Lettuce is planted three to four weeks before your last spring frost and sown again in late summer for fall. It grows best in cool weather and bolts in summer heat. Find your zone below, or enter your ZIP code for dates based on the weather station closest to you.
Lettuce dates for your ZIP code
Planting times based on university extension guidance (UNH, Cornell, Purdue, Minnesota, Nebraska and UMass Extension). Frost dates from NOAA 1991–2020 U.S. Climate Normals, nearest weather station. Zones derived from the 2023 USDA Plant Hardiness Zone Map data (PRISM Climate Group, Oregon State University). This is not the official USDA Plant Hardiness Zone Map.
Lettuce planting dates by zone
| USDA zone | When to plant |
|---|---|
| Zone 3 | April 25 – May 2 |
| Zone 4 | April 18 – April 25 |
| Zone 5 | April 10 – April 17 |
| Zone 6 | April 3 – April 10 |
| Zone 7 | March 20 – March 27 |
| Zone 8 | March 3 – March 10 |
| Zone 9 | February 3 – February 10 |
Not sure of your zone? Look it up by ZIP code.
Why lettuce is planted before the last frost
Lettuce is a cool-season, semi-hardy crop. It tolerates light frost and grows best in mild weather, so it goes into the garden weeks before the last spring frost. Heat and long summer days make it bolt: the plant sends up a flower stalk and the leaves turn bitter. That is why lettuce is grown in spring and again in fall.
How to plant lettuce
- Sow seeds ¼ inch deep directly in the garden, or start transplants indoors four to five weeks ahead.
- Thin leaf lettuce to 4–8 inches apart when seedlings are 1–2 inches tall. You can eat the thinnings.
- Space heading types wider: butterhead and romaine 6–10 inches apart, crisphead 12–15 inches.
- Water lightly and often to keep growth fast and tender.
- Sow small batches every couple of weeks for a steady harvest.
Harvesting lettuce
Pick leaf lettuce when plants are 5–6 inches tall, starting with the outer leaves, or cut whole plants an inch above the soil: they often regrow for a second cut in two to three weeks. Harvest butterhead when the leaves cup inward, romaine when it forms a head 6–8 inches tall, and crisphead when the head feels firm. Store lettuce dry and unwashed in a bag in the refrigerator.
Frequently asked questions
Can I plant lettuce before the last frost?
Yes. Lettuce tolerates light frost and grows best in cool weather, so it is planted three to four weeks before your last spring frost.
How often should I sow lettuce?
Sow a short row every couple of weeks. That gives you a steady supply instead of more lettuce than you can eat at once.
Why is my lettuce bitter?
Heat and long days make lettuce bolt and turn bitter. Harvest before hot weather, and choose slow-bolting varieties for late spring.
Sources. Planting dates use the median frost dates of each USDA zone, calculated from NOAA climate data for every ZIP code in the zone.