Lettuce prefers cool weather, so plant it as soon as the soil can be worked in early spring. Knowing when to plant lettuce is key to a crisp, abundant harvest. Plant too late, and your lettuce will bolt—turning bitter and shooting up a flower stalk. This guide walks you through the perfect timing for every season and growing method.
Think of lettuce as a cool-weather friend. It thrives in temperatures between 45°F and 65°F (7°C–18°C). Heat stresses it out, so your job is to work with the calendar. Let’s break it down by region and planting style.
When To Plant Lettuce By Season
Timing depends on your local climate. Lettuce can be planted in spring, fall, and even winter in mild areas. Here’s a season-by-season look.
Spring Planting
Spring is the classic time. As soon as the soil is workable—usually 2–4 weeks before the last frost date—you can sow seeds or set out transplants. Lettuce seeds can germinate in soil as cold as 40°F (4°C), though they prefer 50°F–60°F (10°C–15°C).
- Check your last frost date online.
- Count back 3–4 weeks for direct sowing.
- For transplants, set them out 2 weeks before the last frost.
- Use row covers if a late frost threatens.
If you live in a cold climate (USDA zones 3–5), aim for late March to early April. Warmer zones (6–8) can start in February or March. Southern zones (9–10) often plant in late winter.
Fall Planting
Fall lettuce is often sweeter because cooler temps reduce bitterness. Plant 6–8 weeks before your first fall frost. This gives lettuce time to mature before freezing weather hits.
- Find your first fall frost date.
- Count back 8 weeks for head lettuce, 6 weeks for leaf types.
- Sow seeds directly in late summer or early fall.
- Water consistently; fall soil can be dry.
- Use shade cloth if temperatures spike above 80°F (27°C).
In mild climates (zones 8–10), you can plant fall lettuce as late as October or November. The key is to avoid heat stress during germination.
Winter Planting
In zones 7–10, lettuce can be planted in winter for a late-winter or early-spring harvest. Use cold-hardy varieties like Winter Density or Arctic King. Plant in a cold frame or under row covers for extra protection.
Even in colder zones, you can start seeds indoors 4–6 weeks before the last frost. This gives you a head start on spring.
When To Plant Lettuce Indoors Vs Outdoors
Your method matters. Starting seeds indoors gives you control over temperature and light. Direct sowing outdoors is simpler but riskier in extreme weather.
Indoor Seed Starting
Start seeds indoors 4–6 weeks before your last frost date. Use seed-starting mix and shallow trays. Lettuce seeds need light to germinate, so press them gently into the soil surface—don’t bury them deep.
- Keep soil moist but not soggy.
- Provide 12–16 hours of bright light daily.
- Maintain temperatures around 60°F–70°F (15°C–21°C).
- Harden off seedlings for 5–7 days before transplanting.
Transplant outdoors when seedlings have 3–4 true leaves and nighttime temps stay above 40°F (4°C). Space them 6–12 inches apart, depending on variety.
Direct Sowing Outdoors
Direct sowing works best when soil is cool and moist. Sow seeds 1/4 inch deep, 1 inch apart. Thin seedlings to 6–12 inches once they have 2–3 leaves. Succession planting every 2–3 weeks ensures a continuous harvest.
- Prepare soil with compost or aged manure.
- Sow seeds in rows or blocks.
- Water gently to avoid washing seeds away.
- Thin as needed.
- Mulch around plants to keep soil cool.
For fall crops, direct sow in late summer. For spring, sow as soon as the ground is workable. In hot climates, shade the soil with a light row cover to keep it cool.
When To Plant Lettuce By Variety
Different lettuce types have slightly different timing. Leaf lettuce matures fastest, while head lettuce takes longer. Here’s a quick guide.
Leaf Lettuce
Leaf lettuce (like Black Seeded Simpson or Red Sails) is the easiest. It matures in 40–50 days. Plant it every 2–3 weeks from early spring to late summer for a steady supply. It tolerates light frost well.
Romaine And Cos Lettuce
Romaine takes 60–75 days to mature. Plant it in early spring or late summer. It needs consistent moisture and cooler temps. In hot weather, romaine can bolt quickly.
Butterhead Lettuce
Butterhead (Bibb, Boston) matures in 55–70 days. It’s tender and prefers cool weather. Plant in spring or fall. Avoid planting in midsummer heat.
Crisphead (Iceberg) Lettuce
Iceberg takes the longest—80–90 days. It’s trickier to grow because it needs a long, cool season. Plant it very early in spring or in late summer for fall harvest. Many gardeners skip iceberg for easier varieties.
