You can get a head start and prepare your planting site in the fall. Break up the soil and rake a nice seedbed before covering it with mulch. Lettuce seeds are planted in early spring as soon as the soil can be worked. Don’t worry about a little frost; it won’t hurt your lettuce. Just rake back the mulch and plant.
Lettuce seeds are really tiny. You can just broadcast them over a planting bed and cover with a dusting of growing medium. Or, you can sprinkle them into lightly dug rows and then cover with ¼ inch of soil.
Water the soil both before and after planting your seeds to give it a good soak. Once planted, the seeds should sprout within 10 days. From this point on, plant new seeds every two weeks through the fall for continuous fresh butter lettuce. During the summer months, cover them with shade cloth during the hottest parts of the day and choose heat-tolerant varieties like:
- Red Cross
- All Year Round
- Summer Bibb
The most important part of growing lettuce is keeping it moist. On hot days you may have to water twice to keep lettuce from bolting. Use frost covers in the earliest days of spring to prevent leaf damage, and then switch to shade covers in the high summer.
If you are using mulch, slugs and snails can be an issue. You can hand pick them just after sunset when they come out to munch. It significantly sets them back. Or, build snake habitat throughout the garden by stacking up pieces of urbanite or stone. Another option is to run ducks through the mulch before planting. They not only eat slugs and snails but the offspring and eggs also. Garden supply stores sell organic slug baits for those desperate times.
About 6-8 weeks after planting, butter lettuce will be mature enough to pick leaves from. Pick the outer or lowermost leaves while leaving the central crown intact. The plant will continue to grow and give leaves all season.
Another option is to wait until the lettuce has formed a loose head, and then harvest it all at once. 55-75 days from planting depending on your variety, butter lettuces will have formed a fully mature head. Don’t wait any longer or the leaves will be tough and may start to taste bitter. Simply cut the stem right at ground level. Store the head in a plastic bag with a paper towel to soak up excess moisture. It will keep in the fridge for up to 3 weeks.