There has been a lot of advances in horticulture and agriculture in the last 150 years. Many of us can probably remember being introduced to George Washington Carver in history classes.
Famous for his research of peanuts and sweet potatoes, he also understood and promoted the principles of soil building, crop rotation, and companion planting.
One of the most impactful practices he was able to promote in much of the South was rotation between peanut and cotton plantings. This practice greatly improved farm economics and diversified the crops being brought to market. As important as this was, our ancestors also knew a lot about raising crops, and did it without the conveniences we have today.
This brings us to a term called “The Three Sisters.” This memorable little phrase actually describes three key crops that grow well together. They are corn, climbing beans and squash. I first heard about the “Sisters” to describe the trio of plantings commonly found among American Indians in the northeastern U.S. It’s highly likely that the practice of putting a fish in the ground (which adds nitrogen and much needed nutrients to the soil) when planting corn or maize was in the context of planting the three sisters. This combination is a form of sustainable farming as well as companion planting.
Companion planting is the practice of grouping certain plants together that will give a better result than would be experienced if each crop were planted separately. In the case of corn, climbing beans and squash, not only do they assist each other, but the combined nutritional contents when they are eaten is impressive. Corn is a good source of carbohydrates, and beans provide proteins and amino acids. Squash provides important vitamins, and the seeds have vegetable fats that the other two crops lack. It’s been said that this trio of foods are called “the sustainers,” because together they provide a fairly balanced diet.
This was especially important in earlier cultures. The practice of the Three Sisters wasn’t limited to the time or place when the Pilgrims’ hosts taught them about agriculture and hunting in their new setting. This approach has been found in many places throughout the world, both before and after the American Indians. It’s a tried and true practice, and it will work well in your garden.
The reason is each of the three types of plants possess characteristics that also benefit the others. So each plant does double duty. Corn rapidly reaches for the sky, and puts some shading over the ground. Because corn is a type of grass, it uses nitrogen rapidly as it grows. Without amendments or companions, it will rapidly deplete the soil of its nitrogen.
Beans are legumes. As such, they have the ability to access atmospheric nitrogen and convert it to ammonium (a nitrogen-hydrogen compound) that other plants can access. This is called “nitrogen fixation.” Most legumes have nodules in their root system to produce nitrogen compounds that allow the plant to grow. Some of this nitrogen is available to other plants as well when the plants are alive, but, even more so, yield nitrogen compounds into the soil when the plant dies.
While the beans help the corn with its appetite for nitrogen, the corn helps the beans by providing something to climb on — to reach into the sunlight and give more stem length that is off the ground. Squash rounds out the trio by providing ground shading, greatly reducing weed pressure, lowering soil temperature, and by making the environment uncomfortable for many insects with its prickly stem and leaf structures.
In addition to the benefits already mentioned, “Three Sisters” planting is sustainable — meaning you can plant the same thing, if you so desire, in the same place year after year with few amendments. Having said that, it is still important to remove all plant materials at the end of the season to eliminate or greatly reduce the amount of overwintering pests.
If disease does form in subsequent years, then crop rotation will be a great help. Use cover crops such as rye, buckwheat, clover, oats, and field peas that can all be grown and then mowed down or tilled in to incorporate them completely before seed formation. The decaying plant tissues bolster nutrients and help control diseases. The tilling helps destroy overwintering insect eggs as well.
For each plot or raised bed, you will need about 100 square feet, or a 10 foot by 10 foot area. You will be planting nine clusters of plants. You will be planting corn most plentifully, a lesser amount of beans, and one or two squash. It is possible to do this method in longer and narrower beds or plots, but be aware that corn pollinates much better in square blocks where there are stalks adjacent in all directions. Because corn pollination happens via a combo of gravity and wind, single rows or plots of two or less rows will struggle with good pollination. Square plots or denser stands of crops will also fare much better in windy conditions that we experience ongoing here.
