Last and first frost dates in Cincinnati

When is the last frost in Cincinnati?

The last frost in Cincinnati usually comes around 11 April: that is the median of 2016–2025, so in about half of those years the last night at or below 0 °C came later. Hardy crops start before it and frost-tender ones only after it: in the table below arugula can go into open ground from 21 March, while corn waits until 18 April. The first autumn frost follows around 9 November, about 212 days later: harvest or cover frost-tender crops before then.

When to sow and plant

Planting out: a week after the last frost once the soil is warm enough for the crop; frost-hardy crops three weeks before it; an unheated greenhouse three weeks earlier. Seedlings are sown so they are ready on that day. 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.

What planting zone is Cincinnati?

The official USDA map (2023, 1991–2020 data) puts the centre of Cincinnati (ZIP 45219) in zone 6b. Zone 6b stands for an average coldest night of -5 to 0 °F (-20.6 to -17.8 °C), so perennials hardy to zone 6b or a colder zone should come through a typical winter here.

Check the official USDA map for Cincinnati: USDA Plant Hardiness Zone Map.

When the soil warms up in Cincinnati

The day the top 7 cm of soil first averages each temperature over a week, median of 2016–2025 (ERA5 via Open-Meteo). The soil reaches 10 °C 24 days before the last spring frost and 15 °C 11 days after it.

Frost dates near Cincinnati

Of the nearest cities on our list, the last spring frost ends earliest in Louisville (6 April) and latest in Dayton (17 April).

Seeds, seedlings and markets in Cincinnati

Within 15 km of Cincinnati OpenStreetMap lists 10 garden centres, 6 markets and 2 farm shops (collected 20 October 2026). The nearest garden centre to the city centre is Fern, 2 km away.

• Fern — garden centre
  East McMillan Street 737, 45206 Cincinnati · 2 km
• Findlay Market — market
  Sun 10:00–16:00; Tue–Fri 09:00–18:00; Sat 08:00–18:00 · 2 km · findlaymarket.org
• Tewes Farm — farm shop
  Crescent Springs Pike 2801, 41018 · Mon–Tue, Thu–Fri 10:00–18:00; Sat 11:00–15:00 · 12 km · tewesfarm.com
• Gardens at the Village Green — garden centre
  Knowlton Street 1415, 45223 Cincinnati · 4 km · villagegreenfoundation.org
• B&D Asian Nepali Market — market
  Winton Road 9172, 45231 Cincinnati · 12 km
• McGlasson Farms — farm shop
  River Road 5832 · Mon–Fri 09:00–18:00; Sat–Sun 09:00–17:00 · 15 km · mcglassonfarms.com

• Where to buy seeds and seedlings in Cincinnati
• Selling your own harvest in the United States

Places: © OpenStreetMap contributors, ODbL.

Weather in Cincinnati by month

Average weather in Cincinnati over 2016–2025: the warmest month is July. Months that average 20 °C or more by day: May–October (20.1–30.1 °C). Months that average 30 °C or more by day: July (30.1 °C). Nights average below 0 °C in January (-3.9 °C), February (-1.6 °C) and December (-0.9 °C). About 1147 mm of rain falls in a year, on 135 days; May is the wettest month (125 mm) and September the driest (75 mm).

Average of the daily highs and lows, rain per month and days with at least 1 mm (ERA5 via Open-Meteo, the same grid cell as the frost dates).

Planted in autumn

From a month before the first autumn frost, so the roots grow before winter, to the late-planting limit on each crop’s page (about two weeks before the ground freezes, by ten years of weather).