Last spring frost
Mar 31
Frost Dates for Tulsa, OK
First fall frost
Nov 4
Growing season
220 days
Hardiness zone
7b
In an average year around Tulsa, OK, the last spring frost (32°F) is about Mar 31 and the first fall frost is about Nov 4, giving roughly a 220-day growing season. To be safe most years, wait until Mar 11 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 27 | Apr 10 | Mar 26 |
| Freeze (32°F) | Apr 15 | Mar 31 | Mar 11 |
| Hard (28°F) | Apr 5 | Mar 17 | Feb 28 |
| Severe (24°F) | Mar 23 | Mar 5 | Feb 17 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 27 | Apr 21 | Apr 18 | Apr 14 | Apr 10 | Apr 7 | Apr 4 | Mar 31 | Mar 26 |
| 32°F | Apr 15 | Apr 9 | Apr 5 | Apr 2 | Mar 31 | Mar 27 | Mar 23 | Mar 18 | Mar 11 |
| 28°F | Apr 5 | Mar 31 | Mar 26 | Mar 22 | Mar 17 | Mar 13 | Mar 9 | Mar 4 | Feb 28 |
| 24°F | Mar 23 | Mar 16 | Mar 12 | Mar 9 | Mar 5 | Mar 1 | Feb 27 | Feb 23 | Feb 17 |
| 20°F | Mar 12 | Mar 7 | Mar 3 | Feb 28 | Feb 25 | Feb 20 | Feb 16 | Feb 11 | Jan 31 |
| 16°F | Mar 6 | Feb 28 | Feb 23 | Feb 17 | Feb 12 | Feb 5 | Jan 31 | Jan 26 | Jan 16 |
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 11 | Oct 26 | Nov 6 |
| Freeze (32°F) | Oct 20 | Nov 4 | Nov 19 |
| Hard (28°F) | Oct 31 | Nov 13 | Dec 1 |
| Severe (24°F) | Nov 6 | Nov 25 | Dec 12 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 11 | Oct 17 | Oct 21 | Oct 23 | Oct 26 | Oct 29 | Oct 31 | Nov 3 | Nov 6 |
| 32°F | Oct 20 | Oct 26 | Oct 30 | Nov 1 | Nov 4 | Nov 6 | Nov 9 | Nov 12 | Nov 19 |
| 28°F | Oct 31 | Nov 3 | Nov 6 | Nov 10 | Nov 13 | Nov 16 | Nov 21 | Nov 25 | Dec 1 |
| 24°F | Nov 6 | Nov 11 | Nov 16 | Nov 21 | Nov 25 | Nov 29 | Dec 2 | Dec 6 | Dec 12 |
| 20°F | Nov 17 | Nov 24 | Nov 29 | Dec 3 | Dec 7 | Dec 12 | Dec 18 | Dec 24 | Jan 2 |
| 16°F | Nov 30 | Dec 8 | Dec 14 | Dec 20 | Dec 25 | Dec 31 | Jan 4 | Jan 11 | Jan 18 |
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: Tulsa Intl Ap, Ok, about 6.8 miles away@if(!empty($station['elevation_ft'])), at 650 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 Tulsa, OK?
On average, the last spring frost (32°F) around Tulsa, OK is about Mar 31. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 11.
When is the first frost in the fall?
The first fall frost around Tulsa, OK typically arrives about Nov 4. 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 31 on average, or Mar 11 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 220 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 74108 Planting calendar → Oklahoma frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026