Frost dates for 51603 — Shenandoah, IA
Last spring frostApr 20median date
First fall frostOct 17median date
Growing season180 daysfrost-free
Hardiness zone5bZone 5b
How Shenandoah compares
- In 8 years out of 10, the last spring frost in Shenandoah falls between April 5 and May 3, a 28-day window. The first fall frost falls between October 1 and October 29.
- The median last frost is 8 days earlier than the Iowa median of Apr 28.
- Its 180-day growing season is longer than 88% of the 934 Iowa places with a regular frost season (state median 165 days).
- The last frost is 11 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 137 nights a year at or below 32°F.
- Compared with Bellevue, NE, 63 km away, the last frost here is 3 days later than there and the growing season is 5 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 5 |
| 50% (median) | April 20 |
| 10% (safe for tender plants) | May 3 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 1 |
| 50% (median) | October 17 |
| 90% (late) | October 29 |
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 Shenandoah, IA
Frost dates for 51603 — Shenandoah, IA — last frost Apr 20, first frost Oct 17, zone 5b. whenisthelastfrost.com
Crop
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Start indoors: Jan 26 to Feb 9Transplant outside: Mar 23 to Apr 6
Start indoors: Feb 9 to Feb 23Transplant outside: May 4 to May 18
Start indoors: Feb 9 to Feb 23Transplant outside: May 4 to May 18
Start indoors: Feb 23 to Mar 9Transplant outside: Apr 27 to May 11
Start indoors: Feb 23 to Mar 9Transplant outside: Mar 30 to Apr 13Sow outdoors: Mar 23 to Apr 27Plant for fall: Aug 22 to Sep 19
Start indoors: Feb 23 to Mar 9Transplant outside: Mar 23 to Apr 6Sow outdoors: Mar 23 to Apr 6Plant for fall: Aug 8 to Aug 29
Start indoors: Feb 23 to Mar 9Transplant outside: Apr 6 to Apr 20Plant for fall: Jul 11 to Aug 1
Start indoors: Feb 23 to Mar 9Transplant outside: Mar 30 to Apr 13Plant for fall: Jul 11 to Aug 1
Start indoors: Feb 23 to Mar 9Transplant outside: Apr 6 to Apr 20Plant for fall: Jul 11 to Aug 1
Start indoors: Mar 9 to Mar 23Transplant outside: May 11 to May 25Sow outdoors: May 11 to May 25
Start indoors: Mar 9 to Mar 23Transplant outside: Apr 27 to May 11
Sow outdoors: Mar 9 to Mar 30Plant for fall: Jul 25 to Aug 15
Sow outdoors: Mar 9 to Mar 30Plant for fall: Aug 22 to Sep 12
Sow outdoors: Mar 16 to Apr 27Plant for fall: Sep 5 to Sep 26
Start indoors: Mar 23 to Mar 30Transplant outside: May 4 to May 11Sow outdoors: Apr 27 to May 11Plant for fall: Aug 1 to Aug 15
Start indoors: Mar 23 to Mar 30Sow outdoors: Apr 27 to May 11Plant for fall: Aug 8 to Aug 22
Start indoors: Mar 23 to Mar 30Sow outdoors: Apr 27 to May 11
Start indoors: Mar 23 to Mar 30Transplant outside: May 4 to May 18
Sow outdoors: Mar 30 to Apr 27Plant for fall: Jul 25 to Aug 8
Sow outdoors: Mar 30 to Apr 27Plant for fall: Aug 8 to Aug 22
Sow outdoors: Mar 30 to Apr 20
