50 to 55 Days to maturity. Lactuca sativa. New Red Fire Leaf Lettuce Seeds. Annual, Heirloom, Open Pollinated. This large ruffled and loose-leaf lettuce is green at the base of the plant and is a lovely dark red at the edges of the leaf. The Red Fire loose-leafed head is quite large and resistant to common diseases. It is very resistant to bolting and can therefore be harvested over a longer period than most lettuce varieties. Approximately 25,000 seeds / oz.