Greenly Garden

Frost dates and when to plant in Missouri

United States

In Missouri the last spring frost comes between 30 March (Joplin) and 7 April (Kansas City) — the median of 2016–2025 in 4 cities. The first autumn frost comes between 1 November (Kansas City) and 4 November (Jefferson City). The frost-free season lasts 208–216 days. Tomato: plant out into open ground 11 April – 15 July, earliest in Joplin, latest in St. Louis.

Frost dates by city in Missouri

CityLast spring frostFirst autumn frostFrost-free daysClimate zoneTomato: window
Joplin30 March1 November216210–269 frost-free days11 April – 12 July
Jefferson City5 April4 November213210–269 frost-free days23 April – 15 July
St. Louis6 April4 November212210–269 frost-free days18 April – 15 July
Kansas City7 April1 November208150–209 frost-free days18 April – 12 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 Missouri: 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 (Joplin) – 15 July (St. Louis)
Cucumber5 May (Joplin) – 20 August (St. Louis)
Bell Pepper, Eggplant5 May (Joplin) – 15 July (St. Louis)
Zucchini5 May (Joplin) – 18 August (St. Louis)
Pumpkin5 May (Joplin) – 10 July (St. Louis)
Watermelon5 May (Joplin) – 26 July (St. Louis)
Peas9 March (Joplin) – 22 August (St. Louis)
Garlic, Tulip, Daffodil, Crocus, HyacinthAutumn planting: 2 October (Kansas City) – end of December (Kansas City)

Weather by month in Missouri

Across the 4 cities the warmest month is July (average days 31.1 … 32.4 °C) and the coldest January (average nights -4.5 … -2.2 °C). Every city averages below 0 °C at night in January, February.

MonthDay, °CNight, °CRain, mm
January4.2 … 7.5 °C-4.5 … -2.2 °C65
February7.7 … 11 °C-2.6 … -0.2 °C62
March14.4 … 16.7 °C3.7 … 5.5 °C116
April19.1 … 20.5 °C8 … 9.3 °C141
May24.2 … 24.7 °C14 … 14.6 °C150
June30 … 30.6 °C19.4 … 20 °C120
July31.1 … 32.4 °C21.5 … 22 °C122
August29.5 … 31.4 °C20.3 … 21.1 °C118
September27.3 … 28.9 °C17.4 … 18.2 °C76
October20.6 … 22.2 °C10.9 … 11.8 °C98
November12.8 … 15.2 °C3.9 … 5.3 °C63
December7.9 … 10.6 °C-0.9 … 1.2 °C48

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 Northeast and Midwest

Other regions: United States

More about the United States