When to start outside: RECOMMENDED
Early spring, 3 to 4 weeks before average last frost, and successive plantings thereafter every 3 weeks until 2 weeks before the first fall frost. (Skip very hot summers.) USDA zone 8 or warmer: sow in fall for winter harvest.
When to start inside:
6 weeks before average last frost and in summer when soil temperatures are too warm outside to germinate lettuce seed.
Special Sowing & Germination Instructions:
Barely cover seed with soil or plant no deeper than 1/8". Light and cool temperatures increase germination. When thinning lettuce, use the thinnings in salads. It can be planted in rows, but group plantings take up less space and are attractive. Double or triple rows also work. If direct seeding outside in late summer for a fall crop, remember that lettuce seed does not come up well in heat. Cover the seeded area with 2" x 6" boards to keep the soil cool for a few days until seed comes up. For early spring planting, cover soil with clear plastic to warm the soil to 70 degrees (the optimum temperature for lettuce). When seedlings appear, immediately take off the plastic.
