Romaine or “cos” lettuce is a popular variety of lettuce that is hailed for its flavor, nutritional content, and its versatility; it’s also easy to grow. It grows in tall heads of sturdy leaves that offer a great crunch when eaten. It’s also quite durable, can easily withstand heat, and is quite easy to care for. Romaine lettuce is named for the Romans, who probably imported the leafy green veggie from Greece of Arabia.
In regard to nutritional content, romaine lettuce offers most of the benefits that the majority of dark green leafy greens provide, including antioxidants, fiber, and trace minerals. It’s also quite easy to grow. Whether you’re an experienced cultivator or a novice, if you’re interested in adding romaine lettuce to your garden, keep on reading for some helpful tips and information.
About Romaine Lettuce
- Unlike most varieties of lettuce, Romaine is heat-tolerant.
- In American English, it’s known as “romaine”, while in British English, it is referred to as both “romaine” and “cos” lettuce. Several dictionaries have traced the name “cos” to the Greek island of Cos, which is where it is believed the lettuce was first grown; however, others have linked the word “cos” to “khus”, the Arabic word for lettuce.
- It is said to have been introduced to Western Europe by the Romans, and it is believed that the Romans were introduced to the lettuce by the Greeks.
- In Italian, romaine lettuce is called “lattuga romana” and in French, is it called “laitue romaine”. Both the Italian and French names translate to “Roman lettuce”; hence why it has been dubbed “romaine”, the North American name for the lettuce.
- Romaine lettuce is commonly used as a salad green. It is the basis of the popular Caesar salad. It is also a common ingredient used in Middle Eastern cuisine.
- Like other types of lettuce, romaine can be cooked; for instance, it can be made into soup or braised.
- The leaves – particularly the older outer leaves – feature dense ribs, and usually contain a milky-like substance that is responsible for giving the lettuce the bitter, herb-like taste that it is famous for.
- Romaine lettuce offers several nutritional benefits. It’s rich in essential vitamins, minerals, and nutrients, including vitamin A and vitamin C, which are powerful antioxidants that play a crucial role in maintaining the function of several bodily functions and organs, as they combat free radicals, which can lead to a variety of health complications if in high levels, such as arthritis, heart disease, and even cancer. It’s also rich in vitamin K, calcium, potassium, phosphorus, and magnesium.
- While it’s rich in nutrients, romaine lettuce is low in calories, carbohydrates, and fat. One cup of romaine lettuce (around 47 grams) contains approximately 8 calories, 1.5 grams of carbohydrates, and 0.1 grams of fat.
Romaine Lettuce: An Overview
- Romaine lettuce is (Lactuca sativa L. var. longifolia) is a variety of garden lettuce. It grows in a tall head of robust dark green leaves that feature firm ribs along the center.
- While most types of lettuce are sensitive to heat, romaine lettuce tolerates heat well. While all varieties do of romaine lettuce do can withstand heat, three varieties, in particular, tolerate it best: Jericho, Sparx, and Coastal Star.
- Though it can withstand heat well, romaine lettuce does best when it is grown in cooler climates, and it prefers moisture-rich soil.
- When exposed to too much sun, bolting can occur, meaning that they can run to seed too early, rendering them unusable.
- Romaine lettuce forms tall, tight bundles of thick leaves that can reach up to 20 inches tall, and it takes about 65 to 80 days to reach maturity.
- Because the root system is shallow, most varieties of romaine lettuce grows well in both the ground and in containers.
Growing Romaine Lettuce
Generally speaking, romaine lettuce is pretty easy to grow. It’s a cool-weather crop, so it can be grown both in the spring and the fall. The seeds grow quickly – about 10 days after they have been planted – and they germinate best in temperatures that range from 55 to 65 degrees Fahrenheit. This crop grows best in full sun and is heat-tolerant; however, do keep in mind that, as mentioned above, excessive exposure to heat or intense sun can cause the plants to bolt to seed or can cause the leaves to wilt. For an early, it’s best to start the seeds in flats four weeks before the final frost and then transplant them outdoors during mid- to late-spring. If you intend on growing in the summer, choose a location that receives partial shade or one that has a eastward sun exposure, which will help to prevent the potential negative effects of excessive heat and sun exposure.
