Growing the Three Sisters

 By Irene Shonle, El Paso County Extension

Three sisters illustration (from gardening.cals.cornell.edu)

This coming summer I have decided to try growing the traditional grouping of crops called the Three Sisters – corn, beans, and squash.   This is one of the oldest companion planting groupings, first planted by Native Americans in many different regions.  It is rich in tradition and indigenous knowledge, and can produce a lot of food. The idea is that the corn provides the trellis for the beans, the beans provide nitrogen for the hungry corn, and the squash shades the ground and reduces both water needs and weed seeds. 

I have been growing beans and squash for a while now, but had avoided corn due to the high numbers of raccoons in my area.  Supposedly, the combination of the prickly squash leaves and the raspy, tangly bean vines reduces raccoon visitation.  We shall see -- I have the perfect conditions to test this concept.

For the three sisters,  it is traditional to use a flour or popping corn with taller stalks, a pole bean, and a squash. Many sweet corn varieties don’t have sturdy enough stalks, and bush beans do not climb up the corn stalks. I decided to go with a dry bean rather than a green bean, because I don’t want to be wading into the plot on a daily basis to pick green beans.   Sometimes a fourth sister is planted, which is traditionally a sunflower or a bee plant.  I have both growing in my yard, and they will probably be on the edge of the three sisters area as well as elsewhere in the garden. These help to draw in pollinators.

It’s been fun figuring out what specific varieties I will grow. I do not have an easy way to grind flour, but I am a popcorn fan, so that’s what I decided to go with. Glass gem has irresistibly beautiful multi-hued kernels, and grows at least 6 feet tall. It’s also supposed to make yummy popcorn, and can double as a decoration.   For the beans, I want a variety that is harder to find in stores, so I am currently leaning towards the Hopi red bean, which is supposed to make wonderful chile.  I considered Gigante beans, which I would really like to try, but I have a feeling that they may be a little too exuberant.  Maybe I’ll try growing a few up some of my giant sunflowers (they were 15’ tall last summer), if I can find the seeds (they are hard to come by in this country- I may have to resort to ordering a pound of beans intended for eating).  Finally, for the squash variety,  I will likely plant a couple of summer squash varieties and perhaps either a Lakota squash (which is a cultivar derived from a landrace grown by Native Americans in Nebraska and crossed with a Hubbard: https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1637&context=agronomyfacpub  and somewhat deceptively named: https://medium.com/@MisterOctober/the-lakota-squash-is-a-regrettable-deception-ecd549cb73a5) or a pink banana squash.

 

How to grow:

Test your soil first. Corn is a heavy nitrogen feeder (even with nearby beans), and squash will be more productive with fertile soil.  Adding compost before planting can be helpful to provide a little extra water-holding capacity and to improve soil structure and a add a few nutrients.

Zuni waffle garden. Photo Credit: A:shiwi A:wan Museum Photo Archives

There are many, many different suggestions for the layout for planting, with different layouts traditional to different areas of the country.  Because I live in a hot, dry area, I intend to use the traditional Zuni waffle garden design to conserve water.  The waffles are created with raised soil edges, and they are almost the opposite of raised beds.

Probably one of the biggest considerations for the planting design is to plant the corn in blocks so they can become adequately pollinated.  Also, grow only one variety of corn to avoid cross-pollination.

Three sisters planting diagram (c=corn, b=bean, s=squash)

I am going to plant in a 15x15’ area, with 9 ‘waffle’ squares.  In the center of every other waffle, I will plant the corn in a circle about 18’ diameter, and will plant 5 seeds of corn, with one in the middle, and the rest evenly spaced. There will be five blocks of corn, which should provide reasonable pollination. The squash will go in alternating waffle squares (so, four squares).

Once the corn is 4” high, I will plant the beans (one per corn plant).   It is a good idea to soak the corn and bean seeds before planting for at least 8 hours.