US Grow Zones

Bowling Green, Kentucky: planting zone & frost dates

Last updated · Sources: PRISM/OSU 2023 ZIP zone listings; NOAA NCEI 1991–2020 Climate Normals (station USW00093808); U.S. Census Bureau — see methodology

Bowling Green 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 11 and the first fall frost around Oct 26.

Hardiness zone7A0 to 5°F
Last spring frostApr 1130% chance of frost after
First fall frostOct 2630% chance of frost before
Growing season208 daysmedian frost-free days

Frost dates

ProbabilityLast spring frost (32°F)First fall frost (32°F)
Safer (10% risk)Apr 21Oct 20
Typical planning date (30% risk)Apr 11Oct 26
Median (50%)Apr 5Oct 31

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 BOWLING GREEN WARREN CO AP, KY (USW00093808), 1.0 mi (1.6 km) from the city center and about the same elevation as the city center (-0 m). Record used for the 1991–2020 normals: 29 years.

Frost probability in spring and fall, Bowling Green, KYChance of a 32°F frost in Bowling Green, KY, NOAA 1991–2020. Spring: the chance of another frost falls from 90% on Mar 20 to 10% on Apr 21. Fall: the chance that the first frost has arrived rises from 10% on Oct 20 to 90% on Nov 11.0%50%100%Spring: later frostMar 1Mar 15Apr 1Apr 1530%: Apr 11Fall: frost arrivedOct 15Nov 1Nov 15Dec 130%: Oct 2632°F frost28°F hard freezeplanning date
Shaded areas show the chance of a 32°F frost: falling through spring, rising through fall. The dashed line is the 28°F hard-freeze curve. Data: NOAA 1991–2020 Normals, station USW00093808.
Frost-free growing season in Bowling Green, KY1 in 10 risk: Apr 21 to Oct 20 (182 days); 3 in 10 risk: Apr 11 to Oct 26 (198 days); Median (50%): Apr 5 to Oct 31 (209 days); No 28°F freeze: Mar 24 to Nov 10 (231 days). In 9 of 10 years the 32°F-free season is at least 187 days.Frost-free days, spring to fallJFMAMJJASOND1 in 10 risk182 days3 in 10 risk198 daysMedian (50%)209 daysNo 28°F freeze231 days
Frost-free window at three risk levels, plus the window between 28°F hard freezes. Read about what the probabilities mean.

Why your yard may differ from the station: microclimates.

Hardiness zone across Bowling Green

All 3 ZIP codes covering Bowling Green are in zone 7a.

ZIP codes in Bowling Green and their zones
ZIPZoneShare of city land
421017a51.7%
421037a24.1%
421047a24.1%

Vegetable planting calendar for Bowling Green

Dates are counted from the 30%-risk frost dates above (last frost Apr 11, first frost Oct 26). Shift a week later in cold spots or low-lying ground.

CropStart indoorsTransplant / plant outDirect sowFall crop sow/plant
TomatoFeb 14 – Feb 28Apr 18 – May 2——
PepperJan 31 – Feb 14Apr 25 – May 9——
LettuceFeb 28 – Mar 14Mar 28 – Apr 18Mar 14 – Apr 25Aug 17 – Sep 14
Green Beans——Apr 18 – May 23Aug 3 – Aug 17
Sweet Corn——Apr 18 – May 16—
Zucchini & Summer SquashMar 14 – Mar 21Apr 18 – May 2Apr 18 – May 9Aug 3 – Aug 17
CucumberMar 14 – Mar 21Apr 25 – May 2Apr 18 – May 9Aug 3 – Aug 17
Carrot——Mar 21 – Apr 25Aug 3 – Aug 17
OnionJan 17 – Jan 31Mar 14 – Mar 28——
Potato—Mar 14 – Apr 4——
BasilFeb 28 – Mar 14Apr 25 – May 9Apr 25 – May 16—
Spinach——Feb 28 – Mar 28Aug 31 – Sep 28
KaleFeb 14 – Feb 28Mar 14 – Apr 4Mar 14 – Apr 4Aug 17 – Sep 14
BroccoliFeb 14 – Feb 28Mar 28 – Apr 18—Aug 3 – Aug 17
Peas——Feb 28 – Mar 21Aug 17 – Aug 31
EggplantJan 31 – Feb 14Apr 25 – May 9——
CabbageFeb 14 – Feb 28Mar 14 – Mar 28—Aug 3 – Aug 17
Radish——Mar 7 – Apr 25Sep 14 – Oct 12
Strawberry—Mar 14 – Apr 4——
Beets——Mar 21 – May 2Aug 17 – Aug 31

Nearby cities in Kentucky

More: all Kentucky cities · other zone 7a cities: Louisville, KY, Wichita, KS, Cleveland, OH, Lexington, KY, St. Louis, MO, Boise, ID, Amarillo, TX, Providence, RI

Bowling Green gardening questions

When is the last frost in Bowling Green, KY?

Plan around Apr 11. At NOAA's Bowling Green Warren County Airport, KY station, 1.0 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 5, and after Apr 21 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Mar 24. The 90% and 10% dates are 32 days apart, close to the 36-day median for cities on this site.

When should I plant tomatoes in Bowling Green, KY?

Start seeds indoors Feb 14 – Feb 28 and set transplants outside Apr 18 – May 2, once nights stay above 50°F and the soil is near 60°F. That leaves 198 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 Bowling Green?

About 208 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 20 and a 30% chance by Oct 26. That ranks 2nd longest of 3 Kentucky cities on this site.

When should I plant a fall garden in Bowling Green?

Count back from the first fall frost (Oct 26): transplant broccoli Aug 3 – Aug 17; sow kale Aug 17 – Sep 14; sow lettuce Aug 17 – Sep 14; sow radishes Sep 14 – Oct 12. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 10. How the math works: succession and fall planting.

Did Bowling Green's hardiness zone change on the 2023 map?

Yes. Most of Bowling Green 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 Bowling Green compare with Clarksville, TN?

Bowling Green is zone 7a and Clarksville is zone 7b. The typical last spring frost in Bowling Green (Apr 11) comes about the same time as in Clarksville, TN (Apr 10), 58 miles away, and the first fall frost is Oct 26 versus Oct 27. The two cities use different NOAA stations.