Lettuce

Growing

To keep lettuce from becoming bitter, keep the garden cool. As temperatures rise, the plant may begin "bolting," rapidly producing a flower stalk that ruins the flavor of the leaves. The plant is hardy, but avoid overcrowding seedlings, as tight spacing can invite fungal diseases like powdery mildew or gray mold, and make the crop more susceptible to pests.

Check young plants for pests. Cutworms slice through seedlings at the soil line, while aphids and leafhoppers can cause leaves to appear yellow, distorted, or pale. Flea beetles leave small holes and leafminers create winding tunnels. If you see stunted growth or yellowing, check your soil for nutrient deficiencies or the presence of wireworms and nematodes.

Harvest lettuce when the leaves are at your preferred size, but before the plant reaches maturity and flowers. Since the leaves do not continue to ripen once picked, harvest them ready for use. Keep the leaves unwashed before storing them in the fridge. A surplus can be blanched and frozen for later use in soups or stir-frys.