Frost dates for 37938 — Knoxville, TN
How Knoxville compares
- In 8 years out of 10, the last spring frost in Knoxville falls between April 6 and May 9, a 33-day window. The first fall frost falls between October 11 and November 6.
- The median last frost is 15 days later than the Tennessee median of Apr 7.
- Its 186-day growing season is longer than 11% of the 548 Tennessee places with a regular frost season (state median 206 days).
- The last frost is 17 days later than the zone 7b median of Apr 5. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 7b chart.
- The weather station records an average of 101 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 6 |
| 50% (median) | April 22 |
| 10% (safe for tender plants) | May 9 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 11 |
| 50% (median) | October 25 |
| 90% (late) | November 6 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Knoxville, TN
Frost dates for 37938 — Knoxville, TN — last frost Apr 22, first frost Oct 25, zone 7b. whenisthelastfrost.com
When to plant vegetables in Knoxville, TN
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 28 – Feb 11 | Mar 25 – Apr 8 | — | — |
| Peppers | Feb 11 – Feb 25 | May 6 – May 20 | — | — |
| Eggplant | Feb 11 – Feb 25 | May 6 – May 20 | — | — |
| Tomatoes | Feb 25 – Mar 11 | Apr 29 – May 13 | — | — |
| Lettuce | Feb 25 – Mar 11 | Apr 1 – Apr 15 | Mar 25 – Apr 29 | Aug 30 – Sep 27 |
| Kale | Feb 25 – Mar 11 | Mar 25 – Apr 8 | Mar 25 – Apr 8 | Aug 16 – Sep 6 |
| Broccoli | Feb 25 – Mar 11 | Apr 8 – Apr 22 | — | Jul 19 – Aug 9 |
| Cabbage | Feb 25 – Mar 11 | Apr 1 – Apr 15 | — | Jul 19 – Aug 9 |
| Cauliflower | Feb 25 – Mar 11 | Apr 8 – Apr 22 | — | Jul 19 – Aug 9 |
| Okra | Mar 11 – Mar 25 | May 13 – May 27 | May 13 – May 27 | — |
| Basil | Mar 11 – Mar 25 | Apr 29 – May 13 | — | — |
| Peas | — | — | Mar 11 – Apr 1 | Aug 2 – Aug 23 |
| Spinach | — | — | Mar 11 – Apr 1 | Aug 30 – Sep 20 |
| Radishes | — | — | Mar 18 – Apr 29 | Sep 13 – Oct 4 |
| Cucumbers | Mar 25 – Apr 1 | May 6 – May 13 | Apr 29 – May 13 | Aug 9 – Aug 23 |
| Zucchini & Summer Squash | Mar 25 – Apr 1 | — | Apr 29 – May 13 | Aug 16 – Aug 30 |
| Winter Squash & Pumpkins | Mar 25 – Apr 1 | — | Apr 29 – May 13 | — |
| Melons & Watermelon | Mar 25 – Apr 1 | May 6 – May 20 | — | — |
| Carrots | — | — | Apr 1 – Apr 29 | Aug 2 – Aug 16 |
| Beets | — | — | Apr 1 – Apr 29 | Aug 16 – Aug 30 |
| Potatoes | — | — | Apr 1 – Apr 22 | — |
| Swiss Chard | — | — | Apr 8 – May 6 | Aug 16 – Aug 30 |
| Cilantro | — | — | Apr 8 – Apr 29 | Aug 30 – Sep 20 |
| Green Beans | — | — | Apr 29 – May 20 | Aug 9 – Aug 23 |
| Sweet Corn | — | — | Apr 29 – May 13 | — |
| Sweet Potatoes | — | May 6 – May 27 | — | — |
| Garlic | — | — | — | Oct 11 – Nov 15 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Norris, TN weather station, 16 km away (elevation 1,109 ft (338 m)).
ZIP codes in Knoxville: 37901 37902 37909 37912 37914 37915 37916 37917 37918 37919 37920 37921 37922 37923 37924 37927 37928 37929 37930 37931 37932 37933 37934 37938 37939 37940 37950 37995 37996 37997 37998
Frost dates near Knoxville
- Heiskell Apr 22 · Oct 25
- Powell Apr 11 · Oct 28
- Corryton Apr 22 · Oct 25
- Andersonville Apr 22 · Oct 25
- Norris Apr 22 · Oct 25
- Maynardville Apr 22 · Oct 25
- Mascot Apr 6 · Oct 29
- Luttrell Apr 22 · Oct 25
Frequently asked questions
When is the last frost in Knoxville, TN?
The median last spring frost in Knoxville, TN is April 22. There is still about a 10% chance of frost after May 9, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Knoxville, TN?
The median first fall frost is October 25, with about a 10% chance of frost before October 11.
How long is the growing season in Knoxville, TN?
About 186 days between the median last spring frost and first fall frost.
What planting zone is Knoxville, TN?
Knoxville, TN is in USDA hardiness zone 7b.