Lettuce is so easy to grow it can be started indoors for early transplants or sown directly in the garden. In fact, doing both is recommended to get maximum production.
Start some lettuce seeds indoors in peat pots a few weeks before the last frost date in your area. Provide the seedlings with plenty of sunlight or keep them under artificial lighting until ready to move into the garden. Transplant the seedlings as soon as the soil can be worked in the spring. If a hard freeze threatens, protect the seedlings with a cloche or row cover. Reserve a number of lettuce seedlings to fill empty spaces in the garden as the season progresses.

To sow lettuce directly in the garden, simply plant the seeds about 1/4 inch deep, tamp them down, and water.

Lettuce is ideal for succession planting. Sow seeds every two weeks for production throughout the season, starting with early lettuce varieties, using heat-tolerant varieties as your main crop, and then switching to fall crops late in the summer.