Among many Native American tribes, growing the "three sisters" — corn, beans, and squash — was a tradition, and it was felt that these three thrived if planted together.
Corn provides a natural pole for the beans to climb. Beans, which are legumes, fix nitrogen on their roots, thus enriching the soil for the corn, and provide some stability for the corn.
Squash, which is shallow-rooted, acts as a living mulch, shading the soil to keep weeds down and preventing soil moisture from evaporating. Many kinds of squash have spiny vines, which discourages small predators from approaching the beans and corn.
But there are still more benefits. All three of these plants leave a large amount of residue at the end of the season, which can be incorporated back into the soil to build up organic matter and improve the soil for next year's crop.
Corn, beans and squash also complement each other nutritionally. Corn provides carbohydrates; dried beans are rich in protein, balancing the amino acids found in corn. Squash is nutrient-rich, too, and provides oil in its seeds.
If you would like to try growing the three sisters in your garden, it involves attention to timing, seed spacing and varieties. If you simply plant all three at the same time and in the same hole, the result will be a snarl of vines that will overwhelm the corn.
I'd suggest reserving a 10-by-10-foot area in full sun for your Sisters Garden. Amend the soil as needed, with compost or aged manure. Corn is a heavy user of nitrogen, and the nitrogen from the beans will not be available for it until next year. Use a soil thermometer to be sure the soil is 60 degrees or warmer before planting corn.
With string, mark off three 10-foot rows, five feet apart. In each row, you'll make corn/bean mounds. Native Americans made mounds about 4 inches high and 18 inches across, with flattened tops. The center of each mound should be 5 feet from the center of the next. In the first row, make two mounds; in the middle row make three, and then two more in the third row, for a total of seven corn/bean mounds. Making a little crater on the top of the mound will help hold water.
Plant four corn seeds in each mound, in a 6-inch square. Keep the soil of the mounds moist, but not wet.
When the corn is 4 inches tall, it is time to plant the beans and squash. Soil temperature should be 70 degrees for them. Plant four climbing (not bush) bean seeds in the corn mound, about 3 inches away from the corn plants. Native Americans used beans dried; care must be taken not to step on the squash vines if you pick them green.
Make mounds for the squash like you did for the corn and beans, in between the corn/bean mounds. You'll have three in the first row, two in the middle row, and three in the third row, for a total of eight. Plant three squash seeds, 4 inches apart, in each mound. When the squash seeds emerge, you may want to thin them to two per mound.
This would be a great project to do with kids, but with or without them, it may make you realize how learning this technique from Native Americans helped our early settlers to survive.
Carol Oneal is a past president of the OSU Jackson County Master Gardeners Association. Email her at firstname.lastname@example.org.