Kelley, IA frost dates
How Kelley compares
- In 8 years out of 10, the last spring frost in Kelley falls between April 11 and May 9, a 28-day window. The first fall frost falls between September 23 and October 21.
- The median last frost is 2 days earlier than the Iowa median of Apr 28.
- Its 165-day growing season is longer than 46% of the 934 Iowa places with a regular frost season (state median 165 days).
- The last frost is 5 days earlier than the zone 5b median of May 1. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5b chart.
- The weather station records an average of 147 nights a year at or below 32°F.
- Kelley shares its weather station with Ames, IA, 10 km away, so the two have the same frost dates.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 11 |
| 50% (median) | April 26 |
| 10% (safe for tender plants) | May 9 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 23 |
| 50% (median) | October 8 |
| 90% (late) | October 21 |
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 Kelley, IA
Kelley, IA frost dates — last frost Apr 26, first frost Oct 8, zone 5b. whenisthelastfrost.com
When to plant vegetables in Kelley, IA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 1 – Feb 15 | Mar 29 – Apr 12 | — | — |
| Peppers | Feb 15 – Mar 1 | May 10 – May 24 | — | — |
| Eggplant | Feb 15 – Mar 1 | May 10 – May 24 | — | — |
| Tomatoes | Mar 1 – Mar 15 | May 3 – May 17 | — | — |
| Lettuce | Mar 1 – Mar 15 | Apr 5 – Apr 19 | Mar 29 – May 3 | Aug 13 – Sep 10 |
| Kale | Mar 1 – Mar 15 | Mar 29 – Apr 12 | Mar 29 – Apr 12 | Jul 30 – Aug 20 |
| Broccoli | Mar 1 – Mar 15 | Apr 12 – Apr 26 | — | Jul 2 – Jul 23 |
| Cabbage | Mar 1 – Mar 15 | Apr 5 – Apr 19 | — | Jul 2 – Jul 23 |
| Cauliflower | Mar 1 – Mar 15 | Apr 12 – Apr 26 | — | Jul 2 – Jul 23 |
| Okra | Mar 15 – Mar 29 | May 17 – May 31 | May 17 – May 31 | — |
| Basil | Mar 15 – Mar 29 | May 3 – May 17 | — | — |
| Peas | — | — | Mar 15 – Apr 5 | Jul 16 – Aug 6 |
| Spinach | — | — | Mar 15 – Apr 5 | Aug 13 – Sep 3 |
| Radishes | — | — | Mar 22 – May 3 | Aug 27 – Sep 17 |
| Cucumbers | Mar 29 – Apr 5 | May 10 – May 17 | May 3 – May 17 | Jul 23 – Aug 6 |
| Zucchini & Summer Squash | Mar 29 – Apr 5 | — | May 3 – May 17 | Jul 30 – Aug 13 |
| Winter Squash & Pumpkins | Mar 29 – Apr 5 | — | May 3 – May 17 | — |
| Melons & Watermelon | Mar 29 – Apr 5 | May 10 – May 24 | — | — |
| Carrots | — | — | Apr 5 – May 3 | Jul 16 – Jul 30 |
| Beets | — | — | Apr 5 – May 3 | Jul 30 – Aug 13 |
| Potatoes | — | — | Apr 5 – Apr 26 | — |
| Swiss Chard | — | — | Apr 12 – May 10 | Jul 30 – Aug 13 |
| Cilantro | — | — | Apr 12 – May 3 | Aug 13 – Sep 3 |
| Green Beans | — | — | May 3 – May 24 | Jul 23 – Aug 6 |
| Sweet Corn | — | — | May 3 – May 17 | — |
| Sweet Potatoes | — | May 10 – May 31 | — | — |
| Garlic | — | — | — | Sep 24 – Oct 29 |
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 Ames Muni Ap, IA weather station, 6 km away (elevation 932 ft (284 m)).
Frost dates near Kelley
- Huxley Apr 26 · Oct 12
- Slater Apr 26 · Oct 12
- Ames Apr 26 · Oct 8
- Sheldahl Apr 19 · Oct 18
- Cambridge Apr 26 · Oct 12
- Luther Apr 23 · Oct 14
- Alleman Apr 23 · Oct 15
- Madrid Apr 23 · Oct 14
- Gilbert Apr 26 · Oct 8
- Nevada Apr 24 · Oct 12
Frequently asked questions
When is the last frost in Kelley, IA?
The median last spring frost in Kelley, IA is April 26. There is still about a 10% chance of frost after May 9, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Kelley, IA?
The median first fall frost is October 8, with about a 10% chance of frost before September 23.
How long is the growing season in Kelley, IA?
About 165 days between the median last spring frost and first fall frost.
What planting zone is Kelley, IA?
Kelley, IA is in USDA hardiness zone 5b.