Romaine lettuce is an easy-to-grow cool weather crop that provides two harvests per growing season.

Romaine lettuce is an annual plant native to the Mediterranean region and the Middle East.

It has been grown for almost 5,000 years and is a cool-weather crop that is sown in the spring and fall.

In British English, romaine lettuce is known as cos lettuce.

Romain lettuce can deal with a light freeze and may survive through one or two hard freezes but it will not be able to survive temperatures around 25 degrees Fahrenheit or lower.

HOW TO PLANT ROMAINE LETTUCE

Romain lettuce is best grown in well-drained soil with full sun and a soil pH range of 5.5 through 6.5.

They can be sown straight into the soil after the last frost or as I prefer they can be started 8 to 10 weeks before the last frost indoors using a cardboard seed starting tray.

They are best planted 8 to 12 inches apart and each row should be about 12 inches apart for thicker-leaf varieties and 4 inches apart for thinner-leaved varieties and about 1/8 of an inch deep.

You can start them indoors using cardboard seed starting containers and transplant them when the soil is workable in early spring.

If you are short on space then they can be grown in potting containers that can be placed anywhere or they can be put on shepherd’s hooks.

FERTILIZING AND WATERING

To avoid any possible issues of over-fertilizing your lettuce, you should test your soil before adding any fertilizers.

Romaine lettuce is best fertilized every two weeks with a balanced fertilizer such as 10-10-10 or a homemade liquid fertilizer.

They prefer consistently moist soil but not soaked and because they have shallow root systems, they don’t need to be water deep.

BLOOMS

Romaine lettuce blooms appear from a stem that shoots up from the center of the plant with a cluster of small yellow blooms.

The term bolting is a term used when a plant goes to seed for the next season and when romaine lettuce bolts the leaves become bitter and tough.

HARVESTING

Romain lettuce is ready for harvesting in 70 – 75 days after the seeds have been sown into the soil.

Harvesting should be done with sterilized gardening shears or a gardening knife.

As the plant is growing the outer leaves can be arrested allowing the center of the plant to continue growing.

Another method is to cut the lettuce from the base of the plant leaving at least one inch of the base above the soil.

With continued watering, the plant will regrow and be ready for another harvest in 50 – 60 days.

PROPAGATING

Romaine lettuce is an annual plant, therefore propagating them through seed is the only way and some plants should be allowed to go to seed for the following season.

Seeds need to mature properly, the seed coating needs to dry and cure, and they need a rest period prior to planting. Waiting until the seeds have fully cured is the best method of vegetable seed growing.

PESTS

Romaine lettuce has many pests that feed on them but using natural methods such as attracting predators and using natural insecticides such as essential oils, diatomaceous earth, or insecticidal soap will keep your pest control organic.

• Aphids
• Armyworms
• Flea beetles
• Darkling beetles
• Thrips
• Whiteflies
• Crickets
• Grasshoppers
• Slugs
• Snails
• Weevils
• Nematodes
• Leaf miners
• Corn earworms
• Garden symphylans

DISEASES

Romaine lettuce that is planted close together can develop mold and mildew issues during times of high humidity.

If this is the case then preventive measures may need to be taken.

• Downy mildew
• Bottom rot
• Leaf spot

VIRUS

Plant viruses are spread by insects feeding on the plant and transferring the virus, through the wind, water droplets spreading a virus from one plant to another, or damage to the plant through propagation or harvesting.

• Lettuce mosaic virus
• Tomato spotted wilt virus

VARIETIES

There are several different varieties that are available in different colors, shapes, and sizes of foliage.

CIMMARON ROMAINE LETTUCE

Cimmaron romaine lettuce is an heirloom variety from the 1700s, it is also known as red romaine, and is heat-resistant.

• Plant size – grows to about 12 inches wide and 12 inches wide
• Foliage – large reddish-purple leaves
• Days to germinate – 6 to 10 days
• Days to harvest – about 65 days for mature leaves

PARRIS ISLAND ROMAINE LETTUCE

Parris island romaine lettuce is a hybrid variety that is named after Parris Island off the coast of South Carolina where it was cultivated.

• Plant size – grows to about 12 inches wide and 12 inches wide
• Foliage – large green leaves
• Days to germinate – 7 to 15 days
• Days to harvest – about 65 days for mature leaves

FORELLENSCHLUSS ROMAINE LETTUCE

Forellenschluss romaine lettuce is an heirloom German variety.

• Plant size – grows to about 15 inches wide and 6 inches wide
• Foliage – large green leaves with dark red speckles
• Days to germinate – 7 to 15 days
• Days to harvest – about 70 days for mature leaves

DE MORGES BRAUN ROMAINE LETTUCE

De Morges Braun romaine lettuce is a variety from Switzerland.

• Plant size – grows to about 15 inches wide and 18 inches wide
• Foliage – large green leaves with dark red ruffled edges
• Days to germinate – 7 to 15 days
• Days to harvest – about 65 days for mature leaves