The planting layout is straightforward in a 10 by 10 plot and is comprised of nine hills, each about the size of a large dinner plate and hilled up about 6 inches higher than the plot’s soil level. Imagine if there was a “number nine” dice — each dot on the dice represents a plant hill. Leave a two-foot perimeter empty around the edges of the square plot. The top, left hand corner of your two-foot perimeter will be the center of your first hill. Then measure over three feet and that is the center of your second hill. Three more feet, and that is the center of the third hill. This will leave a two-foot, right hand perimeter.
Plant the second and third rows the same way, measuring down three feet from the center of each first-row hill. The result is a grid of nine plant hills, laid out in a symmetrical fashion, with a two-foot perimeter all around the grouping of plants. The interior of the grid has growing space because each planting hill is centered three feet away from adjacent hills.
As you will create clusters of plants in and immediately around each hill, plant seven corn seeds in each hill, one in the center and six in a ring spaced equally around the mound edge. Plant 1 inch to 1-1/2 inches deep. Wait until the soil is warm, and be sure to plant only the same variety of corn — don’t mix them.
When the corn sprouts, start gently weeding and hilling soil up against the tender corn seedlings. When they are about 6 inches tall, plant four pole bean seeds (blue lake types are recommended) around the perimeter of each hill. At the same time, choose two diagonal corners of the plot and plant a single squash in each location. Winter squashes are a good choice, including pumpkin.
You can grow summer squashes as well but keep in mind that some varieties grow fast and large and could overwhelm your plot (Remember that “mongo” zucchini plant you had? Get the idea?). Train the growth of each plant towards the center of the plot to gain shading and weed control benefits, as well as keeping aisles clear outside your Three Sisters garden. Of course, if you want to plant more than one plot, have at it.
In the first year, nitrogen from the beans will not be readily available to the corn, so you’ll need to fertilize the corn two or three times during its growing period to get the crop you desire. In the second year and beyond, nitrogen will become available to your corn from the previous season’s bean planting. Be sure to keep the plot adequately watered, and avoid overhead irrigation. Either hand water at the base of the plants or use drip irrigation. This will reduce water use and minimize plant diseases. Monitor the plants ongoing for pest damage and act accordingly.
One last thing: Since most of us are used to open areas and symmetry in our gardens, the appearance of a Three Sisters garden may be disconcerting. With all the intertwining of the plants and differing growth habits, the plot is crowded and less manicured looking. You’ll need to make the determination if all the benefits we’ve talked about outweigh less ready access and less uniformity.
Enjoy having some new relatives around your garden this year!
Upcoming gardening events
Thanksgiving Point Tulip Festival now through May 3 in Lehi. See 250,000 tulips on display. Fridays and Saturdays feature music and food vendors as well. Admission is $15 for adults and $12 for children. Closed Sundays. For more information, visit www.thanksgivingpoint.org.
Gardening Walk and Talk, Saturday, May 10, 10 a.m. to noon at the Fawson Residence, 187 Waterhole Way, Grantsville. See this beautiful oasis of ponds, bridges, trails, pastures and more. Join Gary Fawson and Jay Cooper as they stroll the grounds and chat about plants and growing methods. There is no charge. For more information, call Cooper at 435-830-1447.
The next Monthly Gardener’s Breakfast Get-Together will be on May 17 from 9 a.m. to 11 a.m. at the Stockton Miners Café, 47 N. Connor in Stockton. Gardening topics, challenges, successes and collective advice will be shared. Admission is the price of ordering an item from the menu. For more information, contact firstname.lastname@example.org or call 435-830-1447.
All about Tomatoes! Attend this free workshop by Tooele County Master Gardeners on Wednesday, May 28 from 7 p.m. to 8 p.m. at USU Tooele Extension, 151 N. Main, Tooele. Walt Barlow will give insights on varieties, types, starting, planting, care, harvesting, pest and disease control. For more information, contact email@example.com or call 435-830-1447.