Growing Romaine from Seed Is Easy

I'm guessing you've probably eaten your fair share of romaine lettuce, also known as cos lettuce in other English-speaking parts of the world. It is, after all, one of the four most popular types of lettuce (along with crisp head, butterhead, and loose leaf) and has long been the star of Caesar salads.

And it's popular for good reason. Romaine is one of the hardiest and healthiest salad greens that you can grow. Not only can it withstand both hotter and colder temps than some of the other more tender leafy greens, it's also more durable after harvesting, making it an easy leaf to put on grocery store shelves.

That being said, you haven't really tasted romaine until you've had it fresh from the garden, not trucked in from California or Arizona, where 99 percent of all the romaine found in our grocery stores is grown. Not only are you getting leaves at the peak of their flavor and nutrition when you grow and harvest your own, you're also cutting down on food miles and fuel usage. You're going to get leaves that taste so much better than ones that have been sitting in a plastic box for two weeks.

So, try to romaine calm when I tell you how easy it is to grow one of the most popular kinds of lettuce right in your own backyard (or on a balcony!).

Added bonus: you don't have to worry about all those E. coli and salmonella recalls on the news when you grow your own.

Where to Grow Romaine Lettuce

Romaine lettuce grows well in raised garden beds and in containers.

I love to grow romaine and other salad greens in a little salad garden planter I made from a steel container. Many would-be-gardeners think they have to go big or go home in the garden, when really, there are so many easy and small ways that allow you to get started right away.

Just set your little planter somewhere it'll receive at least 4 hours of sunlight to give you good leaf production. That could even be in a sunny windowsill. (Make sure to rotate your planter every time you water it.)

If you're making your own salad garden planter, make sure to add drainage holes at the bottom if your container doesn't already have them. Lettuce plants don't like to sit in water for too long. Find the complete step-by-step to create your own salad garden planter here.

How to Grow Romaine Lettuce

Lettuce varieties fall into two categories: loose leaf and those that form a head. Romaine produces more and more leaves around a tight center to form a fairly compact head, but as you'll see, you can still harvest from it like you would a loose leaf lettuce plant. (That means you get to enjoy leaves much sooner!)

Here are five things to keep in mind when planting and growing romaine lettuce from seed.

#1: Plant Romaine Lettuce in the Cool Season

Romaine grows really well during the cool season. It loves temperatures between 45 and 75°F (7.2 and 23.9°C), but unlike a lot of other lettuces, romaine can usually tolerate some heat. It's best to grow romaine in the spring and the fall. In the spring, wait until the threat of frost has gone.

You can start romaine from seed in the garden or indoors before your final frost date. If you're starting it indoors, keep in mind that it will be a bit fragile to transplant into the garden later on.

If you’re trying to grow romaine into the warmer parts of the year, plant some taller plants around it to give it some shade. Once it grows too hot outside, your plant will start to produce a milky white substance, which doesn't harm you but will affect the flavor. You'll also notice a change in the plant's shape once the conditions are no longer optimal for growth.

These changes happen because the plant is bolting and focusing only on seed production. When this happens, it's time to toss your plant in the compost bin and start again when the weather gets cooler.

#2: Grow Romaine Lettuce in Nutrient-Rich Soil

You have two options for growing medium for your romaine. You could create a sandy loam soil mix that will appeal to all your leafy greens. If you're not sure what sandy loam soil is, don't worry. You can download my soil recipe here.

If you're looking to simplify, you could also just grow your romaine in 100% compost.

Romaine plants won't require fertilizer if you set them up with great soil from the beginning. If you feel like your plants could use a little nutrient boost, sprinkle some earthworm castings over the soil surface.

#3: Pack in Your Romaine Plants

Lettuce plants are small, even romaine, which you might think of as a bigger lettuce. The roots don't take up much space below ground, and the leaves have a compact, upright growth habit above ground. You can grow at least 9 plants per square foot of garden space as long as you plan to harvest the older, outer leaves regularly. This will ensure your plants still get plenty of air flow.

(If you'd prefer to wait to harvest until you have a full head, then you'll need to give each plant about 81 square inches of space.)

I highly recommend using a planting ruler with small holes along the markings to help you place romaine seeds with precision. You could also make your own or use a measuring tape. These tools will help you plant in nice, long rows if you're planting romaine lettuce seeds strategically.

#4: Protect Your Romaine Lettuce Leaves from Garden Pests

To protect your romaine from pests like earwigs, slugs, cutworms, or even squirrels, it's a good idea to cover it with garden mesh.

The key is to cover your salad garden from the moment you first sow your romaine lettuce seeds. Young plants are particularly vulnerable to pest pressure, but garden mesh will give them all the protection they need from the get-go.

Garden mesh has the additional benefits of helping to lock moisture in your raised beds (which romaine will love) and providing some shade and shelter from strong winds and other harsh weather conditions.

#5: Keep the Soil Consistently Moist

The most important time to pay attention to watering is for the first 2 weeks after you've sown lettuce seeds. Right after sowing, water your seeds in gently. Continue watering every day so that the soil around the seeds stays moist.

After that, you still don't want to let the soil ever dry out completely. Stick your finger into the soil, and if it feels dry about 1 inch down, it's time to water. Overall, the best time to water is in the early morning so your leaves have all the resources they need to survive the warmth of the day.

If your romaine lettuce leaves ever turn yellow, that's a sign you're watering too often. Pull back on the watering time and duration for your salad garden.

