Romaine Lettuce Plant Care

Romaine Lettuce (Lactuca sativa var. longifolia) belongs to the family. Romaine Lettuce is native to Europe, Asia, Africa. Romaine Lettuce is also known as Cos Lettuce, Asparagus Lettuce, Lactuca sativa var. longifolia.

Romaine Lettuce displays an upright, compact growth habit, reaching up to 1 ft tall with a spread of approximately . Romaine Lettuce produces none.

Leaf size: approximately 8 inches.

Water a young or newly planted Romaine Lettuce every 3–7 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established shrubs mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.

Romaine Lettuce thrives in full sun.

Lactuca sativa var. longifolia tolerates temperatures of 55–75°F. Romaine Lettuce prefers humidity levels of 50–70%. A pebble tray or humidifier helps maintain adequate moisture around the plant.

Well-draining soil mix. Good drainage is essential for Romaine Lettuce to prevent waterlogging, which leads to root rot and fungal issues.

Feed Romaine Lettuce every 2 months during the growing season with a balanced, slow-release fertilizer at the rate on the label. Established shrubs in good soil often need little extra feeding, so let weak growth or pale foliage guide you.

Stop feeding by late summer so new growth can harden before winter.

The PlantoScan app can remind you when to water and when to fertilize each plant.

Choose a spot with full sun and well-draining soil mix. Avoid low spots where water collects after rain.

Romaine Lettuce is suited to USDA Zone 8a – 10b.

Plant container-grown or balled-and-burlapped shrubs in spring or early autumn, setting the root flare at soil level, and water well after planting.

Prune Romaine Lettuce while it is dormant in late winter: first remove dead, damaged and crossing branches, then thin lightly for shape.

If it flowers in spring, prune right after flowering instead so you don't remove next year's buds. Never take off more than about a quarter of the shrub in one year.

Romaine Lettuce is hardy down to USDA zone 8a, so once established it can stay outdoors through winter in that zone and warmer ones.

Water deeply in late autumn before the ground freezes, and spread a 5–8 cm (2–3 in) layer of mulch over the root zone, keeping it away from the trunk.

Young and container-grown shrubs need extra protection: roots in a pot freeze much more easily than roots in the ground.

Romaine Lettuce can be propagated through seeds. Similar propagation techniques also apply to prickly lettuce plant care, which shares the same genus.

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Romaine Lettuce is susceptible to aphids, slugs, snails. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Romaine Lettuce grows outdoors in USDA Zone 8a – 10b. It survives winters down to planting zone 8a. Romaine Lettuce is native to Europe, Asia, Africa.