Walnut, IA frost dates
Last spring frostApr 30median date
First fall frostOct 2median date
Growing season155 daysfrost-free
Hardiness zone5aZone 5a
How Walnut compares
- In 8 years out of 10, the last spring frost in Walnut falls between April 17 and May 15, a 28-day window. The first fall frost falls between September 17 and October 16.
- The median last frost is 2 days later than the Iowa median of Apr 28.
- Its 155-day growing season is longer than 13% of the 934 Iowa places with a regular frost season (state median 165 days).
- The last frost is typical for zone 5a, where the median is May 3.
- The weather station records an average of 152 nights a year at or below 32°F.
- Compared with Council Bluffs, IA, 58 km away, the last frost here is 12 days later than there and the growing season is 31 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 17 |
| 50% (median) | April 30 |
| 10% (safe for tender plants) | May 15 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 17 |
| 50% (median) | October 2 |
| 90% (late) | October 16 |
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 Walnut, IA
Walnut, IA frost dates — last frost Apr 30, first frost Oct 2, zone 5a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 5 to Feb 19Transplant outside: Apr 2 to Apr 16
Start indoors: Feb 19 to Mar 5Transplant outside: May 14 to May 28
Start indoors: Feb 19 to Mar 5Transplant outside: May 14 to May 28
Start indoors: Mar 5 to Mar 19Transplant outside: May 7 to May 21
Start indoors: Mar 5 to Mar 19Transplant outside: Apr 9 to Apr 23Sow outdoors: Apr 2 to May 7Plant for fall: Aug 7 to Sep 4
Start indoors: Mar 5 to Mar 19Transplant outside: Apr 2 to Apr 16Sow outdoors: Apr 2 to Apr 16Plant for fall: Jul 24 to Aug 14
Start indoors: Mar 5 to Mar 19Transplant outside: Apr 16 to Apr 30Plant for fall: Jun 26 to Jul 17
Start indoors: Mar 5 to Mar 19Transplant outside: Apr 9 to Apr 23Plant for fall: Jun 26 to Jul 17
Start indoors: Mar 5 to Mar 19Transplant outside: Apr 16 to Apr 30Plant for fall: Jun 26 to Jul 17
Start indoors: Mar 19 to Apr 2Transplant outside: May 21 to Jun 4Sow outdoors: May 21 to Jun 4
Start indoors: Mar 19 to Apr 2Transplant outside: May 7 to May 21
Sow outdoors: Mar 19 to Apr 9Plant for fall: Jul 10 to Jul 31
Sow outdoors: Mar 19 to Apr 9Plant for fall: Aug 7 to Aug 28
Sow outdoors: Mar 26 to May 7Plant for fall: Aug 21 to Sep 11
Start indoors: Apr 2 to Apr 9Transplant outside: May 14 to May 21Sow outdoors: May 7 to May 21Plant for fall: Jul 17 to Jul 31
Start indoors: Apr 2 to Apr 9Sow outdoors: May 7 to May 21Plant for fall: Jul 24 to Aug 7
Start indoors: Apr 2 to Apr 9Sow outdoors: May 7 to May 21
Start indoors: Apr 2 to Apr 9Transplant outside: May 14 to May 28
Sow outdoors: Apr 9 to May 7Plant for fall: Jul 10 to Jul 24
Sow outdoors: Apr 9 to May 7Plant for fall: Jul 24 to Aug 7
Sow outdoors: Apr 9 to Apr 30
Sow outdoors: Apr 16 to May 14Plant for fall: Jul 24 to Aug 7
Sow outdoors: Apr 16 to May 7Plant for fall: Aug 7 to Aug 28
Sow outdoors: May 7 to May 28Plant for fall: Jul 17 to Jul 31
Sow outdoors: May 7 to May 21
Transplant outside: May 14 to Jun 4
Plant for fall: Sep 18 to Oct 23
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Walnut, IA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 5 – Feb 19 | Apr 2 – Apr 16 | — | — |
| Peppers | Feb 19 – Mar 5 | May 14 – May 28 | — | — |
| Eggplant | Feb 19 – Mar 5 | May 14 – May 28 | — | — |
| Tomatoes | Mar 5 – Mar 19 | May 7 – May 21 | — | — |
| Lettuce | Mar 5 – Mar 19 | Apr 9 – Apr 23 | Apr 2 – May 7 | Aug 7 – Sep 4 |
| Kale | Mar 5 – Mar 19 | Apr 2 – Apr 16 | Apr 2 – Apr 16 | Jul 24 – Aug 14 |
| Broccoli | Mar 5 – Mar 19 | Apr 16 – Apr 30 | — | Jun 26 – Jul 17 |
| Cabbage | Mar 5 – Mar 19 | Apr 9 – Apr 23 | — | Jun 26 – Jul 17 |
| Cauliflower | Mar 5 – Mar 19 | Apr 16 – Apr 30 | — | Jun 26 – Jul 17 |
| Okra | Mar 19 – Apr 2 | May 21 – Jun 4 | May 21 – Jun 4 | — |
| Basil | Mar 19 – Apr 2 | May 7 – May 21 | — | — |
| Peas | — | — | Mar 19 – Apr 9 | Jul 10 – Jul 31 |
| Spinach | — | — | Mar 19 – Apr 9 | Aug 7 – Aug 28 |
| Radishes | — | — | Mar 26 – May 7 | Aug 21 – Sep 11 |
| Cucumbers | Apr 2 – Apr 9 | May 14 – May 21 | May 7 – May 21 | Jul 17 – Jul 31 |
| Zucchini & Summer Squash | Apr 2 – Apr 9 | — | May 7 – May 21 | Jul 24 – Aug 7 |
| Winter Squash & Pumpkins | Apr 2 – Apr 9 | — | May 7 – May 21 | — |
| Melons & Watermelon | Apr 2 – Apr 9 | May 14 – May 28 | — | — |
| Carrots | — | — | Apr 9 – May 7 | Jul 10 – Jul 24 |
| Beets | — | — | Apr 9 – May 7 | Jul 24 – Aug 7 |
| Potatoes | — | — | Apr 9 – Apr 30 | — |
| Swiss Chard | — | — | Apr 16 – May 14 | Jul 24 – Aug 7 |
| Cilantro | — | — | Apr 16 – May 7 | Aug 7 – Aug 28 |
| Green Beans | — | — | May 7 – May 28 | Jul 17 – Jul 31 |
| Sweet Corn | — | — | May 7 – May 21 | — |
| Sweet Potatoes | — | May 14 – Jun 4 | — | — |
| Garlic | — | — | — | Sep 18 – Oct 23 |
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 Atlantic 1 Ne, IA weather station, 18 km away (elevation 1,152 ft (351 m)).
Frost dates near Walnut
- Marne Apr 30 · Oct 2
- Avoca Apr 27 · Oct 9
- Hancock Apr 23 · Oct 14
- Harlan Apr 27 · Oct 9
- Elk Horn May 2 · Oct 3
- Atlantic Apr 30 · Oct 2
- Shelby Apr 27 · Oct 9
- Oakland Apr 23 · Oct 14
- Lewis Apr 30 · Oct 2
- Brayton Apr 30 · Oct 2
Frequently asked questions
When is the last frost in Walnut, IA?
The median last spring frost in Walnut, IA is April 30. There is still about a 10% chance of frost after May 15, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Walnut, IA?
The median first fall frost is October 2, with about a 10% chance of frost before September 17.
How long is the growing season in Walnut, IA?
About 155 days between the median last spring frost and first fall frost.
What planting zone is Walnut, IA?
Walnut, IA is in USDA hardiness zone 5a.