How Long Does It Take to Grow Romaine Lettuce? A Detailed Guide to Growing This Delicious Leafy Green

Romaine lettuce, also known as cos lettuce, is a crunchy, sweet, and delicious leafy green that is popular in salads and sandwiches. With its long, upright leaves and sturdy midribs, romaine stands out from other lettuce varieties that form loose or round heads.

If you’ve never grown romaine lettuce before, you may be wondering – how long does it take to grow romaine lettuce from seed to harvest? In this detailed guide, we’ll cover everything you need to know, from optimal planting times to how long romaine takes to mature and how to get the biggest harvest

An Overview of Romaine Lettuce

Before we dive into timing, let’s go over some key facts about romaine lettuce:

• Botanical name Lactuca sativa var longifolia

• Plant type: Annual vegetable

• Mature size: 12-20 inches tall

• Sun exposure: Full sun to partial shade

• Soil: Loose, nutrient-rich, well-drained

• Hardiness zones: 2-11

Romaine is known for its upright growth habit, with new leaves forming around a central stalk. The leaves are elongated and cup-shaped, ranging in color from deep green to red depending on variety. It’s more heat and cold tolerant than other lettuces.

When to Plant Romaine Lettuce

Romaine lettuce thrives in cool weather, ideally around 60-70°F. In warm climates, focus on planting romaine in late summer/early fall and late winter/early spring. Avoid the hottest summer months.

In cooler regions, romaine can be grown through summer provided it gets ample water and you choose bolt-resistant varieties. For a continuous harvest, sow small batches every 2-3 weeks rather than all at once.

Spring Planting

• Start seeds indoors 6-8 weeks before your last frost date, then transplant outdoors 3-4 weeks before the last frost.

• Direct sow seeds outdoors 3-4 weeks before your last frost date.

Fall Planting

• Sow seeds 8-10 weeks before your first fall frost date for a fall harvest.

• In mild winter climates, plant in late fall/early winter for an overwintered crop.

How Long Does Romaine Lettuce Take to Mature?

From seed to harvest, romaine lettuce typically takes 60-80 days to reach full maturity. But you can begin harvesting individual leaves much sooner than that, as soon as 30-45 days after sowing.

Here’s a more detailed timeline of what to expect:

• Seeds germinate in 2-7 days when soil temperatures are 45-75°F.

• Seedlings emerge in 7-10 days. Thin seedlings to 6 inches apart.

• Harvest baby greens 3-4 weeks after sowing. Pick individual outer leaves but allow the plant to keep growing.

• Begin head formation around 6 weeks. Romaine starts forming a loose head as the plant matures.

• Harvest entire heads 60-80 days after sowing. Cut the whole head 1-2 inches above the base once fully sized.

Harvesting Romaine Lettuce

There are a couple techniques for harvesting romaine:

• Cut and come again: Remove mature outer leaves individually, leaving the center intact so the plant keeps producing new leaves.

• Cut whole heads: Slice off the entire head about 2 inches above the base once it reaches full size. This is best saved for the final fall harvest.

For the highest yields over an extended season, use the cut and come again method. Only harvest what you need each time and let the plant regrow leaves before cutting more. Harvest in the cool of the morning when leaves are crispest.

Tips for Maximizing Your Romaine Lettuce Harvest

Follow these tips to get the biggest and fastest harvest from your romaine lettuce:

• Choose fast-maturing varieties like Little Gem that mature quickly, in as little as 50 days.

• Start seeds indoors for a head start on the growing season.

• Use row covers to protect from cold temperatures if growing into winter.

• Provide ample water – at least 1 inch per week. Proper water is key.

• Apply a balanced liquid fertilizer every 2-3 weeks to fuel growth.

• Cut outer leaves frequently to promote new growth. Don’t wait until heads are massive.

• Pull spent plants after final harvest and replant for continuous yields.

Growing Romaine Lettuce in Pots

Romaine lettuce also grows well in containers. Choose a pot at least 12 inches deep with drainage holes. Allow 1-2 gallons of potting mix per plant. Place transplants or sow seeds 6-8 inches apart. Grow on a sunny patio or balcony. Provide frequent watering and fertilizer. Harvest leaves as needed once they size up.

How Long Does Romaine Lettuce Last After Harvesting?

Freshly cut romaine will last 7-10 days when properly stored in the refrigerator. Leave the leaves attached at the base and store them upright in a glass of water, loosely wrapped in plastic. Or place dry leaves in a zip-top bag with a paper towel to absorb moisture. The leaves will slowly lose their crunchy texture but can still be eaten.

For long-term storage, blanch leaves in boiling water for 15-30 seconds then shock in ice water. Dry thoroughly and freeze leaves in airtight bags for up to 8 months. Thaw before using.

Troubleshooting Common Romaine Lettuce Problems

Here are some potential issues and how to address them:

• Bolting – Plants prematurely shoot up flower stalks. This happens when temperatures get too hot. Plant bolt-resistant varieties and time plantings for optimal seasons.

• Tipburn – Brown crispy edges on leaves caused by inconsistent water. Keep soil consistently moist. Provide mulch and shade in hot weather.

• Pests – Use floating row covers to keep pests off plants. Hand pick any bugs found. Spray insecticidal soap or neem oil if needed.

• Diseases – Improve airflow and avoid overhead watering. Remove and destroy any infected plants. Disinfect tools between uses.

Growing crunchy, sweet romaine lettuce at home is very rewarding. Time your plantings for cool weather and allow 60-80 days for full size heads to develop. But you can start harvesting individual leaves as soon as 3-4 weeks after sowing seeds. Use the cut and come again method for an ongoing harvest over weeks or months. With proper care, any gardener can enjoy fresh romaine lettuce straight from their backyard.