How to Grow Romaine Indoors

There are few things more refreshing than a crisp, fresh salad—especially if you grew the lettuce yourself. If you’re thinking of starting your own indoor garden, romaine lettuce should definitely be one of the vegetables you should consider. Romaine, known in some places as cos lettuce from its origin on Kos island in Greece, is one of the most common and well-known types of lettuce. With its versatility in dishes and delicious flavor, you’ll find yourself reaching for your home-grown romaine often.   Ready to cool down from the sizzling summer by concocting refreshing Mediterranean salads or even your homemade Caesar salad? Gardyn’s Home Kits are equipped to cultivate a long list of vegetables, fruits, and vegetables all year round. Discover a new gardening solution that is adapted to you. See which model is right for you.


7 - 10 DAYS




3 - 5 WEEKS

Table of Contents

Care & Harvest

🌡️ Temperature

Lettuce prefers cooler temperatures (60-70F), and if placed in higher temperatures, it will turn bitter, bolt, and flower early.

✂️ Pruning

Check the roots monthly and trim any that are brown or extending past the yPod

🥬 Harvest

Lettuce can be picked as individual leaves or harvested as a full head. For ongoing harvest, once the leaves are 4 inches tall, snip the outer leaves an inch above the base of the plant and let the inner leaves continue to grow and mature. Do not cut more than one-third of the plant if you want it to keep growing.

Why Grow Romaine Indoors?

It’s easier than you’d think to grow romaine at home, and there are many benefits that come from harvesting it yourself. While romaine is commonly found year-round in grocery stores, the nutritional content and flavor is lower quality than what you would get when growing it at home.

Fresher Produce

Romaine grown in your own home is fresher and more reliable than what you may buy conventionally at your supermarket. You can harvest it as soon as it’s ripe and not need to worry about wilted leaves bringing down the quality of your salads. Say good-bye to pesticides and the big question mark surrounding where your store-bought lettuce comes from.

Nourishing Your Health

Home-grown plants aren’t just tastier—they’re healthier, too. Freshly-picked produce retains most of its nutrients so the romaine you grow and harvest yourself will be better for you than what you find at any grocery store.

Less Chance For Disease And Pests

A vegetable grown indoors is less likely to become infested with garden pests looking to make a meal of your crops such as snails or slugs. And since you’re able to monitor the soil and ensure your romaine is getting the nutrients it needs, they’re also less prone to diseases that have the tendency to affect commercially-grown produce found in stores.

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Bite sized superfood packed with nutrients and loaded with flavor. Go from seed to harvest in just one week.

What Do You Need To Grow Romaine Indoors?

Romaine lettuce can be grown in the comfort of your home with just a few supplies. With the best seeds as well as the required light, soil, and temperature control, romaine will flourish right in your kitchen, making cooking with it a breeze, and only in a matter of weeks.


Romaine seeds are available from a variety of places—there’s even a number of online plant stores that will ship seeds directly to your door. If you prefer to sow your romaine from seedlings, however, it’s best to go to a local nursery. Seedlings may be best if you enjoy having harvestable romaine sooner, and you have to worry less about whether or not the seeds will germinate.


Soil will be the base of your indoor romaine garden, so finding the right kind is important. Romaine prefers loose soil that drains well—this will prevent your plants from getting root rot. High-quality, loamy potting soil with proper nutrients is best for your lettuce to truly thrive.


Romaine is unique as a lettuce variety because it’s more tolerant of shade—it can grow with just around six hours of direct sunlight per day, making it perfect for indoor gardens. But if you know your plants won’t be getting that amount of sun, a lighting system can supply your romaine lettuce with the light it needs to grow. Most indoor gardeners choose LED strips, but since romaine requires a lower amount of light fluorescent bulbs can also be used.


Keeping your romaine cool is key in helping it flourish. Romaine is a very temperature-sensitive plant, and if it grows in an environment that’s too warm it’ll bolt—or flower—too early, meaning a shorter harvest. Make sure to keep your plants away from direct sunlight and that your indoor garden is placed somewhere that’s not too warm: below 70°F is best to ensure full optimal growth for your romaine salads.

While romaine is one of the hardier leaf greens, it still requires a moderate amount of attention and upkeep—the Gardyn Home Kit 3.0 can alleviate all the guesswork out of cultivating your own fruits and vegetables. Its hydroponic system means you can forgo soil entirely, and the Gardyn app lets you control the lights and watering system as well as monitor temperature so you know your romaine is healthy as can be.

How To Plant Romaine Indoors

You’ve purchased your romaine seeds—or maybe seedlings, if you want less guesswork—and now you have to plant them. Here’s how to set up an indoor garden tailored for romaine.

Step 1: Preparing The Planter

Romaine will grow best in wide, shallow containers with plenty of drainage holes—just make sure you have something underneath to catch the water drainage! A simple plastic window box will work great to start your indoor romaine garden.

