YepPlant

When to Plant Lettuce

Enter your ZIP code to see the lettuce planting windows from the frost dates at the nearest weather station. The rules below come from university extension publications and count from the average last or first frost.

Your area

Frost dates come from the weather station nearest this ZIP code.

Risk level

How much frost risk you'll accept. Each level uses the frost dates with this chance of a frost after the last-frost date or before the first-frost date: Conservative 10%, Typical 30%, Aggressive 50%.

Planting year

The year the frost dates and windows are placed on.

Lettuce planting windows

Enter ZIP code to see the lettuce planting windows for your area.

Lettuce planting rules

Each rule counts days or weeks from the average last spring frost or first fall frost in its source. YepPlant applies the same count to the 32°F frost dates at each risk level: Conservative (10%), Typical (30%), and Aggressive (50%). A range in a rule becomes a range in the window. Where sources differ or don't give a single value, the value is YepPlant's reading of the sources, and it stays within what they say.

Lettuce planting rules, from university extension publications
RuleValueSources
Frost threshold32°F frost dates—
Transplant outdoors28 to 14 days before the last spring frostCSU, UMD-PYepPlant's reading of these sources
Start seeds indoors4 to 7 weeks before transplantingNCSU, CLEMYepPlant's reading of these sources
Bought seedlingsTransplant dates also apply to bought seedlingsNCSU
Sow outdoors28 to 14 days before the last spring frostCSU, USU, UMD-P
Days to maturity from sowing40 to 80 daysCSU, NCSU, UMD-P, PURYepPlant's reading of these sources
Frost Tender FactorNone: not added for this cropUNL
Last sowing dateFirst fall frost − days to maturity from sowing—
Fall plantingSow from 14 days before the earliest last sowing date through the latest last sowing datePUR, NCSU, UNLYepPlant's reading of these sources
Crop rotationNot available—

Not available means no rule from the sources is used for it, so no window depends on it. Rows without a source follow the rules shared by all crops, described on the methods and sources page.

Sources

University extension publications, with the date each was retrieved. The frost dates come from NOAA's 1991–2020 Climate Normals at the weather station nearest your ZIP code, and the station is found from the Census Bureau's ZIP Code Tabulation Areas.

CSU: Colorado State University Extension, GardenNotes #720: Vegetable Planting Guide
Used for: Transplant outdoors, Sow outdoors, Days to maturity from sowing. Retrieved October 10, 2026.
USU: Utah State University Extension: Suggested Vegetable Planting Dates for Utah
Used for: Sow outdoors. Retrieved October 10, 2026.
UMD-P: University of Maryland Extension: Vegetables for Spring and Fall Planting
Used for: Transplant outdoors, Sow outdoors, Days to maturity from sowing. Retrieved October 10, 2026.
NCSU: NC State Extension, Extension Gardener Handbook Chapter 16: Vegetable Gardening
Used for: Start seeds indoors, Bought seedlings, Days to maturity from sowing, Fall planting. Retrieved October 10, 2026.
CLEM: Clemson Cooperative Extension, HGIC 1259: Starting Seeds Indoors
Used for: Start seeds indoors. Retrieved October 10, 2026.
UMD-S: University of Maryland Extension HGIC: Starting Vegetable Seeds Indoors
Consulted, but no rule on this page comes from it. Retrieved October 10, 2026.
PUR: Purdue Extension, HO-66-W: The Fall Vegetable Garden
Used for: Days to maturity from sowing, Fall planting. Retrieved October 10, 2026.
UNL: Nebraska Extension, NebGuide G1343: Fall Vegetable Gardening
Used for: Frost Tender Factor, Fall planting. Retrieved October 10, 2026.
OSU: Oregon State University Extension: Plant cold-hardy vegetables now for a spring harvest
Consulted, but no rule on this page comes from it. Retrieved October 10, 2026.

Data sources

NOAA U.S. Climate Normals, frost dates, 1991–2020 normals, version 1.0.1
Files: us-climate-normals_1991-2020_v1.0.1_annualseasonal_multivariate_by-station_c20230404.tar.gz, inventory_30yr.txt from NOAA NCEI. Retrieved October 10, 2026.
U.S. Census Bureau ZIP Code Tabulation Areas, 2026 Gazetteer Files and 2020 ZCTA to County Relationship File
Files: 2026_Gaz_zcta_national.zip, tab20_zcta520_county20_natl.txt, national_state2020.txt from the U.S. Census Bureau. Retrieved October 10, 2026.