Today, I am excited to take you through a step-by-step guide on how to grow romaine lettuce from seed. It’s actually one of my favorite vegetables!
Growing your own romaine lettuce is not only rewarding but also delicious!
Whether you have a full backyard garden filled with vegetables or just a few pots on a balcony, romaine lettuce thrives with just a little care.
In this guide, you’ll learn how to grow romaine lettuce from seed—including the history of this rich green leafy vegetable, what tools you’ll need, expert tips, and frequently asked questions.
Related: 10 Best Companion Plants for Lettuce
📜 The History of Romaine Lettuce
Romaine lettuce, also known as cos lettuce, boasts an impressive history stretching back over 5,000 years.
Ancient Egyptian artwork depicts workers harvesting heads of lettuce, indicating that it was a valued crop even back then.
The name “romaine” comes from its popularity in Rome, where it was cultivated extensively and celebrated for its crisp texture and refreshing taste.
Over centuries, romaine lettuce spread throughout Europe and eventually the world, becoming a beloved staple in dishes like Caesar salads and Mediterranean wraps.
Fun Fact:
- In Ancient Egypt, lettuce was considered a symbol of fertility and health.
- The word “cos” comes from the Greek island of Kos, where the variety was once widely grown.
🥬 Different Types of Lettuce You Should Know
While this guide focuses on how to grow romaine lettuce from seed, it’s fun to explore the five major types of lettuce commonly grown in home gardens:
🌿 1. Romaine (Cos Lettuce)
- Tall, elongated heads.
- Crisp texture with sweet, mild flavor.
- Heat-tolerant compared to other types.
🥗 2. Butterhead (e.g., Boston and Bibb)
- Soft, buttery leaves.
- Loose heads.
- Mild, delicate flavor — great for wraps.
🥬 3. Crisphead (e.g., Iceberg)
- Tight, crunchy heads.
- Mild flavor.
- Prefers cooler growing conditions.
🌱 4. Loose-Leaf
- No head formation — leaves grow loosely.
- Fast-growing and super easy for beginners.
- Variety of colors: green, red, bronze.
🥬 5. Batavia (Summer Crisp)
- Cross between crisphead and loose-leaf.
- Crisp but tender.
- Tolerates heat better than other types.
📋 Quick Comparison Table
| Type of Lettuce | Texture | Flavor | Growth Style |
| Romaine | Crisp | Mild-sweet | Upright head |
| Butterhead | Soft | Mild | Loose head |
| Crisphead | Crunchy | Mild | Tight head |
| Loose-leaf | Tender | Mild to slightly bitter | No head |
| Batavia | Crisp & tender | Sweet | Loose to semi-tight head |
🧰 Tools and Equipment Needed to Grow Romaine Lettuce
Before you plant your first seed, gather these essentials:
| Tools/Equipment | Purpose |
| Seeds | Choose high-quality romaine lettuce seeds. |
| Seed Tray or Small Pots | For indoor germination. |
| Potting Mix | Use a light, well-draining mix. |
| Watering Can with Fine Spout | Gentle watering without disturbing seeds. |
| Grow Lights (Optional) | Helpful if starting seeds indoors. |
| Trowel | For transplanting seedlings later. |
| Fertilizer (Organic Preferably) | Boosts healthy growth. |
| Garden Labels | To mark your plantings. |
🌱 How to Grow Romaine Lettuce from Seed
Let’s dive into the step-by-step process of growing this crunchy favorite from seed.
🏡 Step 1: Choose the Right Location
(Source: ToAgriculture.com)
Romaine lettuce needs at least 6 hours of sunlight daily. If you’re planting outdoors, pick a spot that gets morning sun and some afternoon shade (especially in hot regions).
Indoor growing? A sunny windowsill or grow light works wonders.
🥄 Step 2: Prepare the Soil
Romaine loves rich, loose, and well-draining soil. Here’s how to prep:
- Mix compost or aged manure into the soil.
- Aim for a soil pH of 6.0 to 6.8.
- Loosen the soil about 6–8 inches deep.
Pro Tip: Avoid compacted soils—roots love room to breathe!
🌱 Step 3: Plant the Seeds
(Source: Storables)
- Sow seeds 1/4 inch deep directly into the soil.
- Space seeds about 1 inch apart.
- Cover lightly with soil.
- Mist gently with water (do not drench).
Indoor Planting? Start seeds indoors 4–6 weeks before the last expected frost date, then transplant once seedlings are strong.
💧 Step 4: Watering
- Keep the soil evenly moist (not soggy).
