Mobile, Alabama: planting zone & frost dates
Mobile is in USDA plant hardiness zone 9a, where the average coldest winter night reaches 20 to 25°F (-6.7 to -3.9°C). The typical last spring frost is around Mar 3 and the first fall frost around Nov 28.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | Mar 15 | Nov 15 |
| Typical planning date (30% risk) | Mar 3 | Nov 28 |
| Median (50%) | Feb 21 | Dec 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 MOBILE DWTN AP, AL (USW00013838), 3.7 mi (6.0 km) from the city center and 3 ft higher than the city center (+1 m). Record used for the 1991–2020 normals: 24 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Mobile
All 18 ZIP codes covering Mobile are in zone 9a.
Vegetable planting calendar for Mobile
Dates are counted from the 30%-risk frost dates above (last frost Mar 3, first frost Nov 28). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Jan 6 – Jan 20 | Mar 10 – Mar 24 | — | — |
| Pepper | Dec 23 – Jan 6 | Mar 17 – Mar 31 | — | — |
| Lettuce | Jan 20 – Feb 3 | Feb 17 – Mar 10 | Feb 3 – Mar 17 | Sep 19 – Oct 17 |
| Green Beans | — | — | Mar 10 – Apr 14 | Sep 5 – Sep 19 |
| Sweet Corn | — | — | Mar 10 – Apr 7 | — |
| Zucchini & Summer Squash | Feb 3 – Feb 10 | Mar 10 – Mar 24 | Mar 10 – Mar 31 | Sep 5 – Sep 19 |
| Cucumber | Feb 3 – Feb 10 | Mar 17 – Mar 24 | Mar 10 – Mar 31 | Sep 5 – Sep 19 |
| Carrot | — | — | Feb 10 – Mar 17 | Sep 5 – Sep 19 |
| Onion | Dec 9 – Dec 23 | Feb 3 – Feb 17 | — | — |
| Potato | — | Feb 3 – Feb 24 | — | — |
| Basil | Jan 20 – Feb 3 | Mar 17 – Mar 31 | Mar 17 – Apr 7 | — |
| Spinach | — | — | Jan 20 – Feb 17 | Oct 3 – Oct 31 |
| Kale | Jan 6 – Jan 20 | Feb 3 – Feb 24 | Feb 3 – Feb 24 | Sep 19 – Oct 17 |
| Broccoli | Jan 6 – Jan 20 | Feb 17 – Mar 10 | — | Sep 5 – Sep 19 |
| Peas | — | — | Jan 20 – Feb 10 | Sep 19 – Oct 3 |
| Eggplant | Dec 23 – Jan 6 | Mar 17 – Mar 31 | — | — |
| Cabbage | Jan 6 – Jan 20 | Feb 3 – Feb 17 | — | Sep 5 – Sep 19 |
| Radish | — | — | Jan 27 – Mar 17 | Oct 17 – Nov 14 |
| Strawberry | — | Feb 3 – Feb 24 | — | — |
| Beets | — | — | Feb 10 – Mar 24 | Sep 19 – Oct 3 |
Nearby cities in Alabama
- Montgomery — zone 8b, last frost Mar 13, first frost Nov 9
- Tuscaloosa — zone 8b, last frost Mar 25, first frost Nov 5
- Hoover — zone 8b, last frost Mar 29, first frost Nov 2
- Birmingham — zone 8a, last frost Mar 30, first frost Nov 6
- Auburn — zone 8b, last frost Mar 21, first frost Nov 10
- Huntsville — zone 8a, last frost Mar 31, first frost Nov 2
More: all Alabama cities · other zone 9a cities: San Antonio, TX, Austin, TX, Seattle, WA, Las Vegas, NV, Portland, OR, Tucson, AZ, Baton Rouge, LA, Tallahassee, FL
Mobile gardening questions
When is the last frost in Mobile, AL?
Plan around Mar 3. At NOAA's Mobile Dwtn Airport, AL station, 3.7 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 Feb 21, and after Mar 15 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Feb 2. Springs here are erratic: 49 days separate the 90% and 10% dates, versus a median of 36 days for cities on this site, so watch the forecast rather than the calendar.
When should I plant tomatoes in Mobile, AL?
Start seeds indoors Jan 6 – Jan 20 and set transplants outside Mar 10 – Mar 24, once nights stay above 50°F and the soil is near 60°F. With about 270 frost-free days, frost is not the main limit — fruit set drops when nights stay above about 75°F, so early plantings tend to do best. More: tomato planting dates by zone.
How long is the growing season in Mobile?
About 292 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 257 days, and in 1 year in 10 it runs 326 days or more. In fall there is a 10% chance of frost by Nov 15 and a 30% chance by Nov 28. That is the longest of the 7 Alabama cities on this site.
When should I plant a fall garden in Mobile?
Count back from the first fall frost (Nov 28): transplant broccoli Sep 5 – Sep 19; sow kale Sep 19 – Oct 17; sow lettuce Sep 19 – Oct 17; sow radishes Oct 17 – Nov 14. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Dec 30. How the math works: succession and fall planting.
Did Mobile's hardiness zone change on the 2023 map?
Yes. Most of Mobile was zone 8b on the 2012 map and is zone 9a 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 Mobile compare with Gulfport, MS?
Both are in zone 9a. The typical last spring frost in Mobile (Mar 3) comes about the same time as in Gulfport, MS (Mar 5), 60 miles away, and the first fall frost is Nov 28 versus Nov 25. The two cities use different NOAA stations.