Growing Lettuce in Pots

Recipes for Success: Lettuce (Lactuca sativa)

Habit: Leaf, Head
Cultivars: Numerous cultivars are commonly grown with good success, including

• Green Leaf - Green Ice, Simpson Elite, Black-Seeded Simpson
• Red Leaf - Red Sails, Lolla Rosa, Cherokee, Firecracker
• Boston/Butterhead - Buttercrunch, Kweik, Sylvesta, Pirat
• Head - Ithaca, Summertime, Nevada, Tiber
• Romaine -Parris Island Cos, Red Romaine, Crisphead

Pot Size: Medium
Water: Water the container to maintain a uniform moisture supply during growth. Early watering will insure that the foliage dries out before dark.

Comments: When choosing what type of lettuce to grow, remember that the darker the leaf, the richer the produce in beneficial nutrients. Most gardeners who grow lettuce raise the loose-leaf type, with either dark green or reddish leaves. This type is a fast-growing, long-lasting lettuce used for salads and sandwiches. Butterhead or Bibb lettuce is a loose-heading type with dark green leaves that are somewhat thicker than those of iceberg lettuce. Butterheads develop a light yellow, buttery appearance and are very attractive in salads. A miniature variety of butterhead, Tom Thumb, is very easy to grow and requires a short growing time. Bibb lettuce will develop bitterness if temperatures go above 95 °F.

Romaine or cos is less commonly grown by gardeners but is a very nutritious lettuce that deserves attention. It too is relatively easy to grow, forming upright heads with rather wavy, attractive leaves. Crisphead, also known as iceberg, has a tightly compacted head with crisp, light green leaves. Many gardeners find this type difficult to grow in high temperatures.

Seeds: Plant seeds to a depth approximately twice the thickness of the seed, water, and tamp soil firmly. Keep soil moist but not saturated, and keep pot out of direct sunlight to avoid overheating. Thin to approximately one plant per six square inches for leaf varieties and one plant per foot for head varieties. Leaf thinnings may be used in salads as soon as they are picked.

Transplants: Place in hole no deeper than original root ball and tap around stem firmly.
Soil: The soil should be well-prepared to provide good seed-to-soil contact (when planting seed) and ensure rapid stand establishment. Mulching is effective to control weeds and keep soil temperature cool.
Insects: Commonly encountered insects include aphids, cabbage looper, corn earworm, and leafhoppers.
Solutions: Spray for mites with biologically friendly non-detergent soap mixed with water (1T per gallon). Slugs and snails may be picked off and disposed of by hand.

Diseases: Damping-Off (a fungal condition) affects small plants, which may wilt and die soon after emergence. Other diseases include gray mold, Rhizoctonia bottom rot, and Sclerotinia drop.

Solutions: Use only high quality treated seeds and avoid excessively wet soil and prolonged exposure to cool temperatures, conditions favorable to disease.

Health Benefits: There are many different types of lettuce and related greens but only one truth: The darker the leaf’s color, the more nutritious it is. Beta-carotene is the chief disease-fighting element featured in dark-colored greens. As an antioxidant, it is a potent fighter against certain cancers, heart disease, and cataracts. That lush dark-green color also indicates folic acid, which helps prevent neural-tube birth defects in the early stages of pregnancy. Researchers have also unveiled several other important contributions that folic acid has made to health. It can play a significant role in the prevention of heart disease and cellular inflammation. In fact, most salad greens (and not only lettuce) offer significant sources of vitamin C, potassium, and fiber. Chicory, another good source of vitamin C (a powerful antioxidant), is also linked to the prevention of heart disease, cancer, and cataracts. Some other beneficial salad greens, such as arugula and watercress, are members of the cruciferous family (along with cabbage and broccoli), adding even more ammunition to the ongoing battle against disease and lending a new meaning to the phrase, “Green Revolution.”
Ready for the Kitchen: Most leaf lettuce should be ready to harvest about 75 days after planting. It can be used as soon as plants are 4 - 6 inches tall. Bibb lettuce is mature when leaves begin to cup inward to form a loose head. Cos or Romaine is ready to use when the leaves have elongated and overlap to form a fairly tight head about 6 - 8 inches tall. Harvest in the morning after dew has evaporated. Regular harvests will keep leaf lettuce from bolting. Store in the refrigerator in the coolest area.

Annual Savings: Approximately $45 per year per person on average.

About the Author

D. J. Herda is author of the best-selling book, From Container to Kitchen: Growing Fruits and Vegetables in Pots (New Society Publishing, 2010).

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