Agronomic and economic performance of organic forage, quinoa, and grain crop rotations in the Palouse region of the Pacific Northwest, USA

Volatile crop prices and a desire for sustainability have farmers considering alternative practices to increase revenue diversity and protect soil health. Organic management is rapidly expanding as an alternative to conventional agriculture, and quinoa (Chenopodium quinoa Willd.) is a potential new crop for organic systems in the Pacific Northwest. Here we tested the agronomic and economic effects of diversifying dryland crop rotations with organic quinoa in the Palouse region of the Pacific Northwest. Eight 3-year grain cropping sequences were compared based on metrics of crop productivity, crop quality, and economic performance. While the crop sequences affected these metrics, crop yields and quality were mediated primarily by weather across growing seasons. Cumulative yields were higher for crop sequences that started with chickpea compared to barley. Organic quinoa yields were lower than the yield potential for the region, but some 3-year sequences with quinoa produced similar net returns to some sequences with wheat. Mean returns over variable costs were $324ha−1 yr−1 for the 3-year sequence treatments; each treatment averaged positive net returns to variable costs despite some individual years having negative returns. The highest net returns to variable costs were in sequences that grew wheat and those that started with chickpea. Returns over total costs for the 3-year sequence treatments averaged -$33ha−1 yr−1. The organic cropping systems (the total 8-year crop rotations including 5 years of organic alfalfa) produced higher returns over variable and total costs ($615ha−1 yr−1 and $168ha−1 yr−1, respectively) than a typical conventional rotation with county average yields during the same 8-year period ($477ha−1 yr−1 and $82ha−1 yr−1). Our results show that premiums for organic alfalfa and grains make these organic cropping systems economically viable for dryland production in the Pacific Northwest. Advances in organic weed control and regionally adapted quinoa varieties would further reduce the risk for farmers attempting this cropping system diversification.