Head Lettuce (Iceberg Type)
Light requirements: Full sun to part shade. Protect plants from strong spring or afternoon sun in warmest regions.
Planting: Space 6 to 18 inches apart, depending on lettuce type. (Read the stick tag that comes with the plant for specific spacing recommendations.)
Soil requirements: Lettuce needs moist but well-drained, nutrient-rich soil. Amend soil with compost, blood meal or other organic matter prior to planting. Fertile soil helps fuel fast, tender leaf development. Soil pH should be 6 to 7.
Water requirements: Keep soil consistently moist throughout the growing season — that is the key to tender leaves. Mulch soil to reduce water evaporation and keep lettuce clean from splashing soil.
Frost-fighting plan: Lettuce thrives in cold weather—established plants tolerate light frost (28 to 33ºF), and some types even withstand lower temperatures. Frost sweetens leaf flavor. It’s a good idea to protect newly planted seedlings from late spring or early fall frosts by covering plants with a frost blanket.
Common issues: Pests to watch out for include aphids, slugs, and small green caterpillars.
Various fungi can attack leaves during rainy weather. Once flowers begin to form, leaf flavor becomes bitter; harvest remaining leaves immediately.
Harvesting: Harvest leaves as soon as they’re large enough to eat. Pick baby leaves for salads, or wait for maturity. To extend the harvest, pick outer leaves first and allow center leaves to enlarge. For leaf lettuces, consider using a cut-and-come-again method. Cut the entire plant at the base, leaving a short stub to resprout. If harvesting frosted or frozen lettuce, allow leaves to thaw out before picking.
Storage: Refrigerate unwashed leaves wrapped in dry paper towels in a loosely closed plastic bag. Leaves store from 5 to 10 days, depending on type.
For more information, visit the Lettuce page in our How to Grow section.
- Calories: 10
- Carbohydrates: 2g
- Dietary fiber: 1g
- Sugars: 1g
- Protein: 1g
- Vitamin A: 7% DV
- Vitamin K: 22%
- Folate: 5%
- Manganese: 4%
Like all lettuces, iceberg is very low in calories and composed of over 90% water and as such is a good ingredient in a calorie-cutting diet. The darker leaf lettuces and romaine pack a heavier load of nutrients than the lighter colored head lettuces, but iceberg can still claim to have a fair amount of folate – a B vitamin that helps fight heart diseases and strokes – and vitamin K, important not just in blood coagulation but in bone health, especially helpful in lowering the incidence of hip fractures. So if you love that crunch of iceberg, go ahead and enjoy it. Just add a row of romaine and other dark-leafed lettuces to your garden and increase the nutrient power of your salads.