growing leaves to protect the other sisters.
The squash leaves cast shade over the bare earth, keeping it damp and moist, preventing excessive evaporation and runoff. This keeps all the sisters nourished and hydrated. Because the leaves and stems are prickly, it also fends off some insect and mammal pests.
Growing the Three Sisters for Healthy Plants and Big Harvests
Growing these three crops produces large, healthy plants, which immediately puts them at less risk of disease and insect infestation.
You can further help deter any potential pests by adding marigolds, nasturtiums, and catnip around the exterior of the mound, as they all repel squash bugs.
Marigolds also keep slugs away from your crops, and the bright flowers encourage bees to promote pollination. Nasturtiums also encourage pollination, and their flowers are edible, making a delicious addition to salads.
We’re big proponents of companion planting, as it’s invaluable in the organic garden for both plant and soil health. Check out our favorite companion planting combinations for vegetables.
Nutrition
The three sisters aren’t just good for getting a big harvest from a small space, the crops they produce are complimentary and provide fairly well–rounded nutrition. The corn plants provide carbohydrates, the beans are high in protein and fiber, and the squashes are exceedingly rich in vitamins and minerals.
Plus, they all store well and can be used year-round, making each crop incredibly valuable.
How to Plant a Three Sisters Garden
Before you get excited and start planting, remember that all three of these crops are warm-season plants. So you’ll need to plan your planting accordingly, as they’ll die off at the first frost and they’ll struggle to thrive if you plant too early. For each plant, check your local planting calendar for accurate planting dates.
While there are many traditions and variations for planting a three sisters garden, here’s a basic, classic setup that should work for most growing spaces.
- When prepping the soil, make a mound of earth around 4 feet wide and 1-foot high for every six corn plants you plan to grow.
- Once the danger of frost has passed, it’s time to start with sister corn. Plant six corn kernels on top of each mound. Space them around 10 inches apart in a circle roughly 2 feet in diameter.
- Once the corn is a couple of inches tall, around three weeks after you planted the corn, it’s time to plant sister bean. Around every corn seedling, plant four bean seeds, spaced evenly.
- Approximately two weeks later, or around one week after the beans start to emerge, it’s time for sister squash. Plant six to eight squash seeds, spaced evenly around the base of the mound.
I’ve had success with both direct sowing and with using transplants. It really depends on the growing conditions in your area, how long your growing season is, and how easily you can keep mice and other pests off your seeds if you choose to direct plant.
Here in the UK, I usually use transplants, because the growing season is shorter and temperatures overall cooler than many other parts of the world. So, starting my three sisters from seed indoors lets me get ahead of the weather and get a bigger, longer harvest.
Whether you direct sow, start all the seeds indoors, or buy transplants, it entirely up to you.
Choosing Three Sisters Seed Varieties
Ok, given that this technique has been practiced for hundreds of years, it follows that many of the modern varieties aren’t best suited to this method – they’ve been “improved” over the years to bring out certain characteristics and to reduce others.
Therefore, when deciding which seeds to use for three sisters gardens, go with heirloom varieties whenever possible.
Pay close attention to your plating zone, and choose seeds that will thrive in your climate. You may have to experiment with a few varieties to find the best possible combination.
Choose pole beans like Scarlet Runner, Hopi Light Yellow, Trail of Tears, or Cosse Violette. Avoid bush beans, which can be smothered by the squashes, and avoid the most vigorous hybrid climbers, as these may pull down your corn stalks.
When choosing corn varieties, you want robust heirloom types, not weedy, thin-stalked hybrids. Go with a hardy, robust dent corn or sweetcorn variety like Black Aztec or Hopi White.
For squashes, opt for a small-leafed vining variety. Most pumpkin plants are simply too big, with huge leaves that create too much shade and inhibit airflow. Summer squash varieties, like yellow crook-necked squashes are a good choice, as are Hubbard winter squash types. You can also go with acorn or pattypan squashes, or smaller butternut types as these trail but tend to have smaller leaves.
Three Sisters Variations
There are many different variations of three sisters gardens. And you can do what works best for your growing space. You can plant in rows, plant in squares, go with the hill method, or make use of a smallish raised bed. Take a look at some of the traditional configurations of the three sisters planting methods from different Native American tribes.
Three sisters garden planting variations with corn seeds, bean seeds, and squash seeds
Three sisters garden variations including three sisters garden field and waffle layouts
The Other Sisters
These ancient companions also had other sisters in some cultures. Amaranth and sunflowers being the most common fourth sister and fifth sister. These plants both provided shade during the heat and bright light of the afternoon. Plus, amaranth seeds and greens along with sunflower seeds are valuable food stuffs. And, of course, the bright flowers of both help to attract pollinators.
A group of us in a friends garden tried a variation of this. It worked but not to its full potential. Thank you for this explanation. It was simple and easily drawn out. I am excited to try this again this year. Thank you and happy planting for 2021
Hey Kenda,
Good luck to you too! If your plants need a boost, you can always make some nettle tea. But hopefully your plants will thrive this year! 🙂
This is a good explanation of the three sisters which I am going to try here in Australia when spring arrives.
Good luck! It’s definitely worth it, particularly if you’re growing in a smaller space. Just remember to add plenty of compost, manure, or other nutrient-rich organic matter to the growing area before you plant, as planting all three varieties in a small space puts significant nutrient demand on the soil.