Lettuce

Overview:

It's believed that the ancient Egyptians were the first to cultivate lettuce. Along with the Greeks and Romans, the Egyptians would use lettuce as a remedy for stomachache and as a sleep-inducing agent. The Romans introduced it to England, and Christopher Columbus introduced it to the new world.

Planting and Growing:

There are two different types of lettuces that can be grown in the garden. Varieties produce better leaf lettuces, and those that produce better heads (All varieties, if left to grow, will eventually produce a head). Both can be sown indoors 4 weeks before transplanting in mid-spring, or directly sown outdoors when soil is ready to work. Leaf lettuces that will be harvested continuously are best sown directly outdoors and thinned to ½ inch (1.25 cm) apart in long rows. Head lettuce should be planted in diamond patterns to maximize space, giving between 8 to12 inches (20 to 30 cm) between plants.

Lettuce is a cool, weather plant and can be planted early in the garden. It can tolerate light frost, but should be protected with row cover when temperatures dip below 30 degrees F (-1 degree C). Plant seeds every 2 weeks for a constant supply of young lettuce leaves or continuous harvest of heads.

Lettuce should be grown quickly to ensure the leaves are sweet and don't grow bitter. Prepare the soil in the fall by turning in 1 inch (2.5 cm) of good compost. Fertilize every few weeks after transplanting with a good, nitrogen riche fertilizer.

Lettuce should be watered lightly in early spring, until warm temperatures dry the soil. Keep soil moist from that point, but not wet. Lettuce has shallow roots, so cover lightly with mulch 2 inches (5 cm) deep. It is also best to plant with other vegetables that will offer some shade in the hot, summer months.

Harvesting and Preserving:

Known as the foundation of a good salad, lettuce has become a garden favorite. Lettuce, grown in the garden, is richer in taste and nutrients. Harvest lettuce leaves and heads in the morning, before the sun begins to warm the plant. Lettuce is at its peak of flavor in the morning, and will retain more sugars if picked in the morning. It will store for about a week in the refrigerator, but is best eaten the same day it is picked.

Lettuce should reach harvestable age in 4 to 6 weeks. Harvest the outer leaves with scissors or a sharp knife about 1" (2.5 cm) above the soil. Continue harvesting leaves until they become bitter, and then pull the plant. Not to worry. If plants were planted in succession, there will be new plants ready to harvest. Head lettuce is ready to harvest if the head is tight and about 4 to 6 inches (10 to 15 cm) in diameter.