'Winter Density' lettuce looks like romaine lettuce but has the flavor of a butterhead variety. Although upright, this lettuce is not quite as tall as regular romaine. While 'Winter Density' is slower to bolt in the warm weather than other varieties, it withstands colder temps as well, making it a good option for a fall planting. Up to half of a plant's leaves may be harvested, leaving the rest to grow, or cut the whole head off at ground level. Consider succession planting (new plants every 2 - 4 weeks) in order to have lettuce throughout the growing season.