Characterization of Microgreen Growing Operations and Associated Food Safety Practices

Microgreen growing operations are an emerging industry. This study represents the first national survey of microgreen growers in the United States. An online survey, answered by 176 growers, included questions about farm demographics, growing techniques, microgreen varieties grown, and food safety practices. Microgreen growing operations that earned <10,000 USD/year in microgreen revenue (62%) producing microgreens in trays on stacked, artificially lit shelves (40.3%) dominated the response pool. Most farms surveyed opened after 2010 (75%). These farms primarily grow microgreens using peat (17.6%), coco coir (14.2%), or soil (15.3%). Sunflower (28%), peas (27%), and radish (29%) were the most popular microgreen varieties produced. Chi-square tests of association were performed to identify relationships between farm characteristics and food safety practices. Statistically significant relationships were found between growing media testing at least once per year and total number of employees (P = 0.015) and total number of employees who directly handle microgreens (P = 0.001), possibly indicating that larger operations are better equipped to engage in routine quality assurance procedures. Production system type (P = 0.001) and total number of employees (P = 0.011) were associated with pregermination seed disinfection; however, in this instance, smaller operations (i.e., average of four employees) reported seed disinfection more frequently than larger operations. Routine documentation practices were also significantly associated with annual microgreen revenue (P = 0.003), passing a good agricultural practices (GAP) audit (P = 0.001), and number of previous food safety trainings attended (P = 0.001). Overall, this study aims to inform research, outreach, and training efforts on the growing systems, microgreen varieties, and production practices relevant to microgreen safety.