Sow outdoors: Apr 6 to May 4Plant for fall: Aug 8 to Aug 22
Sow outdoors: Apr 6 to Apr 27Plant for fall: Aug 22 to Sep 12
Sow outdoors: Apr 27 to May 18Plant for fall: Aug 1 to Aug 15
Sow outdoors: Apr 27 to May 11
Transplant outside: May 4 to May 25
Plant for fall: Oct 3 to Nov 7
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Shenandoah, IA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 26 – Feb 9 | Mar 23 – Apr 6 | — | — |
| Peppers | Feb 9 – Feb 23 | May 4 – May 18 | — | — |
| Eggplant | Feb 9 – Feb 23 | May 4 – May 18 | — | — |
| Tomatoes | Feb 23 – Mar 9 | Apr 27 – May 11 | — | — |
| Lettuce | Feb 23 – Mar 9 | Mar 30 – Apr 13 | Mar 23 – Apr 27 | Aug 22 – Sep 19 |
| Kale | Feb 23 – Mar 9 | Mar 23 – Apr 6 | Mar 23 – Apr 6 | Aug 8 – Aug 29 |
| Broccoli | Feb 23 – Mar 9 | Apr 6 – Apr 20 | — | Jul 11 – Aug 1 |
| Cabbage | Feb 23 – Mar 9 | Mar 30 – Apr 13 | — | Jul 11 – Aug 1 |
| Cauliflower | Feb 23 – Mar 9 | Apr 6 – Apr 20 | — | Jul 11 – Aug 1 |
| Okra | Mar 9 – Mar 23 | May 11 – May 25 | May 11 – May 25 | — |
| Basil | Mar 9 – Mar 23 | Apr 27 – May 11 | — | — |
| Peas | — | — | Mar 9 – Mar 30 | Jul 25 – Aug 15 |
| Spinach | — | — | Mar 9 – Mar 30 | Aug 22 – Sep 12 |
| Radishes | — | — | Mar 16 – Apr 27 | Sep 5 – Sep 26 |
| Cucumbers | Mar 23 – Mar 30 | May 4 – May 11 | Apr 27 – May 11 | Aug 1 – Aug 15 |
| Zucchini & Summer Squash | Mar 23 – Mar 30 | — | Apr 27 – May 11 | Aug 8 – Aug 22 |
| Winter Squash & Pumpkins | Mar 23 – Mar 30 | — | Apr 27 – May 11 | — |
| Melons & Watermelon | Mar 23 – Mar 30 | May 4 – May 18 | — | — |
| Carrots | — | — | Mar 30 – Apr 27 | Jul 25 – Aug 8 |
| Beets | — | — | Mar 30 – Apr 27 | Aug 8 – Aug 22 |
| Potatoes | — | — | Mar 30 – Apr 20 | — |
| Swiss Chard | — | — | Apr 6 – May 4 | Aug 8 – Aug 22 |
| Cilantro | — | — | Apr 6 – Apr 27 | Aug 22 – Sep 12 |
| Green Beans | — | — | Apr 27 – May 18 | Aug 1 – Aug 15 |
| Sweet Corn | — | — | Apr 27 – May 11 | — |
| Sweet Potatoes | — | May 4 – May 25 | — | — |
| Garlic | — | — | — | Oct 3 – Nov 7 |
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 Shenandoah, IA weather station, about 1 km away (elevation 1,001 ft (305 m)).
ZIP codes in Shenandoah: 51601 51603
Frost dates near Shenandoah
- Farragut Apr 20 · Oct 17
- Essex Apr 20 · Oct 17
- Imogene Apr 20 · Oct 17
- Coin Apr 20 · Oct 17
- Northboro Apr 20 · Oct 17
- Yorktown Apr 25 · Oct 11
- Randolph Apr 19 · Oct 19
- Riverton Apr 19 · Oct 19
Frequently asked questions
When is the last frost in Shenandoah, IA?
The median last spring frost in Shenandoah, IA is April 20. There is still about a 10% chance of frost after May 3, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Shenandoah, IA?
The median first fall frost is October 17, with about a 10% chance of frost before October 1.
How long is the growing season in Shenandoah, IA?
About 180 days between the median last spring frost and first fall frost.
What planting zone is Shenandoah, IA?
Shenandoah, IA is in USDA hardiness zone 5b.