74% Germination - Non-refundable clearance seeds. 40-70 Days to maturity. Lactuca sativa. Organic Spring Mix Lettuce Seeds. The Spring Lettuce Mix is a blend of lettuces chosen especially for Spring planting. They offer a good range of leaf colors and forms. A good way to start off the Spring season. Cook's Garden Favorite. Approx 37,307 seeds/oz. Click here to view regularly priced, high germination seed.