Lettuce is a vegetable that can be grown year-round, though it tends to grow better in cooler weather. That is not to say that lettuce cannot be grown in spring or summer. It can. However, heat can cause lettuce to ‘bolt’. Bolting occurs when heat causes a period of rapid growth. Instead of diverting its resources into making leaves, the lettuce directs its energy into rapid flower and seed production. The lettuce develops a flowering stalk on its top. The lettuce leaves become tough and often develop a bitter taste. Bolting can be temporarily halted by frequent cutting or removing of the lettuce leaves as soon as they are large enough for consumption.
For best results, plant lettuce early in spring when the temperature is mildly warm. Lettuce can be planted again in late summer or early fall when the air is cool, and the soil temperature is still warm. The traditional rule of thumb, “plant early and plant often” for lettuce can also be said as “plant late and plant often”.
Lettuce comes in numerous shapes, sizes, and textures that you can grow yourself. Consider the oblong shape of Romaine type lettuce or the round shape of lettuce that forms a ‘head’. There are also the leafy ‘cut and grow’ varieties that provide an almost endless supply of lettuce! For every leaf you cut, it seems like two more grow back! Lettuce comes in different textures too. Not all lettuce varieties have a crunchy quality. Some types of lettuce have a silky consistency, whereas others have a butter-like quality.
Lettuce seeds can be sown directly into the soil when soil temperature is between 40 – 80 degrees. Seeds should be sown about 1/8 of an inch deep. Loose leaf or cut and grow type can be sowed about 1 inch apart. However, heading types, that form a ‘head’ of lettuce should be spaced further for adequate room to grow at about 8 – 12 inches apart.
Size, shape, and texture are not the only deciding factors when choosing which lettuce seeds to sow. Consider the nutritional content as well as the health benefits. Deeply colored lettuce is nutritionally superior compared to common, iceberg type, lettuce. Dark colored lettuce typically contains more Vitamin A, Vitamin C, and Vitamin K. Dark colored lettuce is also rich in Carotenoids, such as Beta-Carotene. Carotenoids are the yellow, orange, and red pigments found in plants, including dark, green, leafy lettuce. Evidence suggests that diets high in vegetables containing Carotenoids may help prevent cancer. Other health benefits of a diet high in Carotenoids include a lower risk of coronary heart disease.
The amount of Vitamin A varies in lettuce. Depending upon the type, a large leaf of butter-head type lettuce contains about .025 mg of Vitamin A whereas a darker colored Romaine type lettuce may contain about 0.122 mg of Vitamin A. The recommended dietary allowance of Vitamin A is about 0.7 mg for women and 0.9 mg for men. Because of the role Vitamin A plays in regulating cell growth, several studies have examined the association between Vitamin A and preventing cancer. Some studies indicate that Vitamin A may help reduce the risk of cancer, but more research is needed.
A large leaf of lettuce, again depending upon type contains 0.6 to 2.2 mg of Vitamin C . The Recommended Dietary Allowance of Vitamin C is 90 mg per day for men and 75 mg per day for women. Evidence suggests that higher consumption of fruits and vegetables is associated with lower risk of most types of cancer, perhaps, in part, due to their high vitamin C content. Vitamin C can limit the formation of carcinogens and, through its antioxidant function, possibly help prevent cancer.
Large leaves of lettuce contain anywhere from .015 mg – .03 mg of Vitamin K. The Recommended Dietary Allowance of Vitamin K for adults is .12 mg for men and .09 mg for women. Dark, green leafy vegetables are known as great sources of this nutrient which is essential for normal blood clot formation, known as hemostasis.
Nutrients are best obtained from diet versus nutritional supplements. Pills and supplements do not provide the same health benefits or produce the same results as obtaining them from dietary sources. Germinating your own lettuce provides you with a dietary source of cancer-fighting nutrients right outside your door! Growing lettuce has many other advantages too. Think of the time and money you may save by avoiding unnecessary trips to the grocery store. Growing your own lettuce expands your selection to include gourmet types of various shapes, colors, and textures. Raising your own fresh produce always empowers you to be in charge of any chemical fertilizers, herbicides, or pesticides that are used, making you your own organic farmer!
On a final note, remember that while lettuce and salads are healthy, some salad dressings can literally drown out all of those positive health benefits. Check the sodium content of your salad dressing. Many commercial salad dressings are sodium laden. Select a salad dressing that follows The American Heart Association recommendations of no more than 2,300 mgs of sodium per day. Strive for an ideal goal of no more than 1,500 mgs per day. Following these recommendations will significantly improve your blood pressure and may reduce your risk for having a stroke. For an added health benefit, make a home-made olive oil and vinegar dressing! Olive oil may help increase the bio-availability of the fat soluble Carotenoids found in lettuce.
Be an organic, wellness warrior! Growing your own affords you the opportunity to grow nutritionally superior lettuce!
The Nurse Farmer ™