Last spring frost
Apr 5
Frost Dates for New Haven, IL
First fall frost
Oct 31
Growing season
209 days
Hardiness zone
7a
In an average year around New Haven, IL, the last spring frost (32°F) is about Apr 5 and the first fall frost is about Oct 31, giving roughly a 209-day growing season. To be safe most years, wait until Mar 21 before setting out tender plants.
Last spring frost
Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | May 5 | Apr 15 | Apr 2 |
| Freeze (32°F) | Apr 21 | Apr 5 | Mar 21 |
| Hard (28°F) | Apr 9 | Mar 24 | Mar 6 |
| Severe (24°F) | Mar 30 | Mar 13 | Feb 24 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 5 | Apr 28 | Apr 23 | Apr 19 | Apr 15 | Apr 13 | Apr 9 | Apr 6 | Apr 2 |
| 32°F | Apr 21 | Apr 14 | Apr 11 | Apr 8 | Apr 5 | Apr 2 | Mar 31 | Mar 26 | Mar 21 |
| 28°F | Apr 9 | Apr 3 | Mar 31 | Mar 28 | Mar 24 | Mar 21 | Mar 17 | Mar 12 | Mar 6 |
| 24°F | Mar 30 | Mar 24 | Mar 20 | Mar 17 | Mar 13 | Mar 8 | Mar 5 | Mar 1 | Feb 24 |
| 20°F | Mar 19 | Mar 14 | Mar 8 | Mar 5 | Mar 2 | Feb 28 | Feb 23 | Feb 17 | Feb 9 |
| 16°F | Mar 12 | Mar 5 | Mar 1 | Feb 24 | Feb 20 | Feb 15 | Feb 10 | Feb 4 | Jan 27 |
First fall frost
Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Oct 8 | Oct 21 | Nov 1 |
| Freeze (32°F) | Oct 19 | Oct 31 | Nov 11 |
| Hard (28°F) | Oct 30 | Nov 8 | Nov 26 |
| Severe (24°F) | Nov 4 | Nov 18 | Dec 7 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 8 | Oct 13 | Oct 17 | Oct 19 | Oct 21 | Oct 24 | Oct 26 | Oct 29 | Nov 1 |
| 32°F | Oct 19 | Oct 23 | Oct 26 | Oct 29 | Oct 31 | Nov 1 | Nov 4 | Nov 7 | Nov 11 |
| 28°F | Oct 30 | Nov 1 | Nov 3 | Nov 5 | Nov 8 | Nov 10 | Nov 14 | Nov 18 | Nov 26 |
| 24°F | Nov 4 | Nov 8 | Nov 11 | Nov 14 | Nov 18 | Nov 22 | Nov 27 | Dec 1 | Dec 7 |
| 20°F | Nov 12 | Nov 17 | Nov 22 | Nov 27 | Dec 1 | Dec 4 | Dec 8 | Dec 15 | Dec 22 |
| 16°F | Nov 22 | Nov 30 | Dec 4 | Dec 9 | Dec 15 | Dec 20 | Dec 24 | Dec 30 | Jan 7 |
Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.
Where this data comes from
@endif These dates are computed from the nearest official weather station with long-term records: Jt Myers Locks & Dam, In, about 9.9 miles away@if(!empty($station['elevation_ft'])), at 340 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
How we calculate these dates
Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.
Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.
Frequently asked questions
When is the last frost in New Haven, IL?
On average, the last spring frost (32°F) around New Haven, IL is about Apr 5. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 21.
When is the first frost in the fall?
The first fall frost around New Haven, IL typically arrives about Oct 31. Count back by a crop's days to maturity to find the latest date you can plant it.
When can I plant tomatoes and other tender crops?
Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 5 on average, or Mar 21 to be safe most years.
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 209 days in a typical year.
Are these dates a forecast for this year?
No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.
Local weather for 62867 Planting calendar → Illinois frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026