Elma, IA frost dates
How Elma compares
- In 8 years out of 10, the last spring frost in Elma falls between April 17 and May 14, a 27-day window. The first fall frost falls between September 23 and October 18.
- The median last frost is 4 days later than the Iowa median of Apr 28.
- Its 156-day growing season is longer than 15% of the 934 Iowa places with a regular frost season (state median 165 days).
- The last frost is 6 days earlier than the zone 4b median of May 8. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 4b chart.
- The weather station records an average of 158 nights a year at or below 32°F.
- Compared with Rochester, MN, 84 km away, the last frost here is 2 days later than there and the growing season is 3 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 17 |
| 50% (median) | May 2 |
| 10% (safe for tender plants) | May 14 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 23 |
| 50% (median) | October 5 |
| 90% (late) | October 18 |
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 Elma, IA
Elma, IA frost dates — last frost May 2, first frost Oct 5, zone 4b. whenisthelastfrost.com
When to plant vegetables in Elma, IA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 7 – Feb 21 | Apr 4 – Apr 18 | — | — |
| Peppers | Feb 21 – Mar 7 | May 16 – May 30 | — | — |
| Eggplant | Feb 21 – Mar 7 | May 16 – May 30 | — | — |
| Tomatoes | Mar 7 – Mar 21 | May 9 – May 23 | — | — |
| Lettuce | Mar 7 – Mar 21 | Apr 11 – Apr 25 | Apr 4 – May 9 | Aug 10 – Sep 7 |
| Kale | Mar 7 – Mar 21 | Apr 4 – Apr 18 | Apr 4 – Apr 18 | Jul 27 – Aug 17 |
| Broccoli | Mar 7 – Mar 21 | Apr 18 – May 2 | — | Jun 29 – Jul 20 |
| Cabbage | Mar 7 – Mar 21 | Apr 11 – Apr 25 | — | Jun 29 – Jul 20 |
| Cauliflower | Mar 7 – Mar 21 | Apr 18 – May 2 | — | Jun 29 – Jul 20 |
| Okra | Mar 21 – Apr 4 | May 23 – Jun 6 | May 23 – Jun 6 | — |
| Basil | Mar 21 – Apr 4 | May 9 – May 23 | — | — |
| Peas | — | — | Mar 21 – Apr 11 | Jul 13 – Aug 3 |
| Spinach | — | — | Mar 21 – Apr 11 | Aug 10 – Aug 31 |
| Radishes | — | — | Mar 28 – May 9 | Aug 24 – Sep 14 |
| Cucumbers | Apr 4 – Apr 11 | May 16 – May 23 | May 9 – May 23 | Jul 20 – Aug 3 |
| Zucchini & Summer Squash | Apr 4 – Apr 11 | — | May 9 – May 23 | Jul 27 – Aug 10 |
| Winter Squash & Pumpkins | Apr 4 – Apr 11 | — | May 9 – May 23 | — |
| Melons & Watermelon | Apr 4 – Apr 11 | May 16 – May 30 | — | — |
| Carrots | — | — | Apr 11 – May 9 | Jul 13 – Jul 27 |
| Beets | — | — | Apr 11 – May 9 | Jul 27 – Aug 10 |
| Potatoes | — | — | Apr 11 – May 2 | — |
| Swiss Chard | — | — | Apr 18 – May 16 | Jul 27 – Aug 10 |
| Cilantro | — | — | Apr 18 – May 9 | Aug 10 – Aug 31 |
| Green Beans | — | — | May 9 – May 30 | Jul 20 – Aug 3 |
| Sweet Corn | — | — | May 9 – May 23 | — |
| Sweet Potatoes | — | May 16 – Jun 6 | — | — |
| Garlic | — | — | — | Sep 21 – Oct 26 |
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 New Hampton, IA weather station, 27 km away (elevation 1,148 ft (350 m)).
Frost dates near Elma
- Alta Vista May 2 · Oct 5
- Riceville Apr 30 · Oct 9
- North Washington May 2 · Oct 5
- Colwell Apr 30 · Oct 6
- Chester May 8 · Oct 1
- Lime Springs May 8 · Oct 1
- Cresco May 8 · Oct 1
- Mc Intire Apr 30 · Oct 9
- Protivin May 8 · Oct 1
- New Hampton May 2 · Oct 5
Frequently asked questions
When is the last frost in Elma, IA?
The median last spring frost in Elma, IA is May 2. There is still about a 10% chance of frost after May 14, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Elma, IA?
The median first fall frost is October 5, with about a 10% chance of frost before September 23.
How long is the growing season in Elma, IA?
About 156 days between the median last spring frost and first fall frost.
What planting zone is Elma, IA?
Elma, IA is in USDA hardiness zone 4b.