Harman US

Frost Dates for Dennis, MS

Last spring frost
Apr 9
First fall frost
Oct 28
Growing season
203 days
Hardiness zone
8a

In an average year around Dennis, MS, the last spring frost (32°F) is about Apr 9 and the first fall frost is about Oct 28, giving roughly a 203-day growing season. To be safe most years, wait until Mar 23 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 - Dennis, MS
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 3 Apr 20 Apr 7
Freeze (32°F) Apr 24 Apr 9 Mar 23
Hard (28°F) Apr 13 Mar 29 Mar 11
Severe (24°F) Apr 2 Mar 16 Feb 24
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 3 Apr 29 Apr 26 Apr 23 Apr 20 Apr 18 Apr 15 Apr 12 Apr 7
32°F Apr 24 Apr 19 Apr 15 Apr 12 Apr 9 Apr 6 Apr 2 Mar 30 Mar 23
28°F Apr 13 Apr 7 Apr 4 Apr 1 Mar 29 Mar 26 Mar 22 Mar 17 Mar 11
24°F Apr 2 Mar 28 Mar 23 Mar 19 Mar 16 Mar 12 Mar 7 Mar 1 Feb 24
20°F Mar 20 Mar 15 Mar 9 Mar 4 Mar 1 Feb 25 Feb 19 Feb 14 Feb 5
16°F Mar 10 Mar 1 Feb 25 Feb 18 Feb 12 Feb 6 Feb 1 Jan 25 Jan 15

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 - Dennis, MS
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Oct 7 Oct 18 Oct 31
Freeze (32°F) Oct 15 Oct 28 Nov 9
Hard (28°F) Oct 24 Nov 5 Nov 22
Severe (24°F) Nov 1 Nov 16 Dec 4
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Oct 7 Oct 11 Oct 14 Oct 16 Oct 18 Oct 21 Oct 24 Oct 27 Oct 31
32°F Oct 15 Oct 20 Oct 23 Oct 26 Oct 28 Oct 31 Nov 2 Nov 5 Nov 9
28°F Oct 24 Oct 29 Nov 1 Nov 3 Nov 5 Nov 8 Nov 12 Nov 16 Nov 22
24°F Nov 1 Nov 6 Nov 10 Nov 14 Nov 16 Nov 20 Nov 24 Nov 30 Dec 4
20°F Nov 10 Nov 16 Nov 21 Nov 26 Dec 1 Dec 3 Dec 9 Dec 16 Dec 27
16°F Nov 20 Dec 1 Dec 6 Dec 13 Dec 22 Dec 28 Jan 2 Jan 7 Jan 17

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: Iuka, Ms, about 15.4 miles away@if(!empty($station['elevation_ft'])), at 600 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

@endif
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 Dennis, MS?

On average, the last spring frost (32°F) around Dennis, MS is about Apr 9. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 23.

When is the first frost in the fall?

The first fall frost around Dennis, MS typically arrives about Oct 28. 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 9 on average, or Mar 23 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 203 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 38838 Planting calendar → Mississippi frost dates →

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