Newswise — June 1, 2017 – Corn, beans, and squash—the “three sisters”—have traditionally been grown together for best results.  The Soil Science Society of America (SSSA) June 1 Soils Matter blog post explains how companion plantings use plants’ strengths to their best advantage.

“Cooperative synergy is behind the approach of companion planting,” says Farrah Fatemi. Fatemi is assistant professor of environmental studies at St. Michael’s College in Vermont. “In companion planting, ecologically complementary crops are grown alongside one another. Native tribes in North America, most notably the Iroquois, utilized the three sisters approach.”

  • Corn, with its tall, strong stalk, is the leader.
  • Beans, which climb the corn stalks, bring the gift of nitrogen fixation, They work with soil bacteria to provide vital nitrogen.
  • Squash has broad and prickly leaves to protect the soil, prevent weeds, and reduce pests.

Other companion plantings, such as radish-spinach-bush beans, take advantage of fungi in the soil.

“Companion planting is a great way to promote crop productivity by harnessing natural synergies in the soil/plant system. Ultimately, this strategy can make for healthier ecosystems by reducing the need for synthetic fertilizers and pesticides,” Fatemi explains.

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The Soil Science Society of America (SSSA) is a progressive international scientific society that fosters the transfer of knowledge and practices to sustain global soils. Based in Madison, WI, and founded in 1936, SSSA is the professional home for 6,000+ members and 1,000+ certified professionals dedicated to advancing the field of soil science. The Society provides information about soils in relation to crop production, environmental quality, ecosystem sustainability, bioremediation, waste management, recycling, and wise land use.