Lettuce is a cool-weather plant that will do best if sown either very early in spring or very late in summer. Avoiding the heat of the summer and maintaining a constant growing temperate that falls between 60 and 65 degrees Fahrenheit actually favorably impacts the plant's taste and abundant growth. Prior to getting out into the yard, the hobbyist should consider the kinds of lettuce she wants to grow: Iceberg lettuce, for instance, is more labor-intensive to grow and tend than butterhead, leaf or romaine varieties.
Rake the soil and remove weeds. Since lettuce has very shallow roots, it cannot easily compete against other plants that might also have superficial root systems. After clearing the soil of the garden bed, test its pH level. Lettuce thrives in soil with a pH range from 6.0 to 6.7.
Augment the soil as needed, based on the pH test. Working-in compost or commercially available 10-20-20 fertilizer reduces soil pH levels and ensures that the soil offers sufficient nutrients to the plants. This encourages strong growth right from the start. For increasing the soil pH, lime supplementation is a good solution.
Dig several straight lines in the planting area with a hoe. These furrows now separate several raised planting areas. Since lettuce seeds germinate at temperatures that are between 70 and 75 degrees Fahrenheit--and since slightly raised flower beds provide for slightly raised soil temperatures--this step eliminates the need to start seedlings indoors.
Plant lettuce seeds in the prepared rows at nine- to 12-inch intervals. Simply create a quarter- to half-inch indentation with a finger to make the hole. Cover the seeds with a thin covering of augmented soil.
Water the lettuce seeds. Remember that lettuce has very shallow roots and therefore benefits from more frequent but less lengthy watering sessions than more deeply-rooted plants would. In fact, overwatering is a major contributor to leaf-tip burn and other diseases. A good solution can be the use of soaker hoses or drip irrigation systems within the raised flower beds.
Keep an eye out for diseases and pests. Growing lettuce is susceptible to aphid and slug infestations as well as damping-off. The latter is a fungus-caused ailment that may prevent germination or kill off new seedlings. Using commercially available lettuce seeds that are treated with an anti-fungal chemical reduces this risk. Rely on organic means for removing aphids, such as rinsing the lettuce with water and mild, organic dish soap. Sprinkle wood ashes around the plants to discourage slugs.