Fort Smith, Arkansas: planting zone & frost dates
Fort Smith is in USDA plant hardiness zone 8a, where the average coldest winter night reaches 10 to 15°F (-12.2 to -9.4°C). The typical last spring frost is around Apr 3 and the first fall frost around Nov 1.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | Apr 11 | Oct 23 |
| Typical planning date (30% risk) | Apr 3 | Nov 1 |
| Median (50%) | Mar 25 | Nov 6 |
How to read this: after the spring "10% risk" date, a 32°F frost happens in only about 1 year in 10. In fall, the "10% risk" date is the early end — a frost before it happens about 1 year in 10.
Frost data comes from NOAA station FT SMITH RGNL AP, AR (USW00013964), 1.2 mi (2.0 km) from the city center and 13 ft lower than the city center (-4 m). Record used for the 1991–2020 normals: 27 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Fort Smith
All 6 ZIP codes covering Fort Smith are in zone 8a.
Vegetable planting calendar for Fort Smith
Dates are counted from the 30%-risk frost dates above (last frost Apr 3, first frost Nov 1). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Feb 6 – Feb 20 | Apr 10 – Apr 24 | — | — |
| Pepper | Jan 23 – Feb 6 | Apr 17 – May 1 | — | — |
| Lettuce | Feb 20 – Mar 6 | Mar 20 – Apr 10 | Mar 6 – Apr 17 | Aug 23 – Sep 20 |
| Green Beans | — | — | Apr 10 – May 15 | Aug 9 – Aug 23 |
| Sweet Corn | — | — | Apr 10 – May 8 | — |
| Zucchini & Summer Squash | Mar 6 – Mar 13 | Apr 10 – Apr 24 | Apr 10 – May 1 | Aug 9 – Aug 23 |
| Cucumber | Mar 6 – Mar 13 | Apr 17 – Apr 24 | Apr 10 – May 1 | Aug 9 – Aug 23 |
| Carrot | — | — | Mar 13 – Apr 17 | Aug 9 – Aug 23 |
| Onion | Jan 9 – Jan 23 | Mar 6 – Mar 20 | — | — |
| Potato | — | Mar 6 – Mar 27 | — | — |
| Basil | Feb 20 – Mar 6 | Apr 17 – May 1 | Apr 17 – May 8 | — |
| Spinach | — | — | Feb 20 – Mar 20 | Sep 6 – Oct 4 |
| Kale | Feb 6 – Feb 20 | Mar 6 – Mar 27 | Mar 6 – Mar 27 | Aug 23 – Sep 20 |
| Broccoli | Feb 6 – Feb 20 | Mar 20 – Apr 10 | — | Aug 9 – Aug 23 |
| Peas | — | — | Feb 20 – Mar 13 | Aug 23 – Sep 6 |
| Eggplant | Jan 23 – Feb 6 | Apr 17 – May 1 | — | — |
| Cabbage | Feb 6 – Feb 20 | Mar 6 – Mar 20 | — | Aug 9 – Aug 23 |
| Radish | — | — | Feb 27 – Apr 17 | Sep 20 – Oct 18 |
| Strawberry | — | Mar 6 – Mar 27 | — | — |
| Beets | — | — | Mar 13 – Apr 24 | Aug 23 – Sep 6 |
Nearby cities in Arkansas
- Fayetteville — zone 7a, last frost Apr 11, first frost Oct 25
- Springdale — zone 7a, last frost Apr 11, first frost Oct 25
- Little Rock — zone 8a, last frost Mar 28, first frost Nov 4
- Jonesboro — zone 8a, last frost Mar 31, first frost Nov 3
More: all Arkansas cities · other zone 8a cities: Charlotte, NC, Memphis, TN, Atlanta, GA, Raleigh, NC, Greensboro, NC, Durham, NC, Winston-Salem, NC, Chesapeake, VA
Fort Smith gardening questions
When is the last frost in Fort Smith, AR?
Plan around Apr 3. At NOAA's Ft Smith Regional Airport, AR station, 1.2 mi from the city center, there is a 30% chance of a 32°F frost after that date. Half of springs have their last frost by Mar 25, and after Apr 11 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Mar 11. The 90% and 10% dates are 38 days apart, close to the 36-day median for cities on this site.
When should I plant tomatoes in Fort Smith, AR?
Start seeds indoors Feb 6 – Feb 20 and set transplants outside Apr 10 – Apr 24, once nights stay above 50°F and the soil is near 60°F. That leaves 212 days between the 30% frost dates, enough for most varieties including 80–85-day slicers. More: tomato planting dates by zone.
How long is the growing season in Fort Smith?
About 224 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 202 days, and in 1 year in 10 it runs 248 days or more. In fall there is a 10% chance of frost by Oct 23 and a 30% chance by Nov 1. That ranks 3rd longest of 5 Arkansas cities on this site.
When should I plant a fall garden in Fort Smith?
Count back from the first fall frost (Nov 1): transplant broccoli Aug 9 – Aug 23; sow kale Aug 23 – Sep 20; sow lettuce Aug 23 – Sep 20; sow radishes Sep 20 – Oct 18. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 17. How the math works: succession and fall planting.
Did Fort Smith's hardiness zone change on the 2023 map?
Yes. Most of Fort Smith was zone 7b on the 2012 map and is zone 8a on the 2023 map — half a zone warmer, like about 56% of U.S. ZIP codes. The shift comes from a newer 1991–2020 averaging period plus more weather stations and better mapping; it does not mean last frost comes earlier. Why the 2023 map is warmer.
How does Fort Smith compare with Fayetteville, AR?
Fort Smith is zone 8a and Fayetteville is zone 7a. The typical last spring frost in Fort Smith (Apr 3) comes about 8 days earlier than in Fayetteville, AR (Apr 11), 51 miles away, and the first fall frost is Nov 1 versus Oct 25. Fort Smith sits about 914 ft lower, which explains part of the gap. The two cities use different NOAA stations.