Frost dates by ZIP code
Your frost dates are the median last spring and first fall 32 F nights at the NOAA weather station nearest your ZIP code, from the 1991-2020 Climate Normals. Enter a ZIP for your dates, then pick a crop for its seed-starting and planting dates.
Source: NOAA NCEI 1991-2020 U.S. Climate Normals. ZIP locations: U.S. Census Bureau 2025 Gazetteer (ZCTA).
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Frost cloth for a frost night
Three covers, from light frost to a hard freeze. How we chose them: our frost cloth and row cover buying guide.
Our top picks
Our pick for light frost and fall greens
1. Agribon AG-19 Floating Row Cover
Best for: Light frost on greens, most light
Our pick for colder nights and overwintering
2. Agribon AG-30 Row Cover
Best for: Repeated frosts, a moderate winter
Our pick for a hard freeze down to 24 F
3. Gardener's Supply GardenQuilt Row Cover
Best for: Nights down to 24 F, cover all winter
Frost date questions
What is a last frost date?
Your last frost date is the day by which the last 32 F night of spring has passed in half of years. NOAA calls it the 50 percent probability date in its 1991-2020 Climate Normals. In the other half of years a frost comes later, so frost-tender crops wait until at least this date.
Where do these frost dates come from?
These dates come from NOAA's 1991-2020 U.S. Climate Normals at the weather station nearest your ZIP code. Each result names the station and its distance from the center of your ZIP. ZIP locations come from the U.S. Census Bureau 2025 Gazetteer. In mountains or near a coast, the station can sit at another elevation than your garden.
Why does another site show a different frost date?
Sites differ in threshold and station: the Old Farmer's Almanac prints 30 percent dates, later in spring and earlier in fall than the NOAA median at the same station. In our check of 20 ZIP codes the gap was 3 to 9 days; across all NOAA stations we use, 3 to 29 days in spring, 3 to 21 in fall.
How sure is my frost date?
Your frost date is a median, so in about half of years the last spring frost comes later. Each result also shows the 1 in 10 dates from the same NOAA 1991-2020 normals: in spring, a 32 F night comes after that date in only 1 year in 10. Plan frost-tender crops around both dates.
How are the seed-starting dates worked out?
Each crop's dates count weeks before or after your frost dates, using rules published by university extension services, mostly Montana State University Extension's MontGuide MT199308AG. The sources are linked under every result. Frost-tender crops such as tomatoes, peppers and squash are never scheduled outdoors before your median last frost date.