As Seed Savers Exchange describes it: "A butterhead lettuce bursting with bright green leaves that tolerates both cold and heat. This variety was donated to Seed Savers Exchange by Nestor Keen, who received seeds from his Aunt Mae in 1937. Butterhead, 50-60 days."
Direct sow lettuce in the garden in April and again in late summer for a fall crop. Plant seeds every few weeks until mid-May for a continuous harvest. You can also start lettuce indoors in the winter and set out seedlings and seed at the same time!