How to Grow Lettuce From Seed

Lettuce thrives in cool weather and can handle light frost, so plant early and often. Direct-sow or transplant your first crop as soon as the soil can be worked in spring, about two to four weeks before your last frost, and sow small batches every two weeks for a steady supply. As summer heat arrives most lettuce bolts and turns bitter, so pause in midsummer and start again in late summer for a fall harvest. In mild-winter regions like the Deep South, California, and the Gulf Coast, lettuce grows right through fall, winter, and spring.

Sow lettuce seed shallowly, no more than an eighth of an inch deep, because it needs light to germinate; simply press the seed onto moist soil and barely cover it. Keep the surface consistently damp and seedlings will appear in seven to fourteen days. You can direct-sow right where plants will grow or start seeds indoors and transplant seedlings out when they have a few true leaves. Thin or space plants four to twelve inches apart depending on type, giving leaf lettuces less room and full heads more, and water gently so the tiny seeds and shallow roots never dry out.

Lettuce is easy to please if you keep it cool and moist. Give it full sun in spring and fall but part shade in summer, and water lightly and often, since its shallow roots dry out fast and stress brings on bitterness and bolting. Feed with a balanced or nitrogen-rich fertilizer to push tender leafy growth, and mulch to hold moisture and keep the soil cool. Pick outer leaves regularly, keep weeds down, and watch for slugs, which love tender lettuce as much as you do.

Lettuce plays well with almost everything and is a favorite for tucking between slower crops. Good neighbors shade its roots, repel pests, or use space it does not need. Carrots, radishes, beets, and onions are all classic partners. These three are especially easy to add in one click:

Harvest lettuce young and often for the best flavor. For leaf and butterhead types use the cut-and-come-again method, snipping outer leaves an inch above the crown so the plant keeps producing for weeks. Cut heading types like romaine and iceberg at the base once the head feels firm and full. Pick in the cool of the morning when leaves are crisp and hydrated, and harvest the whole plant before it starts to bolt, since a lettuce sending up a flower stalk quickly turns bitter.

Lettuce is the backbone of the salad bowl, but it does far more than that. Crisp romaine and iceberg add crunch to sandwiches, wraps, and Caesar salads, tender butterhead makes delicate lettuce cups and wraps, and colorful loose-leaf types brighten any mixed salad. Lettuce can even be grilled or braised, and homegrown leaves are far sweeter and fresher than anything from a store. Low in calories and rich in vitamins A and K, it is a crop you will pick almost every day.

• Bolting: hot, long days make lettuce send up a flower stalk and turn bitter. Grow in cool seasons, water evenly, and give afternoon shade in summer.
• Poor germination: lettuce seed needs light and cool soil. Sow shallow, keep the surface moist, and avoid sowing in hot soil above 80F.
• Slugs and snails: they shred tender leaves overnight. Hand-pick in the evening, set beer traps, or use copper barriers and diatomaceous earth.
• Aphids: rinse them off with a strong spray of water and invite ladybugs with nearby flowers like marigolds and nasturtium.
• Tip burn: brown, crispy leaf edges from uneven watering or heat. Keep moisture steady and grow in cooler conditions.
• Bitter leaves: caused by heat and drought stress. Harvest young, keep soil moist, and pick in the cool morning.