Microgreens are defined as a wide range of vegetable and herb seedlings that are harvested shortly after the emergence of the first true leaf and prior to leaf expansion/senescence of cotyledons. Microgreens represent a quick turn, potentially high value crop for greenhouses and indoor production. Because there are a wide diversity of species used, recommendations for cultural practices are lacking for many. Relatively little information is available on microgreens responses to light and carbon dioxide.
Because many microgreens start with a relatively large seed that can provide initial nutrition to the developing seedling, it is thought they are relatively less responsive to light and CO2 than their full-size counterparts (ex., baby greens or head lettuce). However, experimental data is needed to evaluate these claims. The objective of this study was to determine how three species of microgreens would respond to daily light integral (DLI) varying from 3 to 12 mol·m-2·d-1 and carbon dioxide enrichment from 400 ppm (ambient) to 1,000 ppm.
Three microgreen species; arugula (Eruca sativa L.), mizuna (Brassica rapa L. var. japonica) and mustard (Brassica juncea 'Garnet Giant') were chosen for this study. The seeds were purchased from Johnny's Seed and were selected to represent a diversity in sensory attributes for both vision and taste. We also choose these three as their share similarities in seed size and number of days from seeding to harvest.
Read more at e-gro.org