While romaine lettuce grow in a variety of soils, it does best in well-drained, loose, cool soils that receive ample amounts of moisture and have a pH of 6.2 to 6.8, as it is sensitive to low pH levels. To promote tender, tasty leaves, add plenty of organic compost matter to the soil, which should be amended before planting the seeds.
For very early plantings, use row covers to protect the lettuce from the cold and from insects. Row covers that are supported by hoops will shade the plants when the warm weather arrives. Because romaine lettuce has a shallow root system, the soil must be kept moist, otherwise the plants will wilt and perish. Water lightly, but on a regular basis and apply mulch over the root systems to lock moisture in the soil and to suppress weed growth. To promote faster growth, fertilize with a fish emulsion type of fertilizer that is low in nitrogen, as high levels of nitrogen can make the greens too bitter. If you intend on planting romaine lettuce in the fall, plan your crops so that they will reach maturity at about the time the first frost usually occurs in your location, as mature plants are not as tolerant to freezing as seedlings are.
Planting Romaine Lettuce
Planting romaine lettuce is pretty easy. For spring crops, direct seed or transplant romaine lettuce in early spring, when the soil can start to be worked. Give yourself an early start by working compost or manure into the soil, then rake the soil and compost or manure mixture so that it’s smooth, creating a fine seedbed that will be ready to accept your romaine lettuce seeds in the spring. Keep in mind when planting that in order to germinate, seeds must receive light, so sowing at a very shallow depth and covering with a thin layer of growing substrate is recommended.
When direct seeding romaine lettuce, sow the seeds about 1/8 of an inch deep, 1 inch apart, with about 12 to 18 inches between rows. When two or three true leaves have appeared, thin 6 to 10 inch spacings for all varieties of romaine lettuce, and 12 inch spacings for crisphead varieties. If you prefer, you can broadcast seeds, which is ideal for looseleaf varieties of romaine, in patches rather than rows.
For transplants, sow romaine lettuce seeds in 1 inch cells about 4 weeks before you intend on transplanting outdoors. To harden seedlings, minimize moisture and temperature about 3 days prior to transplanting; when hardened, the seedlings should be able to survive temperatures as low as 20 degrees F. For crispead varieties of romaine lettuce, transplants should be spaced 12 inches apart in rows that are 18 inches apart. For other varieties of romaine lettuce, transplants should be spaced about 6 to 10 inches apart in rows that are about 12 to 18 inches apart.
Watering Romaine Lettuce
Romaine lettuce can does best in wet, well-draining soil. As such, the plants should be watered on a regular basis; however, when watering, do keep in mind that the root systems of these plants are very shallow, so when watering, you should water gently. If the water is applied too powerfully, the roots can be damaged. In order to retain moisture in the soil, apply mulch around the plants.
Propagating Romaine Lettuce
Romaine lettuce is easy to regrow from cuttings. To do so, all you need is the bottom of a stalk of lettuce to enable the root system to spread. To propagate, cut off the bottom of a bunch of lettuce; it shouldn’t be too short, but it should be long enough that it can be easily planted. Soak the bottoms by setting them in water at least overnight; however, several days are recommended. Prepare soil as per the tips recommended above in a location that receives ample sunlight, then place the soaked bottoms of the cutting into the ground. Water the cuttings and cover with mulch to lock-in moisture.
If you’re interested in growing a healthful, tasty, versatile veggie, romaine lettuce is a great choice. It’s very sturdy, versatile, and easy to grow; plus, it’s tasty, can be consumed in a variety of ways, and is rich in vital nutrients. By following the tips recommended above, you should have no problem growing a successful crop of romaine lettuce.