Greenly Garden

Frost dates and when to plant in Kentucky

United States

In Kentucky the last spring frost comes between 31 March (Bowling Green) and 12 April (Frankfort) — the median of 2016–2025 in 4 cities. The first autumn frost comes between 3 November (Frankfort) and 11 November (Louisville). The frost-free season lasts 205–224 days. Tomato: plant out into open ground 11 April – 22 July, earliest in Bowling Green, latest in Louisville.

Frost dates by city in Kentucky

CityLast spring frostFirst autumn frostFrost-free daysClimate zoneTomato: window
Bowling Green31 March10 November224210–269 frost-free days11 April – 21 July
Louisville6 April11 November219210–269 frost-free days16 April – 22 July
Lexington10 April7 November211210–269 frost-free days28 April – 18 July
Frankfort12 April3 November205150–209 frost-free days22 April – 14 July

Median of 2016–2025 for the 25 km grid cell of the city: the last day at or below 0 °C in spring and the first in autumn (ERA5 reanalysis via Open-Meteo). In a cold year a frost can come a week or two later — Greenly warns 48 hours ahead.

When to plant in Kentucky: windows by crop

The earliest start and the latest end among the cities here, each with its city; every city’s own window is on its page. Each window starts on the Greenly calendar date and ends on the last day that still leaves the crop’s days to harvest (from its card) before the average first autumn frost, plus six weeks of picking for crops harvested over weeks (tomatoes, peppers, aubergines, cucumbers, courgettes, pumpkins, watermelons, beans) — our rule; earlier in the window is safer.

CropPlanting out or sowing
Tomato11 April (Bowling Green) – 22 July (Louisville)
Cucumber4 May (Bowling Green) – 27 August (Louisville)
Bell Pepper, Eggplant4 May (Bowling Green) – 22 July (Louisville)
Zucchini4 May (Bowling Green) – 25 August (Louisville)
Pumpkin4 May (Bowling Green) – 17 July (Louisville)
Watermelon4 May (Bowling Green) – 2 August (Louisville)
Peas10 March (Bowling Green) – 29 August (Louisville)
Garlic, Tulip, Daffodil, Crocus, HyacinthAutumn planting: 4 October (Frankfort) – end of December (Louisville)

Weather by month in Kentucky

Across the 4 cities the warmest month is July (average days 30.1 … 31.7 °C) and the coldest January (average nights -2.8 … -1.1 °C). Every city averages below 0 °C at night in January.

MonthDay, °CNight, °CRain, mm
January5.8 … 7.6 °C-2.8 … -1.1 °C105
February10.1 … 11.8 °C-0.3 … 1.5 °C135
March14.2 … 16.2 °C3.3 … 5.3 °C118
April18.6 … 20.4 °C7.5 … 9.1 °C136
May23.5 … 25.1 °C13.2 … 14.8 °C120
June28.5 … 30 °C17.6 … 19.1 °C117
July30.1 … 31.7 °C20.1 … 21.6 °C129
August29.1 … 30.4 °C19 … 20.4 °C94
September26.6 … 28.1 °C16.2 … 17.5 °C91
October20.6 … 22.1 °C10.3 … 11.7 °C91
November13 … 14.8 °C3.5 … 5 °C89
December8.6 … 10.5 °C0 … 1.8 °C103

Day and night: the lowest … highest monthly average among the cities; rain: the middle city (ERA5 via Open-Meteo).

What to plant month by month: the South

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