Harvest Romaine Leaves from Your Plants Frequently

Romaine needs 70 to 75 days to grow a full head, but you can begin harvesting leaves from the outside of your plant sooner than that.

Treat your growing romaine plant as a cut-and-come-again salad green by cutting leaves one at a time with pruners (or gently twist them off). Always take the oldest, more mature leaves from the outside of the plant to encourage your plant to keep producing new leaves for you from the center.

Give each plant time to recover after a harvest before you cut more leaves. Continue harvesting from your romaine plant this way during the optimal growing window because this is when the leaves will taste their sweetest.

Speaking of the sweetest-tasting leaves, the best time of day to harvest from your lettuce plants is early in the morning. This is when the leaves will be in peak flavor.

Once you're nearing the end of your cool season, you can harvest the entire head of romaine. Grab the leaves like you're gathering hair for a ponytail, and cut the entire plant at the base using a clean knife or a sharp pair of pruners. This is how the heads you purchase at the grocery store were harvested. When you harvest the entire head, you may get one more set of leaf growth from the center of the plant, but it's unlikely you'll get a lot of further production.

Overall, you'll end up getting more leaf production from your plants when you harvest regularly from the outside using the cut-and-come-again method. Harvesting this way allows me to eat a salad from the garden a day for six months of the year.

How to Store Romaine Lettuce

It's always best to harvest only when you can enjoy your leaves right away.

As soon as you harvest leaves, you want to put them directly into a salad spinner or strainer and take them inside to rinse them thoroughly. Spin or pat them completely dry.

Once you're sure the leaves are dry, put them in a sealed container. I like to cover them with a paper towel before closing the container and putting it in the fridge. One great thing about romaine is these leaves last a little longer in the fridge than other more tender lettuces.

What Is the Nutritional Benefit of Romaine?

If you're concerned about eating too much kale or spinach, romaine contains a much smaller amount of oxalate, which can be difficult for those with compromised gut health. And because it's less fibrous and higher in water, it's easier on your digestion. Plus, there's more than 100% of your daily vitamin K needs in a single serving of romaine, not to mention tons of folic acid, vitamin C, and minerals.

When you eat romaine fresh from your garden, the leaves will be packed with more nutrients than those leaves that have been picked in one of only two places in the United States, wrapped in plastic, trucked to your grocery store, and plopped on a shelf to sit for who knows how long.

To enjoy the full goodness of romaine, add it to your sandwiches for a bit of crunch. You can blend it into your smoothies or keep the ribs attached and add the leaves to stews. It's good for so much more than Caesar salads.

Why Does Romaine Lettuce Get Recalled So Often?

If you pay attention to the news, then you know that E. coli breakouts occur at least once a year with romaine lettuce. E. coli is a strain of bacteria that can cause us to get really sick.

Here in the US, we get about 99% of our lettuce from two places: California and Arizona, where temperatures are just right for lettuce plants. Since so much of our lettuce is grown in just two places, when there is an outbreak, they have to tell the entire country to throw away their lettuce because the bacteria from one spot could potentially be spread throughout the entire county. It's almost impossible for farmers to look back and pinpoint where the contamination originated from.

Plenty of veggies can be exposed to bad bacteria, but it's an extra problem with romaine because we don’t often cook it. Romaine is best when it’s fresh and crisp, but that doesn't give us a chance to remove contamination.

With the food system that we've developed, recalls and outbreaks are going to continue to be a problem. The only way to change that is by making our lettuce sources more localized to the customer. For instance, if we had lettuce growers in the Carolinas and in Texas, in addition to California and Arizona, we could better isolate issues.

This is why it is so important to start shopping locally. When you’re buying lettuce from your local farmers, you are cutting down on plastic and food trucking, and your lettuce is going to taste way better. You'll also be promoting more locally sourced foods, which could save us all from having to toss out bags of lettuce in the future.

Is Romaine the Same as Cos?

What we call romaine is cos in many other parts of the world because it was said to have originated on the Greek Island of Cos. Parris Island Cos is actually my favorite romaine variety to grow.

What's Better: Iceberg vs Romaine Lettuce?

Lettuce is good for you no matter what. Romaine lettuce contains tons of beta carotene and has more vitamin A and vitamin K than iceberg lettuce. Iceberg lettuce is more cost-effective to buy and has a longer shelf life than romaine. It has a crispier, crunchier texture.

So, if you're looking for something to stick in a drawer and last a while, iceberg is for you. If you're looking for a lettuce that is more nutrient-dense, romaine is your girl.

Will Romaine Lettuce Regrow After Cutting?

Your romaine plant can keep growing after being harvested if you use the cut-and-come-again method, meaning you take just a couple leaves from the outside of the plant and leave the center of the plant to keep producing. If you cut the entire head of the plant but leave a couple inches of the base in the soil, the remaining base will likely grow new leaves.

You can also regrow romaine lettuce from the cut-off base of the head by placing it in water. Keep in mind that these leaves likely won't be as tasty as the originals.

Grow Your Own Romaine

Lettuces are one of the best plants to start off with in the kitchen garden. They grow quickly, don't take up a lot of space, and provide harvests again and again. Once you fall in love with watching those nutrient-dense leaves grow in so fast, you'll be ready to grow more of your own food.

For more leafy inspiration, check out our top ten salad greens to grow in the garden. If you still don't have your salad garden set up yet, here are the best containers for growing salad greens.

Here's to filling up on lots of romaine in the future!

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