Lettuce is a cool weather crop, along with other garden favorites such as collards, kale, spinach, Swiss chard, broccoli, cilantro, and cabbage. "Cool weather crops" are those that are more tender, flavorful, and generally successful if they mature while the weather is cool. Many gardeners plant these crops in the early spring, taking advantage of our beautiful spring weather, but these can also be planted in late summer to mature as the weather cools in early fall.
Most garden lettuces will reach maturity, if planted from seed, within 50 to 70 days, depending on the variety. That means that lettuce planting can begin now, to reach maturity just before and in the several weeks following the first frost. The first frost in our area usually arrives toward the end of October or early in November. Some gardeners make two, three, or more plantings of lettuce, to keep the leafy greens coming through the fall and early winter.
According to UGA Cooperative Extension's publication "
Home Garden Lettuce," this particular crop will grow well in most home gardens provided that its basic requirements are met. In addition to the usual garden-veggie requirements of 10-12 hours of sunlight and "fertile sandy loam soils that are well supplied with organic matter," lettuce will grow best with a slightly acid soil pH of 6.0 to 6.5.
Lettuce can be planted in rows or broadcast across the bed. The seeds are very small, and care should be taken to not let them sink too deeply into the soil, so that they are covered by only 1/8 to 1/4 inch of soil that is tamped down lightly with the back of a hoe or with the gardener's hand.
The "Home Garden Lettuce" publication specifies that the crop needs to be fertilized both at planting and again as the season progresses:
At planting time, "In the absence of a soil test, incorporate 3 to 4 pounds of 5-10-10 fertilizer per 100 square feet of garden area." Then, "After the initial fertilizer application at planting, apply 2 pounds of 5-10-15 per 100 square feet of bed each month during the growing season."
If the gardener had a soil sample from the garden tested for nutrients in advance of planting, the gardener should, instead, follow the fertilizer recommendations that came with those test results.
For organic gardens, managing the soil for soluble nutrients requires a different timetable. The Cornell University Cooperative Extension publication
"Production Guide for Organic Lettuce" explains that nutrients are released through the actions of soil-dwelling microorganisms as they decompose organic matter such as compost, animal manures, and green manures that have been incorporated into the soil: "In a long-term organic nutrient management approach, most of the required crop nutrients would be in place as organic matter before the growing season starts." Essentially, this means that, if enough organic matter is in place, much of the needed "fertilizer" is already in the garden.
In an organically managed garden, nutrient release takes place throughout the season, but it happens more slowly in cooler weather and in gardens that are new or newly transitioning to an organic approach. For lettuce, the necessary nutrients "can be supplemented by highly soluble organic amendments such as poultry manure composts or organically approved bagged fertilizer products." Examples of bagged fertilizer products include blood meal, soy meal, and alfalfa meal. Organic gardeners should follow the package recommendations for application of these products.
