Purple lettuce, a variant of common lettuce (Lactuca sativa), offers a unique aesthetic appeal to gardens and culinary dishes. Its vibrant hues, from deep burgundy to reddish-purple, distinguish it from traditional green varieties. This leafy green adds color and a mild, fresh taste to meals.
Popular Purple Lettuce Varieties
Popular purple lettuce varieties include: ‘Red Sails’ is known for its frilly, deep reddish-purple leaves and resistance to bolting in warmer weather. ‘Merlot’ is a prominent leaf lettuce, named for its rich, wine-like color, producing large leaves for salads and sandwiches. ‘Sea of Red’ is a cutting lettuce with narrow, lance-shaped purple leaves harvested as needed. ‘Purple Fusion’ is a Summer Crisp variety displaying a purple blush with green underneath, with crunchy texture and thick ribs.
Nutritional Advantages of Purple Lettuce
Purple lettuce provides health benefits due to its distinctive coloration. Its deep purple, red, and blue shades come from anthocyanins, powerful antioxidants that neutralize free radicals and contribute to anti-inflammatory effects. This leafy green also offers essential vitamins and minerals, including Vitamin K, Vitamin A, manganese, folate, and iron.
Growing Purple Lettuce
Cultivating purple lettuce successfully involves attention to site conditions, planting practices, and ongoing care. This cool-season crop thrives in temperatures between 50 to 95°F (10 to 35°C), with maximum growth around 59-64°F (15-18°C). Prolonged temperatures above 86°F (30°C) can cause the plant to “bolt,” leading to a bitter taste.
Site and Soil
Purple lettuce prefers full sun to partial shade, especially in hotter climates where afternoon shade can prevent bolting. The ideal soil is well-drained, rich in organic matter, and has a slightly acidic pH, between 6.0 and 7.0. Incorporating compost or well-rotted manure before planting improves soil fertility and moisture retention.
Planting
Starting purple lettuce from seed can be done directly outdoors two to four weeks before the last spring frost, or indoors six to eight weeks prior to transplanting. Seeds should be sown shallowly, about 1/8 to 1/4 inch deep, as they require some light for germination. When transplanting, space loose-leaf varieties 8 to 10 inches apart in rows 12 to 18 inches apart, or closer for baby greens.
Watering and Mulching
Consistent moisture is important for tender leaves. Water thoroughly weekly, or daily in hot conditions, to keep shallow roots moist. Drip irrigation or soaker hoses deliver water directly, avoiding overhead watering that can cause fungal diseases. A 2 to 3-inch layer of organic mulch, such as straw, conserves soil moisture and suppresses weeds.
Fertilization
Lettuce benefits from a balanced nutrient supply. Before planting, enrich soil with compost and a nitrogen-rich fertilizer for initial growth. If plants show stress, like yellow or wilted leaves, apply a side dressing of compost or a diluted liquid fertilizer. Nitrogen promotes leafy growth, potassium enhances disease resistance, and phosphorus aids root development.
Pest and Disease Management
Manage pests and diseases organically to maintain plant health. Common pests like aphids and leafhoppers can be deterred with insecticidal soap. Remove cutworms by hand. Covering young plants with insect netting creates a physical barrier. Good air circulation, achieved through proper spacing and avoiding overhead watering, helps prevent fungal issues like bottom rot and downy mildew.
Harvesting and Using Purple Lettuce
Harvesting
Harvesting purple lettuce at the right time ensures best flavor and continued production. Leaves are most tender and flavorful when harvested in the morning after absorbing water. Begin harvesting individual outer leaves once about 4 inches long, allowing inner leaves to continue growing. This “cut-and-come-again” method allows multiple harvests from the same plant. Snip outer leaves about an inch above the crown, avoiding damage to the plant’s center.
Culinary Uses
Purple lettuce is a versatile kitchen ingredient, adding color and a fresh, mild flavor to dishes. It is commonly used raw in salads for visually appealing presentations. Beyond salads, it can be incorporated into sandwiches, wraps, or as a bed for grilled meats or vegetables. Its leaves can also be lightly stir-fried with garlic and sauces for a warm side dish, offering a slightly different texture while retaining some crunch.