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Frost Dates for Caldwell, NJ

Last spring frost
Apr 18
First fall frost
Oct 24
Growing season
187 days
Hardiness zone
7a

In an average year around Caldwell, NJ, the last spring frost (32°F) is about Apr 18 and the first fall frost is about Oct 24, giving roughly a 187-day growing season. To be safe most years, wait until Apr 3 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.

Last spring frost - Caldwell, NJ
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 18 May 1 Apr 17
Freeze (32°F) May 7 Apr 18 Apr 3
Hard (28°F) Apr 19 Apr 3 Mar 22
Severe (24°F) Apr 5 Mar 24 Mar 9
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 18 May 12 May 8 May 4 May 1 Apr 29 Apr 25 Apr 22 Apr 17
32°F May 7 Apr 30 Apr 25 Apr 21 Apr 18 Apr 14 Apr 10 Apr 7 Apr 3
28°F Apr 19 Apr 12 Apr 8 Apr 5 Apr 3 Apr 1 Mar 31 Mar 27 Mar 22
24°F Apr 5 Apr 1 Mar 30 Mar 27 Mar 24 Mar 20 Mar 17 Mar 14 Mar 9
20°F Mar 28 Mar 23 Mar 18 Mar 15 Mar 13 Mar 10 Mar 7 Mar 3 Feb 27
16°F Mar 19 Mar 13 Mar 10 Mar 7 Mar 4 Mar 1 Feb 26 Feb 20 Feb 12

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.

First fall frost - Caldwell, NJ
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 30 Oct 11 Oct 26
Freeze (32°F) Oct 8 Oct 24 Nov 6
Hard (28°F) Oct 21 Nov 4 Nov 20
Severe (24°F) Nov 1 Nov 18 Dec 6
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 30 Oct 3 Oct 5 Oct 8 Oct 11 Oct 14 Oct 17 Oct 21 Oct 26
32°F Oct 8 Oct 14 Oct 17 Oct 21 Oct 24 Oct 27 Oct 30 Nov 2 Nov 6
28°F Oct 21 Oct 27 Oct 30 Nov 1 Nov 4 Nov 7 Nov 11 Nov 14 Nov 20
24°F Nov 1 Nov 6 Nov 11 Nov 14 Nov 18 Nov 22 Nov 26 Dec 1 Dec 6
20°F Nov 15 Nov 20 Nov 26 Nov 30 Dec 3 Dec 6 Dec 12 Dec 18 Dec 25
16°F Nov 29 Dec 3 Dec 10 Dec 14 Dec 19 Dec 23 Dec 28 Jan 2 Jan 9

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

These dates are computed from the nearest official weather station with long-term records: Essex Fells Service Bldg, Nj, about 1.4 miles away@if(!empty($station['elevation_ft'])), at 350 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

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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 Caldwell, NJ?

On average, the last spring frost (32°F) around Caldwell, NJ is about Apr 18. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 3.

When is the first frost in the fall?

The first fall frost around Caldwell, NJ typically arrives about Oct 24. 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 18 on average, or Apr 3 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 187 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 07006 Planting calendar → New Jersey frost dates →

Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026