How to Grow Romaine Lettuce - The Complete Guide

Romaine lettuce are a rewarding vegetable to grow at home and an excellent addition to any garden. Below we share the basics of growing romaine lettuce in a home garden, as well as common mistakes and considerations.

When to Plant Romaine Lettuce

Romaine lettuce are a frost tolerant vegetable. This means the best time to plant them is mid to early spring, and mid to late summer for a fall harvest. If you’re expecting a late or early frost after planting, protect your romaine lettuce with a blanket of straw or cover them with plastic buckets.

If you live in the U.S., check out the Farmer’s Almanac or the USDA’s Plant Hardiness Zones for more help regarding frost and the best dates for planting in your area.

How to Plant Romaine Lettuce

Plant your romaine seeds directly in the soil of your garden or container at a depth of 0.5 inches (1 centimetre). Seeds can be planted outside or you can germinate them indoors and transplant them later. Typically, romaine seeds take about 1 - 2 weeks to fully germinate.

If transplanting, the best time to move romaine plants outside is when they reach 3 - 4 inches (7 - 10 centimetres) tall or have at least 3 - 4 true leaves.

When planting romaine lettuce in the garden, it’s best to space them 1 - 2 feet (30 - 60 centimetres) away from the nearest plant.

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How to Grow Romaine Lettuce in Pots

The key to caring for romaine lettuce in containers is well draining soil and a pot big enough for their root system. Aim for a pot that is roughly 288 cubic inches (4,719 cubic centimetres) in size. Any old flower pots you have lying around should do the trick.

For more in depth information, check out our full guide on growing romaine lettuce in containers.

How Long do Romaine Lettuce Take to Grow

On average, it takes about 30 - 50 days for planted romaine seeds to develop into a fully mature plant.

How Big do Romaine Lettuce Get

Typically, romaine plants reach about 8 - 12 inches (20 - 30 centimetres) in height. Though this can fluctuate depending on the variety.

How Much Sunlight do Romaine Lettuce Need

Romaine lettuce need 3 - 6 hours of direct sunlight every day in order to thrive. Be careful to place your plants in an area that receives adequate sunlight. Otherwise, they may not mature properly.

How Much Water do Romaine Lettuce Need

Romaine lettuce like well draining soil that is kept consistently moist, but not wet or soggy. The amount of water it takes to achieve this effect will differ depending on the type of soil available to you.

Be sure to water your romaine lettuce on a consistent, steady schedule. This will ensure the plant yields a healthy, uniform crop.

If growing your romaine lettuce in pots, they will need to be watered more frequently than romaine lettuce planted directly in the garden.

You will know your romaine lettuce are in need of more water when their leaves wilt, yellow, and/or the plant begins to droop. But be careful, this can also happen if the plant receives too much water. This is a difficult balance for most novice gardeners. But the more time you spend with your romaine lettuce, the better you’ll be able to gauge how thirsty they are.

How to Harvest Romaine Lettuce

Snip the base of the single romaine leaf that you want to remove with a knife or scissors. It’s best to remove the larger outter leaves first, and leave the smaller leaves to pick once they are ready. This way you won’t damage or kill the plant, and it will keep producing tastey romaine lettuce for you all season.