Ruby Red Lettuce is the deepest red variety of lettuce there is and the more sunshine it has, the redder it gets! This is a medium size and compact variety of lettuce that is also heat tolerant and slow to bolt. Ruby Red Lettuce is an annual crop, meaning that it will produce heads of lettuce which can be harvested in a single season. . If allowed to go to seed, you can regrow this crop the following year. Ruby Red Lettuce is an excellent choice for use as a garnish, or to add an extra splash of color to salads. Plant lettuce during cool weather, as soon as the ground can be worked in the spring. Lettuce does well in early spring and fall weather and the seedlings can tolerate a light frost.