(For details on growing many other vegetables and fruits, visit our Crop at a Glance collection page.)
From baby leaf lettuce to big, crisp heads, growing lettuce is easy in spring and fall, when the soil is cool. Leaf color and texture vary with variety. All types of lettuce grow best when the soil is kept constantly moist, and outside temperatures range between 45 and 75 degrees Fahrenheit.
Types of Lettuce to Try
Loose-leaf varieties grow tender leaves in dense rosettes, but seldom form crisp inner heads. Some loose-leaf lettuce varieties have superior heat tolerance.
Butterheads and bibb types quickly form small heads of leaves with stout, crunchy ribs. Some varieties have superior cold tolerance.
Romaine lettuce has elongated leaves with stiff ribs. Romaines often tolerate stressful weather better than other types of lettuce.
Crisphead lettuce includes familiar iceberg types, as well as lush and leafy Batavian, or French Crisp, varieties which have great flavor and color, and are easy to grow.
For more information about types of lettuce and our recommended varieties, see our Lettuce at a Glance chart.
When to Plant
In spring, sow lettuce in cold frames or tunnels six weeks before your last frost date. Start more seeds indoors under lights at about the same time, and set them out when they are three weeks old. Direct seed more lettuce two weeks before your average last spring frost date. Lettuce seeds typically sprout in two to eight days when soil temperatures range between 55 and 75 degrees.
In fall, sow all types of lettuce at two-week intervals starting eight weeks before your first fall frost. One month before your first frost, sow only cold-tolerant butterheads and romaines.
How to Plant
Prepare your planting bed by loosening the soil to at least 10 inches deep. Mix in an inch or so of good compost or well-rotted manure. Sow lettuce seeds a quarter of an inch deep and 1 inch apart in rows or squares, or simply broadcast them over the bed.
Indoors, sow lettuce seeds in flats or small containers kept under fluorescent lights. Harden off three-week-old seedlings for at least two or three days before transplanting. Use shade covers, such as pails or flowerpots, to protect transplants from sun and wind during their first few days in the garden.
Harvesting and Storage
Harvest lettuce in the morning, after the plants have had all night to plump up with water. Wilted lettuce picked on a hot day seldom revives, even when rushed to the refrigerator. Pull (and eat) young plants until you get the spacing you want. Gather individual leaves or use scissors to harvest handfuls of baby lettuce. Rinse lettuce thoroughly with cool water, shake or spin off excess moisture, and store it in plastic bags in the refrigerator. Lettuce often needs a second cleaning as it is prepared for the table.
Lettuce varieties are open-pollinated, so you can save seeds from any plants you like. Be patient as your strongest plants develop yellow flowers followed by ripe seedpods. Stake plants if necessary to keep the ripening seed heads from falling over. Gather the dry seed heads in a paper bag, and crush them with your hands. Winnow or sift to separate the seeds from the chaff, and store the seeds in a cool, dry place for up to a year. In some climates, plants grown in spring will reseed themselves in fall.
Pest and Disease Prevention Tips
- Slugs chew smooth-edged holes in outer leaves. Collect them with a gloved hand during drizzly weather, or trap them in pit traps baited with beer. You also can spray cold coffee on slug-infested plants to stop feeding.
- Aphids sometimes feed in groups between the folds of lettuce leaves. Try rinsing them away with a spray of cool water. Natural predators such as syrphid fly larvae often bring the problem under control.
- Prevent soilborne diseases by growing lettuce in the same spot no more than once every three years.
Growing Lettuce Tips
- As the seedlings grow, thin leaf lettuce to 6 inches apart, thin romaines to 10 inches and allow 12 inches between heading varieties. After thinning, mulch between plants with grass clippings, chopped leaves or another organic mulch to deter weeds and retain soil moisture.
- Replace old lettuce seed yearly, because low germination is usually caused by dead seeds. Expect spotty germination from lettuce seeds that are more than one year old.
- In late winter, grow lettuce inside a cold frame or plastic tunnel. Seedlings often survive temperatures below 20 degrees when they are protected with sheet plastic or glass.
- For extra flavor from your salad bed, sprinkle in a few seeds of dill, cilantro or other cool-season herbs.
- If your garden is small, try miniature lettuce varieties, such as ‘Tom Thumb’ or ‘Minetto.’
- Should hot weather hit just as crisphead lettuce is reaching its peak, cover the plants with a shade cover made from lightweight cloth (such as an old sheet) held aloft with stakes. If possible, cool down the shaded plants by watering them at midday.
- Never allow the soil to dry out while lettuce is growing. In most soils, you’ll need to water lettuce every other day between rains.
- Perfect lettuce does not last long in the garden, especially when the weather gets hot. Harvest lettuce when conditions are good, then store it in the refrigerator.
In the Kitchen
Bumper crops of lettuce can’t be preserved, so plan ahead for daily salads when lettuce is in season. Stock up on big flavor toppings such as olives, dried fruits, nuts and smoked salmon. Be generous with snippings of fresh herbs as you create original salads. Lettuce rolls stuffed with grain or meat mixtures, held together with toothpicks, make a great appetizer. Dark green or red lettuces have more vitamin A than varieties with pale leaves.
Contributing editor Barbara Pleasant gardens in southwest Virginia, where she grows vegetables, herbs, fruits, flowers and a few lucky chickens. Contact Barbara by visiting her website or finding her on Google+.