Step 2: Planting Your Romaine

There are two options when planting romaine: planting the seeds from scratch, or buying seedlings and transplanting them. If planting seeds, sow them in the top layer of soil, tamp down, and then cover with a very light layer of soil—romaine seeds need light to germinate and sprout. If you’re transplanting romaine, the method is like any other seedling: simply dig a hole large enough for the pot it came in, place the seedling inside, and then fill the remaining space with soil.

Step 3: When To Plant

No need to wait for the last frost to be over—the good news about an indoor garden is your plants are never out of season. You control the climate, so romaine grown indoors will thrive year-round. Romaine takes 60-80 days to grow from when it is planted, and then will continue to produce for 3-5 weeks after it matures.

Gardyn makes home gardening simple. Using yCube technology, planting romaine is as simple as slotting the seedling into your Gardyn Home Kit—that’s it! The automated watering and lighting systems take care of the rest, and all you’ll have to do is harvest your plants when you’re ready to eat.

How to Care for Your Romaine

So you’ve planted your romaine—now how do you care for it? Growing romaine lettuce is one of the easier plants to grow. Learn and follow these simple tips and your garden will be flourishing in no time.

STEP 1: Watering

Romaine is one of the hardier leaf greens, but it’s susceptible to overwatering. If your romaine sits in soaked soil it’s more likely to get root rot, which will kill the plants from the bottom up. To prevent this, make sure the soil isn’t too damp before watering it. No fancy tools needed—just stick your finger about 2 inches into the soil.

If the soil sticks to your finger, it’s got enough moisture, but if it’s too dry to stick, it needs to be watered.

STEP 2: Fertilizing

Though romaine can grow with just potting soil and proper care, fertilizer can greatly improve the quality of your produce. If you’ve got a compost bin, adding compost to your garden before planting can introduce nutrients and moisture that will help your plants thrive. But if your household doesn’t generate enough food waste to make composting viable, commercial brands of fertilizer specifically engineered for indoor gardens are a good pick to use for growing romaine indoors.

STEP 3: Pest Control

While romaine grown indoors is less susceptible to most pests—you (hopefully) won’t have to worry about deer munching on your heads of lettuce if it’s being grown in your kitchen. However, it can still suffer from infestations of smaller pests like aphids. These are the most common pests on indoor romaine plants, and can be dealt with by treating your plants with neem oil, insecticidal soap, or simply by washing the aphids away.

While caring for your romaine is relatively simple, the Gardyn Home Kit offers a completely hands-off solution. No need to worry about overwatering—Gardyn’s hydroponic technology gives your plants exactly how much water they need without you having to think about it. And with Gardyn’s provided plant food, your plants will get the nutrients they normally would from fertilized soil without you having to worry about mess.

Harvesting And Using Your Romaine

Romaine can be harvested one of two ways—individual leaves can be snipped off with sharp scissors, or you can cut the whole head at the base. If you’re going for the latter, make sure to leave about an inch so the plant is able to regrow.

When you think of cooking with romaine lettuce, your first thought is probably salad—and while its crisp, mild leaves make a great base for your classic Caesar or Cobb, there’s a world of recipes romaine can be used in. Cooked into soups or stews, it adds a bit of crunch and a slight, pleasant bitterness to richer dishes. It’s also sturdy enough to be used as a replacement for pitas or tortillas if you’re looking for a gluten-free alternative for your wraps. And it responds surprisingly well to heat—cook some in a pan like any other leafy green or throw a whole wedge on the grill for a gorgeous char.

Choose the best indoor garden solution on the market

Unveil the future of indoor gardening with Gardyn’s Home Kit! Superior to competitors, our kit offers effortless gardening through innovative yCube technology, automating the growing process for busy individuals. With the ability to cultivate a diverse array of plants, Gardyn ensures an efficient, user-friendly experience, backed by robust customer support and a competitive warranty. Choose Gardyn, where technology meets convenience in creating lush, indoor green spaces.

Delicious Leafy Greens Every Time with Gardyn

Romaine is one of the best plants to grow in an indoor garden—it has countless uses in cooking and is simple to grow. The Gardyn Home Kit makes it even easier.

Gardyn offers two varieties of romaine, classic green and a vibrant red, both in Gardyn’s plug-and-play yCubes for easy, no-mess setup. Just pop the yCubes into your home kit and watch your garden thrive. Gardyn’s automated watering and lighting system will take care of the hard work of caring for your plants, and you can enjoy fresh vegetables at any time.

A Gardyn membership will unlock even more features. One membership perk is AI assistant Kelby, who utilizes Gardyn’s cameras and sensors to give you tips on how to best care for your plants as well as device alerts such as low water levels so your garden is running smoothly all the time. You’ll also save 60% on additional yCube purchases—grab some cherry tomatoes and cucumbers with your romaine and grow a whole salad right in your kitchen!

You can be sure you’re getting the best quality produce when growing it yourself, and it’ll always be fresh right when you’re ready to cook. Gardyn will revolutionize the way you eat, giving you fresher, healthier produce right in the comfort of your own home. Join us as we continue to embark on our Gardyning journey. Visit our website today.

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