Last spring frost
Apr 1
Frost Dates for Knoxville, TN
First fall frost
Nov 2
Growing season
215 days
Hardiness zone
7b
In an average year around Knoxville, TN, the last spring frost (32°F) is about Apr 1 and the first fall frost is about Nov 2, giving roughly a 215-day growing season. To be safe most years, wait until Mar 14 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 2 | Apr 14 | Mar 27 |
| Freeze (32°F) | Apr 17 | Apr 1 | Mar 14 |
| Hard (28°F) | Apr 5 | Mar 19 | Feb 28 |
| Severe (24°F) | Mar 27 | Mar 6 | Feb 12 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 2 | Apr 26 | Apr 22 | Apr 18 | Apr 14 | Apr 11 | Apr 7 | Apr 3 | Mar 27 |
| 32°F | Apr 17 | Apr 12 | Apr 7 | Apr 4 | Apr 1 | Mar 29 | Mar 24 | Mar 19 | Mar 14 |
| 28°F | Apr 5 | Apr 1 | Mar 28 | Mar 24 | Mar 19 | Mar 16 | Mar 12 | Mar 6 | Feb 28 |
| 24°F | Mar 27 | Mar 19 | Mar 15 | Mar 11 | Mar 6 | Mar 2 | Feb 26 | Feb 21 | Feb 12 |
| 20°F | Mar 16 | Mar 9 | Mar 3 | Feb 26 | Feb 20 | Feb 15 | Feb 7 | Feb 1 | Jan 22 |
| 16°F | Mar 4 | Feb 25 | Feb 15 | Feb 7 | Feb 1 | Jan 29 | Jan 23 | Jan 16 | Jan 6 |
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 12 | Oct 24 | Nov 5 |
| Freeze (32°F) | Oct 21 | Nov 2 | Nov 15 |
| Hard (28°F) | Nov 1 | Nov 13 | Dec 1 |
| Severe (24°F) | Nov 11 | Nov 27 | Dec 22 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 12 | Oct 16 | Oct 20 | Oct 22 | Oct 24 | Oct 26 | Oct 30 | Nov 1 | Nov 5 |
| 32°F | Oct 21 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 4 | Nov 7 | Nov 10 | Nov 15 |
| 28°F | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 16 | Nov 20 | Nov 23 | Dec 1 |
| 24°F | Nov 11 | Nov 15 | Nov 19 | Nov 23 | Nov 27 | Dec 1 | Dec 4 | Dec 11 | Dec 22 |
| 20°F | Nov 23 | Nov 30 | Dec 4 | Dec 9 | Dec 16 | Dec 22 | Dec 29 | Jan 2 | Jan 9 |
| 16°F | Dec 6 | Dec 15 | Dec 23 | Dec 29 | Jan 2 | Jan 6 | Jan 12 | Jan 17 | Jan 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
@endif These dates are computed from the nearest official weather station with long-term records: Knoxville Mcghee Tyson Ap, Tn, about 7.1 miles away@if(!empty($station['elevation_ft'])), at 962 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 Knoxville, TN?
On average, the last spring frost (32°F) around Knoxville, TN is about Apr 1. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 14.
When is the first frost in the fall?
The first fall frost around Knoxville, TN typically arrives about Nov 2. 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 1 on average, or Mar 14 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 215 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 37922 Planting calendar → Tennessee frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026