Is your crop mix in need of a little boost? The answer may lie in a better understanding of consumer food trends. For example, consider the rise of quinoa in the American diet. The crop grew rapidly in U.S. consumer popularity from 2000 to 2015, and it continues to hold steady market value. And it appears more people even know how to pronounce it (KEEN-wah).

Quinoa continues to gain acres in the U.S. It is a cold- and frost-tolerant grain crop that originated in the high-altitude Andes Mountains in South America. University of Idaho researchers report that quinoa is best planted early, so that it flowers before summer temperatures peak above 90 degrees F.

Optimal water input, either precipitation or irrigation, is 10 to 15 inches per year. UI found quinoa yielded 3,300 pounds per acre with about 18 inches of water, compared to 940 pounds per acre with 7 inches of seasonal rainfall and irrigation.

Quinoa grows well in soils ranging from coarse sand to heavy clay. It is a salt-tolerant crop, though salinity tolerance percentages differ among varieties. Nitrogen rates needed for quinoa to yield acceptably range from 90 to 135 pounds per acre.

Controlling weeds

Weed control can be challenging in quinoa fields. Quinoa plants emerge quickly, but the crop’s early growth is slow. It is closely related to the common lambsquarters and pigweed, and this severely limits herbicide control.

The University of Idaho recommends a couple of weed management approaches. One way is to let weeds emerge, and then control them with tillage and/or non-residual herbicides before planting. This helps deplete the weed-seed bank to create a clean bed for planting. Another method is to plant quinoa early enough to enable crop canopy development before some weed species emerge.

From 2010 to 2017, Washington State University researchers studied how quinoa, grown as certified organic, performs in rotation with other crops. First, the fields held alfalfa for five years to build soil, control weeds and reap the high economic returns of organic alfalfa hay. The following three years saw a rotation of barley, chickpea, and quinoa or spring wheat.

Rachel Wieme, a WSU Crop and Soil Science graduate student and project lead, notes that the order of crops in the rotation affected yields and soil quality. “Higher average yields were observed for barley grown following chickpea, compared to following alfalfa,” Wieme says. “There was a consistent trend of average quinoa yields being slightly higher when following barley than when following chickpea.”

Wheat and quinoa plants in Washington State University test plot
IN THE MIX: Strips of crops in the WSU rotation study show wheat and quinoa, and they demonstrate the potential for the new small grain to be part of your rotation.

Higher nitrogen levels remained in the soil after the quinoa rotation, when compared directly to spring wheat. “The quinoa plant residues carry higher levels of potentially mineralizable nitrogen than cereal residues, such as barley and wheat,” Wieme explains. “This can help increase soil nutrients, especially in organic crop systems.”

Through the organic quinoa crop rotation study, WSU evaluated the high-value crop for the climate of eastern Washington state. “We learned the quinoa varieties we used weren’t a good fit for the Palouse region’s [of southeast Washington] climate,” Wieme says. “We were limited to growing North American varieties of quinoa, and hot temperatures during certain stages of their growth are detrimental. During the study, we had very low seed yields for quinoa.”

Choices available

There is extensive genetic diversity between quinoa varieties. Certain varieties thrive in western Washington state’s maritime climate, including the Willamette Valley. Others grow well in the arid, high altitude of southwestern Colorado and southeastern Idaho.

“There isn’t one perfect climate for quinoa,” Wieme says. “It’s just finding the varieties that do well in your particular climate.”

Quinoa is harvested similarly to canola and other small grains, though it requires further processing to remove the bitter seed coating, saponin, before human consumption. There are two at-scale U.S. processing facilities: Ardent Mills’ Andean Naturals Quinoa in Yuba City, Calif., and American Mills in Idaho Falls, Idaho. Some farms process their own quinoa.

Producers who consider growing quinoa should either get contracts from the larger processors and financially account for the increased cost of trucking to the facility, or plan how to process quinoa on their own farms.

With processing secured and optimal varieties identified, Wieme recommends quinoa as an early-season crop, for its beneficial role rotated with other crops and its market value.

Hemken writes from Lander, Wyo.

Source: Melissa Hemken, Western Farmer-Stockman