Louisville, Kentucky: planting zone & frost dates
Louisville is in USDA plant hardiness zone 7a, where the average coldest winter night reaches 0 to 5°F (-17.8 to -15.0°C). The typical last spring frost is around Apr 13 and the first fall frost around Oct 29.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | Apr 23 | Oct 21 |
| Typical planning date (30% risk) | Apr 13 | Oct 29 |
| Median (50%) | Apr 6 | Nov 1 |
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 LOUISVILLE WFO, KY (USC00154958), 3.5 mi (5.6 km) from the city center and 112 ft higher than the city center (+34 m). Record used for the 1991–2020 normals: 24 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Louisville
All 18 ZIP codes covering Louisville are in zone 7a.
Vegetable planting calendar for Louisville
Dates are counted from the 30%-risk frost dates above (last frost Apr 13, first frost Oct 29). 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 16 – Mar 2 | Apr 20 – May 4 | — | — |
| Pepper | Feb 2 – Feb 16 | Apr 27 – May 11 | — | — |
| Lettuce | Mar 2 – Mar 16 | Mar 30 – Apr 20 | Mar 16 – Apr 27 | Aug 20 – Sep 17 |
| Green Beans | — | — | Apr 20 – May 25 | Aug 6 – Aug 20 |
| Sweet Corn | — | — | Apr 20 – May 18 | — |
| Zucchini & Summer Squash | Mar 16 – Mar 23 | Apr 20 – May 4 | Apr 20 – May 11 | Aug 6 – Aug 20 |
| Cucumber | Mar 16 – Mar 23 | Apr 27 – May 4 | Apr 20 – May 11 | Aug 6 – Aug 20 |
| Carrot | — | — | Mar 23 – Apr 27 | Aug 6 – Aug 20 |
| Onion | Jan 19 – Feb 2 | Mar 16 – Mar 30 | — | — |
| Potato | — | Mar 16 – Apr 6 | — | — |
| Basil | Mar 2 – Mar 16 | Apr 27 – May 11 | Apr 27 – May 18 | — |
| Spinach | — | — | Mar 2 – Mar 30 | Sep 3 – Oct 1 |
| Kale | Feb 16 – Mar 2 | Mar 16 – Apr 6 | Mar 16 – Apr 6 | Aug 20 – Sep 17 |
| Broccoli | Feb 16 – Mar 2 | Mar 30 – Apr 20 | — | Aug 6 – Aug 20 |
| Peas | — | — | Mar 2 – Mar 23 | Aug 20 – Sep 3 |
| Eggplant | Feb 2 – Feb 16 | Apr 27 – May 11 | — | — |
| Cabbage | Feb 16 – Mar 2 | Mar 16 – Mar 30 | — | Aug 6 – Aug 20 |
| Radish | — | — | Mar 9 – Apr 27 | Sep 17 – Oct 15 |
| Strawberry | — | Mar 16 – Apr 6 | — | — |
| Beets | — | — | Mar 23 – May 4 | Aug 20 – Sep 3 |
Nearby cities in Kentucky
- Lexington — zone 7a, last frost Apr 20, first frost Oct 23
- Bowling Green — zone 7a, last frost Apr 11, first frost Oct 26
More: all Kentucky cities · other zone 7a cities: Wichita, KS, Cleveland, OH, Lexington, KY, St. Louis, MO, Boise, ID, Amarillo, TX, Providence, RI, Paterson, NJ
Louisville gardening questions
When is the last frost in Louisville, KY?
Plan around Apr 13. At NOAA's Louisville Wfo, KY station, 3.5 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 Apr 6, and after Apr 23 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Mar 26. The 90% and 10% dates are 31 days apart, close to the 36-day median for cities on this site.
When should I plant tomatoes in Louisville, KY?
Start seeds indoors Feb 16 – Mar 2 and set transplants outside Apr 20 – May 4, once nights stay above 50°F and the soil is near 60°F. That leaves 199 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 Louisville?
About 209 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 187 days, and in 1 year in 10 it runs 229 days or more. In fall there is a 10% chance of frost by Oct 21 and a 30% chance by Oct 29. That is the longest of the 3 Kentucky cities on this site.
When should I plant a fall garden in Louisville?
Count back from the first fall frost (Oct 29): transplant broccoli Aug 6 – Aug 20; sow kale Aug 20 – Sep 17; sow lettuce Aug 20 – Sep 17; sow radishes Sep 17 – Oct 15. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 11. How the math works: succession and fall planting.
Did Louisville's hardiness zone change on the 2023 map?
Yes. Most of Louisville was zone 6b on the 2012 map and is zone 7a 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 Louisville compare with Lexington, KY?
Both are in zone 7a. The typical last spring frost in Louisville (Apr 13) comes about 7 days earlier than in Lexington, KY (Apr 20), 65 miles away, and the first fall frost is Oct 29 versus Oct 23. Louisville sits about 539 ft lower, which explains part of the gap. The two cities use different NOAA stations.