Last spring frost
Mar 3
Frost Dates for Port Royal, SC
First fall frost
Dec 9
Growing season
282 days
Hardiness zone
9a
In an average year around Port Royal, SC, the last spring frost (32°F) is about Mar 3 and the first fall frost is about Dec 9, giving roughly a 282-day growing season. To be safe most years, wait until Feb 2 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) | Apr 1 | Mar 16 | Feb 27 |
| Freeze (32°F) | Mar 20 | Mar 3 | Feb 2 |
| Hard (28°F) | Mar 11 | Feb 9 | Jan 9 |
| Severe (24°F) | Feb 26 | Jan 26 | Dec 29 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 1 | Mar 27 | Mar 22 | Mar 19 | Mar 16 | Mar 12 | Mar 9 | Mar 4 | Feb 27 |
| 32°F | Mar 20 | Mar 14 | Mar 9 | Mar 6 | Mar 3 | Feb 28 | Feb 22 | Feb 13 | Feb 2 |
| 28°F | Mar 11 | Mar 3 | Feb 26 | Feb 17 | Feb 9 | Feb 4 | Jan 30 | Jan 23 | Jan 9 |
| 24°F | Feb 26 | Feb 13 | Feb 4 | Jan 31 | Jan 26 | Jan 19 | Jan 12 | Jan 5 | Dec 29 |
| 20°F | Feb 12 | Feb 2 | Jan 29 | Jan 22 | Jan 17 | Jan 12 | Jan 6 | Jan 1 | Dec 24 |
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) | Nov 10 | Nov 26 | Dec 15 |
| Freeze (32°F) | Nov 21 | Dec 9 | Jan 4 |
| Hard (28°F) | Dec 3 | Dec 28 | Jan 21 |
| Severe (24°F) | Dec 13 | Jan 7 | Feb 6 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Nov 10 | Nov 15 | Nov 18 | Nov 22 | Nov 26 | Nov 30 | Dec 4 | Dec 7 | Dec 15 |
| 32°F | Nov 21 | Nov 28 | Dec 1 | Dec 5 | Dec 9 | Dec 14 | Dec 20 | Dec 27 | Jan 4 |
| 28°F | Dec 3 | Dec 9 | Dec 15 | Dec 23 | Dec 28 | Jan 1 | Jan 5 | Jan 12 | Jan 21 |
| 24°F | Dec 13 | Dec 24 | Dec 30 | Jan 2 | Jan 7 | Jan 12 | Jan 18 | Jan 26 | Feb 6 |
| 20°F | Dec 18 | Dec 29 | Jan 3 | Jan 7 | Jan 12 | Jan 18 | Jan 22 | Jan 30 | Feb 8 |
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: Beaufort Wwtp, Sc, about 0.9 miles away@if(!empty($station['elevation_ft'])), at 25 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 Port Royal, SC?
On average, the last spring frost (32°F) around Port Royal, SC is about Mar 3. In cooler years it can run later, so for a safer bet many gardeners wait until Feb 2.
When is the first frost in the fall?
The first fall frost around Port Royal, SC typically arrives about Dec 9. 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 Mar 3 on average, or Feb 2 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 282 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 29935 Planting calendar → South Carolina frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026