5 days for microgreens. 45 days to maturity.Brassica juncea. Cho Kara Mustard Seeds. Non-GMO, cool-season, year-round annual, heirloom. This mustard variety is bred especially for microgreen production and has a hot flavor. The cotyledons or seed leaves are forest green with ivory stems. It will be overwhelming for many, except for hot mustard lovers. For large sprouts or microgreens, sow seeds in spring to summer in sandy soil in a bright but cool location. ~ 14,000 seeds / oz.