Last spring frost
Apr 10
Frost Dates for Pennington, NJ
First fall frost
Nov 1
Growing season
202 days
Hardiness zone
7a
In an average year around Pennington, NJ, the last spring frost (32°F) is about Apr 10 and the first fall frost is about Nov 1, giving roughly a 202-day growing season. To be safe most years, wait until Mar 30 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 11 | Apr 25 | Apr 10 |
| Freeze (32°F) | Apr 25 | Apr 10 | Mar 30 |
| Hard (28°F) | Apr 12 | Mar 31 | Mar 16 |
| Severe (24°F) | Apr 1 | Mar 18 | Feb 28 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 11 | May 6 | May 1 | Apr 28 | Apr 25 | Apr 22 | Apr 19 | Apr 15 | Apr 10 |
| 32°F | Apr 25 | Apr 20 | Apr 16 | Apr 13 | Apr 10 | Apr 8 | Apr 5 | Apr 3 | Mar 30 |
| 28°F | Apr 12 | Apr 7 | Apr 4 | Apr 2 | Mar 31 | Mar 28 | Mar 25 | Mar 21 | Mar 16 |
| 24°F | Apr 1 | Mar 28 | Mar 24 | Mar 21 | Mar 18 | Mar 14 | Mar 10 | Mar 6 | Feb 28 |
| 20°F | Mar 23 | Mar 18 | Mar 14 | Mar 10 | Mar 7 | Mar 4 | Feb 28 | Feb 24 | Feb 15 |
| 16°F | Mar 13 | Mar 8 | Mar 3 | Feb 28 | Feb 24 | Feb 18 | Feb 12 | Feb 7 | Jan 31 |
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 6 | Oct 20 | Nov 2 |
| Freeze (32°F) | Oct 15 | Nov 1 | Nov 13 |
| Hard (28°F) | Oct 29 | Nov 12 | Nov 29 |
| Severe (24°F) | Nov 9 | Nov 24 | Dec 11 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 6 | Oct 10 | Oct 14 | Oct 17 | Oct 20 | Oct 23 | Oct 26 | Oct 30 | Nov 2 |
| 32°F | Oct 15 | Oct 21 | Oct 25 | Oct 29 | Nov 1 | Nov 3 | Nov 5 | Nov 8 | Nov 13 |
| 28°F | Oct 29 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 14 | Nov 18 | Nov 22 | Nov 29 |
| 24°F | Nov 9 | Nov 13 | Nov 16 | Nov 20 | Nov 24 | Nov 28 | Dec 1 | Dec 5 | Dec 11 |
| 20°F | Nov 17 | Nov 25 | Nov 30 | Dec 3 | Dec 7 | Dec 11 | Dec 16 | Dec 22 | Dec 30 |
| 16°F | Dec 2 | Dec 9 | Dec 15 | Dec 21 | Dec 25 | Dec 31 | Jan 4 | Jan 9 | Jan 16 |
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: Trenton Mercer Co Ap, Nj, about 3.8 miles away@if(!empty($station['elevation_ft'])), at 184 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 Pennington, NJ?
On average, the last spring frost (32°F) around Pennington, NJ is about Apr 10. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 30.
When is the first frost in the fall?
The first fall frost around Pennington, NJ typically arrives about Nov 1. 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 10 on average, or Mar 30 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 202 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 08534 Planting calendar → New Jersey frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026