When To Plant Lettuce In Different Climates
Your USDA zone determines the best planting window. Here’s a breakdown by region.
Cold Climates (Zones 3–5)
Spring: Late March to early May. Use cold frames or row covers to extend the season. Fall: Plant in late July to early August for a September harvest. Winter: Not possible outdoors without a heated greenhouse.
Moderate Climates (Zones 6–8)
Spring: February to April. Fall: August to October. Winter: Possible with protection in zones 7–8. Use cold-hardy varieties and mulch heavily.
Warm Climates (Zones 9–10)
Spring: January to March. Fall: September to November. Winter: December to February. Avoid summer planting entirely—lettuce will bolt. Use shade cloth and plant in the coolest part of your garden.
Coastal Climates
Coastal areas (like the Pacific Northwest) have mild summers and cool winters. You can plant lettuce almost year-round. Spring: March to May. Fall: August to October. Winter: November to February with protection.
When To Plant Lettuce For Succession Harvesting
Succession planting keeps your salad bowl full. Instead of planting all at once, sow small batches every 2–3 weeks. This works for both spring and fall.
- Start with early spring sowings (March–April).
- Continue every 2 weeks through late spring.
- Take a break during peak summer heat.
- Resume in late summer (August) for fall harvest.
- Stop 4–6 weeks before your first frost.
This method gives you fresh lettuce for months. Just watch the weather—if a heat wave hits, your lettuce might bolt. Have shade cloth ready.
Common Mistakes When Deciding When To Plant Lettuce
Even experienced gardeners make timing errors. Here are the most common ones.
- Planting too late in spring. Lettuce hates heat. If you wait until May in a warm zone, it will bolt.
- Planting too early in fall. Hot soil prevents germination. Wait until soil cools below 80°F (27°C).
- Ignoring microclimates. A south-facing slope warms faster than a north-facing one. Adjust your timing.
- Overcrowding. Thin seedlings early to avoid competition and disease.
- Not using row covers. A late frost can kill young plants. Keep covers handy.
Another mistake is forgetting that lettuce needs consistent moisture. Dry soil stresses plants and speeds up bolting. Water deeply and regularly, especially in warm weather.
Tools To Help You Determine When To Plant Lettuce
Use these tools to nail your timing every time.
- Last frost date calculator (online or from your extension office).
- Soil thermometer—check that soil is at least 40°F (4°C).
- Weather forecast—avoid planting before a heavy rain or frost.
- Garden journal—note your planting dates and results each year.
Many gardeners also use a moon phase calendar, though science doesn’t back it. Stick to soil temperature and frost dates for reliability.
Frequently Asked Questions About When To Plant Lettuce
Here are answers to common questions. Some use variations of the keyword.
What is the best month to plant lettuce?
The best month depends on your climate. In most zones, March–April for spring and August–September for fall. In warm zones, January–February and October–November work better.
Can I plant lettuce in summer?
It’s risky. Lettuce bolts in heat above 80°F (27°C). If you try, use heat-tolerant varieties like Jericho or Summer Crisp, and provide shade. Succession planting in partial shade can work in mild summers.
How late can I plant lettuce in fall?
Plant 6–8 weeks before your first fall frost. For a late harvest, use cold-hardy types like Winter Density. You can also plant in a cold frame for extra weeks.
Should I plant lettuce seeds or transplants?
Both work. Seeds are cheaper and offer more variety. Transplants give you a head start. For fall planting, seeds are often easier because soil is warm.
Does lettuce need full sun?
Lettuce prefers full sun in cool weather but partial shade in warm conditions. In spring, give it 6–8 hours of sun. In fall, afternoon shade helps prevent bolting.
Final Tips For Perfect Timing
Timing is everything with lettuce. Start small, keep notes, and adjust each year. If you plant too early, use row covers. If you plant too late, choose heat-tolerant varieties or wait for fall.
Remember that soil temperature matters more than air temperature. A soil thermometer costs little and saves crops. Also, don’t forget to water—lettuce is mostly water and needs consistent moisture.
With the right timing, you can enjoy fresh lettuce from early spring through late fall. Even winter harvests are possible in mild climates. So grab your seeds, check your frost dates, and get planting.
One last thing: lettuce is forgiving. Even if you miss the perfect window, you can often squeeze in a late planting. Just watch the weather and be ready to protect your plants. Happy growing—and happy salads.