Cincinnati, IA frost dates
Last spring frostApr 28median date
First fall frostOct 14median date
Growing season169 daysfrost-free
Hardiness zone5bZone 5b
How Cincinnati compares
- In 8 years out of 10, the last spring frost in Cincinnati falls between April 13 and May 11, a 28-day window. The first fall frost falls between September 26 and October 26.
- The median last frost is the same as the Iowa median of Apr 28.
- Its 169-day growing season is longer than 67% of the 934 Iowa places with a regular frost season (state median 165 days).
- The last frost is typical for zone 5b, where the median is May 1.
- The weather station records an average of 132 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 13 |
| 50% (median) | April 28 |
| 10% (safe for tender plants) | May 11 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 26 |
| 50% (median) | October 14 |
| 90% (late) | October 26 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Cincinnati, IA
Cincinnati, IA frost dates — last frost Apr 28, first frost Oct 14, zone 5b. whenisthelastfrost.com
Crop
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Start indoors: Feb 3 to Feb 17Transplant outside: Mar 31 to Apr 14
Start indoors: Feb 17 to Mar 3Transplant outside: May 12 to May 26
Start indoors: Feb 17 to Mar 3Transplant outside: May 12 to May 26
Start indoors: Mar 3 to Mar 17Transplant outside: May 5 to May 19
Start indoors: Mar 3 to Mar 17Transplant outside: Apr 7 to Apr 21Sow outdoors: Mar 31 to May 5Plant for fall: Aug 19 to Sep 16
Start indoors: Mar 3 to Mar 17Transplant outside: Mar 31 to Apr 14Sow outdoors: Mar 31 to Apr 14Plant for fall: Aug 5 to Aug 26
Start indoors: Mar 3 to Mar 17Transplant outside: Apr 14 to Apr 28Plant for fall: Jul 8 to Jul 29
Start indoors: Mar 3 to Mar 17Transplant outside: Apr 7 to Apr 21Plant for fall: Jul 8 to Jul 29
Start indoors: Mar 3 to Mar 17Transplant outside: Apr 14 to Apr 28Plant for fall: Jul 8 to Jul 29
Start indoors: Mar 17 to Mar 31Transplant outside: May 19 to Jun 2Sow outdoors: May 19 to Jun 2
Start indoors: Mar 17 to Mar 31Transplant outside: May 5 to May 19
Sow outdoors: Mar 17 to Apr 7Plant for fall: Jul 22 to Aug 12
Sow outdoors: Mar 17 to Apr 7Plant for fall: Aug 19 to Sep 9
Sow outdoors: Mar 24 to May 5Plant for fall: Sep 2 to Sep 23
Start indoors: Mar 31 to Apr 7Transplant outside: May 12 to May 19Sow outdoors: May 5 to May 19Plant for fall: Jul 29 to Aug 12
Start indoors: Mar 31 to Apr 7Sow outdoors: May 5 to May 19Plant for fall: Aug 5 to Aug 19
Start indoors: Mar 31 to Apr 7Sow outdoors: May 5 to May 19
Start indoors: Mar 31 to Apr 7Transplant outside: May 12 to May 26
Sow outdoors: Apr 7 to May 5Plant for fall: Jul 22 to Aug 5
Sow outdoors: Apr 7 to May 5Plant for fall: Aug 5 to Aug 19
Sow outdoors: Apr 7 to Apr 28
Sow outdoors: Apr 14 to May 12Plant for fall: Aug 5 to Aug 19
Sow outdoors: Apr 14 to May 5Plant for fall: Aug 19 to Sep 9
Sow outdoors: May 5 to May 26Plant for fall: Jul 29 to Aug 12
Sow outdoors: May 5 to May 19
Transplant outside: May 12 to Jun 2
Plant for fall: Sep 30 to Nov 4
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Cincinnati, IA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 3 – Feb 17 | Mar 31 – Apr 14 | — | — |
| Peppers | Feb 17 – Mar 3 | May 12 – May 26 | — | — |
| Eggplant | Feb 17 – Mar 3 | May 12 – May 26 | — | — |
| Tomatoes | Mar 3 – Mar 17 | May 5 – May 19 | — | — |
| Lettuce | Mar 3 – Mar 17 | Apr 7 – Apr 21 | Mar 31 – May 5 | Aug 19 – Sep 16 |
| Kale | Mar 3 – Mar 17 | Mar 31 – Apr 14 | Mar 31 – Apr 14 | Aug 5 – Aug 26 |
| Broccoli | Mar 3 – Mar 17 | Apr 14 – Apr 28 | — | Jul 8 – Jul 29 |
| Cabbage | Mar 3 – Mar 17 | Apr 7 – Apr 21 | — | Jul 8 – Jul 29 |
| Cauliflower | Mar 3 – Mar 17 | Apr 14 – Apr 28 | — | Jul 8 – Jul 29 |
| Okra | Mar 17 – Mar 31 | May 19 – Jun 2 | May 19 – Jun 2 | — |
| Basil | Mar 17 – Mar 31 | May 5 – May 19 | — | — |
| Peas | — | — | Mar 17 – Apr 7 | Jul 22 – Aug 12 |
| Spinach | — | — | Mar 17 – Apr 7 | Aug 19 – Sep 9 |
| Radishes | — | — | Mar 24 – May 5 | Sep 2 – Sep 23 |
| Cucumbers | Mar 31 – Apr 7 | May 12 – May 19 | May 5 – May 19 | Jul 29 – Aug 12 |
| Zucchini & Summer Squash | Mar 31 – Apr 7 | — | May 5 – May 19 | Aug 5 – Aug 19 |
| Winter Squash & Pumpkins | Mar 31 – Apr 7 | — | May 5 – May 19 | — |
| Melons & Watermelon | Mar 31 – Apr 7 | May 12 – May 26 | — | — |
| Carrots | — | — | Apr 7 – May 5 | Jul 22 – Aug 5 |
| Beets | — | — | Apr 7 – May 5 | Aug 5 – Aug 19 |
| Potatoes | — | — | Apr 7 – Apr 28 | — |
| Swiss Chard | — | — | Apr 14 – May 12 | Aug 5 – Aug 19 |
| Cilantro | — | — | Apr 14 – May 5 | Aug 19 – Sep 9 |
| Green Beans | — | — | May 5 – May 26 | Jul 29 – Aug 12 |
| Sweet Corn | — | — | May 5 – May 19 | — |
| Sweet Potatoes | — | May 12 – Jun 2 | — | — |
| Garlic | — | — | — | Sep 30 – Nov 4 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Centerville, IA weather station, 11 km away (elevation 906 ft (276 m)).
Frost dates near Cincinnati
- Exline Apr 28 · Oct 14
- Centerville Apr 28 · Oct 14
- Mystic Apr 18 · Oct 23
- Plano Apr 28 · Oct 14
- Seymour Apr 21 · Oct 19
- Moulton Apr 28 · Oct 14
- Udell Apr 18 · Oct 23
- Promise City Apr 21 · Oct 19
- Moravia Apr 18 · Oct 23
- Unionville Apr 18 · Oct 23
Frequently asked questions
When is the last frost in Cincinnati, IA?
The median last spring frost in Cincinnati, IA is April 28. There is still about a 10% chance of frost after May 11, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Cincinnati, IA?
The median first fall frost is October 14, with about a 10% chance of frost before September 26.
How long is the growing season in Cincinnati, IA?
About 169 days between the median last spring frost and first fall frost.
What planting zone is Cincinnati, IA?
Cincinnati, IA is in USDA hardiness zone 5b.