Last spring frost
Apr 12
Frost Dates for Mammoth Spring, AR
First fall frost
Oct 24
Growing season
194 days
Hardiness zone
7a
In an average year around Mammoth Spring, AR, the last spring frost (32°F) is about Apr 12 and the first fall frost is about Oct 24, giving roughly a 194-day growing season. To be safe most years, wait until Mar 27 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 6 | Apr 24 | Apr 9 |
| Freeze (32°F) | Apr 27 | Apr 12 | Mar 27 |
| Hard (28°F) | Apr 16 | Apr 1 | Mar 13 |
| Severe (24°F) | Apr 5 | Mar 18 | Feb 28 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 6 | May 2 | Apr 30 | Apr 27 | Apr 24 | Apr 21 | Apr 17 | Apr 13 | Apr 9 |
| 32°F | Apr 27 | Apr 23 | Apr 19 | Apr 15 | Apr 12 | Apr 9 | Apr 6 | Apr 1 | Mar 27 |
| 28°F | Apr 16 | Apr 11 | Apr 8 | Apr 4 | Apr 1 | Mar 29 | Mar 25 | Mar 19 | Mar 13 |
| 24°F | Apr 5 | Mar 31 | Mar 27 | Mar 22 | Mar 18 | Mar 14 | Mar 10 | Mar 5 | Feb 28 |
| 20°F | Mar 25 | Mar 18 | Mar 14 | Mar 10 | Mar 6 | Mar 2 | Feb 28 | Feb 24 | Feb 16 |
| 16°F | Mar 15 | Mar 8 | Mar 4 | Feb 28 | Feb 25 | Feb 20 | Feb 15 | 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 3 | Oct 16 | Oct 26 |
| Freeze (32°F) | Oct 11 | Oct 24 | Nov 5 |
| Hard (28°F) | Oct 21 | Nov 3 | Nov 20 |
| Severe (24°F) | Oct 31 | Nov 13 | Dec 2 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 3 | Oct 7 | Oct 10 | Oct 13 | Oct 16 | Oct 18 | Oct 20 | Oct 23 | Oct 26 |
| 32°F | Oct 11 | Oct 17 | Oct 20 | Oct 22 | Oct 24 | Oct 26 | Oct 30 | Nov 1 | Nov 5 |
| 28°F | Oct 21 | Oct 25 | Oct 29 | Nov 1 | Nov 3 | Nov 5 | Nov 8 | Nov 13 | Nov 20 |
| 24°F | Oct 31 | Nov 3 | Nov 6 | Nov 9 | Nov 13 | Nov 17 | Nov 21 | Nov 26 | Dec 2 |
| 20°F | Nov 7 | Nov 12 | Nov 17 | Nov 21 | Nov 25 | Nov 30 | Dec 3 | Dec 8 | Dec 15 |
| 16°F | Nov 15 | Nov 24 | Nov 29 | Dec 3 | Dec 8 | Dec 13 | Dec 18 | Dec 23 | Jan 1 |
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: Mammoth Spring, Ar, about 3.7 miles away@if(!empty($station['elevation_ft'])), at 502 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 Mammoth Spring, AR?
On average, the last spring frost (32°F) around Mammoth Spring, AR is about Apr 12. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 27.
When is the first frost in the fall?
The first fall frost around Mammoth Spring, AR 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 12 on average, or Mar 27 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 194 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 72554 Planting calendar → Arkansas frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026