Red Stemmed Microgreens Seeds. Raphanus sativus. Non-GMO. Microgreen Harvest 8 to 12 Days. Selected specifically for their red stem / green leaf (cotyledon) combination, these red stemmed radish seeds grow stunning microgreens with the two contrasting colors. A great choice as a garnish or anytime you want the spicy bite of radish with the red/green color combo. About 3500 Seeds / Ounce.