- Water early in the day to allow leaves to dry and prevent disease.
- Consistent moisture = tender, sweet leaves!
Quick Tip: Use mulch around plants to lock in moisture.
🌿 Step 5: Thinning the Seedlings
It is important to note that the right time to thin your Romaine Lettuce seedings is when they are about 2 inches tall.
- Thin them to 6–8 inches apart.
- Choose the strongest, healthiest plants to keep.
By the way, I have noticed that my friend Audrey from Audrey’s Little Farm has a nice video on how to thin your Romaine Lettuce seedings.
Watch it below:
Pro Tip: Don’t waste the thinnings—they’re edible microgreens!
☀️ Step 6: Maintain Proper Care
- Fertilize once or twice with a balanced liquid fertilizer.
- Watch for pests like aphids or slugs.
- Provide shade cloth in extreme heat to prevent bolting.
🥗 Step 7: Harvesting Your Romaine Lettuce
(Source: Plantura.garden)
- Harvest when heads are compact and about 6–8 inches tall.
- Use a sharp knife to cut at the base.
- Alternatively, harvest outer leaves and allow the center to keep growing (“cut and come again” method).
Fun Tip: Romaine can regrow after cutting!
💡 Expert Tips for Growing Romaine Lettuce Successfully
🌟 Succession Planting: Plant seeds every 2–3 weeks for a continuous harvest.
🌟 Cool Season Magic: Lettuce prefers cooler temps—ideal growing range is 45–75°F.
🌟 Disease Prevention: Water at the base of the plants, not on the leaves.
🌟 Container Gardens: Growing in pots? Choose a 12-inch deep container minimum.
🥗 Romaine Lettuce Nutritional Facts
Photo credit: Pinterest
Romaine lettuce isn’t just crunchy and refreshing — it’s packed with essential nutrients that make it a smart addition to any diet!
Here’s a breakdown of the major nutritional highlights:
📊 Nutritional Value Per 100 Grams (about 2 cups shredded)
| Nutrient | Amount |
| Calories | 17 kcal |
| Protein | 1.2 g |
| Fat | 0.3 g |
| Carbohydrates | 3.3 g |
| Fiber | 2.1 g |
| Sugars | 1.2 g |
| Vitamin A | 148% of Daily Value (DV) |
| Vitamin K | 109% of DV |
| Folate (Vitamin B9) | 34% of DV |
| Vitamin C | 15% of DV |
| Potassium | 247 mg |
| Calcium | 33 mg |
| Iron | 1 mg |
(Source: USDA FoodData Central)
🌟 Health Benefits of Romaine Lettuce
Boosts Eye Health: Thanks to its high vitamin A content, romaine supports good vision and eye health.
Supports Bone Strength: Rich in vitamin K and calcium, romaine helps maintain strong, healthy bones.
Heart-Healthy: Its folate content helps reduce homocysteine levels, promoting better heart health.
Accoridng to MedicalNewsToday, lettuce contains high levels of potassium, which is responsible for maintaining cardiovascular health.
The same document says that Vitamins A and C antioxidants in lettuce may aid in the prevention of cholesterol build-up in the arteries.
Low-Calorie, High-Fiber: Perfect for weight management and digestive health.
✅ Expert Tip
Add romaine to your daily diet by tossing it into smoothies, wraps, or as a crunchy base for hearty salads!
❓ FAQs About How to Grow Romaine Lettuce from Seed
🥬 Q: How long does it take for romaine lettuce seeds to germinate?
A: Typically, 7–14 days, depending on temperature and soil conditions.
🌡️ Q: What’s the ideal temperature for growing romaine lettuce?
A: 55–70°F is best. Hotter temperatures can cause the lettuce to bolt and turn bitter.
🚿 Q: How often should I water romaine lettuce?
A: Water 2–3 times per week, more often in hot weather.
🌱 Q: Can I grow romaine lettuce indoors year-round?
A: Yes! With adequate lighting (preferably a grow light), you can grow it indoors any time of the year.
🍃 Q: Can I regrow romaine from a store-bought stem?
A: Absolutely! Place the stem base in water until roots form, then transfer to soil.
A Must Read: Lettuce Bolting: What it Is & How to Prevent It
📋 Final Thoughts on How to Grow Romaine Lettuce from Seed
Growing romaine lettuce from seed is easy, budget-friendly, and incredibly satisfying!
With just a few basic tools, attention to watering, and a little patience, you’ll be rewarded with fresh, crunchy greens straight from your garden (or windowsill).
Start small if you’re new—even a single pot of homegrown romaine can transform your salads and wraps!