Harman US

Frost Dates for Allamuchy, NJ

Last spring frost
Apr 25
First fall frost
Oct 19
Growing season
175 days
Hardiness zone
6b

In an average year around Allamuchy, NJ, the last spring frost (32°F) is about Apr 25 and the first fall frost is about Oct 19, giving roughly a 175-day growing season. To be safe most years, wait until Apr 12 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 - Allamuchy, NJ
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 22 May 7 Apr 22
Freeze (32°F) May 11 Apr 25 Apr 12
Hard (28°F) Apr 28 Apr 11 Mar 31
Severe (24°F) Apr 12 Mar 31 Mar 16
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 22 May 18 May 14 May 11 May 7 May 3 Apr 30 Apr 27 Apr 22
32°F May 11 May 6 May 2 Apr 29 Apr 25 Apr 22 Apr 20 Apr 16 Apr 12
28°F Apr 28 Apr 21 Apr 17 Apr 15 Apr 11 Apr 8 Apr 5 Apr 3 Mar 31
24°F Apr 12 Apr 6 Apr 3 Apr 1 Mar 31 Mar 28 Mar 24 Mar 20 Mar 16
20°F Apr 1 Mar 29 Mar 25 Mar 22 Mar 19 Mar 17 Mar 14 Mar 10 Mar 4
16°F Mar 23 Mar 19 Mar 16 Mar 12 Mar 10 Mar 7 Mar 4 Feb 28 Feb 22

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 - Allamuchy, NJ
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 26 Oct 6 Oct 22
Freeze (32°F) Oct 5 Oct 19 Nov 3
Hard (28°F) Oct 15 Oct 31 Nov 13
Severe (24°F) Oct 27 Nov 12 Nov 29
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 26 Sep 30 Oct 2 Oct 4 Oct 6 Oct 9 Oct 12 Oct 16 Oct 22
32°F Oct 5 Oct 9 Oct 13 Oct 16 Oct 19 Oct 22 Oct 25 Oct 30 Nov 3
28°F Oct 15 Oct 20 Oct 25 Oct 28 Oct 31 Nov 2 Nov 5 Nov 9 Nov 13
24°F Oct 27 Nov 1 Nov 5 Nov 9 Nov 12 Nov 15 Nov 18 Nov 22 Nov 29
20°F Nov 10 Nov 14 Nov 19 Nov 22 Nov 26 Nov 29 Dec 2 Dec 6 Dec 13
16°F Nov 21 Nov 27 Dec 1 Dec 4 Dec 7 Dec 11 Dec 16 Dec 21 Dec 27

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: Andover Aeroflex Ap, Nj, about 6.4 miles away@if(!empty($station['elevation_ft'])), at 583 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 Allamuchy, NJ?

On average, the last spring frost (32°F) around Allamuchy, NJ is about Apr 25. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 12.

When is the first frost in the fall?

The first fall frost around Allamuchy, NJ typically arrives about Oct 19. 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 25 on average, or Apr 12 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 175 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 07820 Planting calendar → New Jersey frost dates →

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