Nashua, IA frost dates
How Nashua compares
- In 8 years out of 10, the last spring frost in Nashua falls between April 15 and May 14, a 29-day window. The first fall frost falls between September 21 and October 19.
- The median last frost is 2 days later than the Iowa median of Apr 28.
- Its 159-day growing season is longer than 24% 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 154 nights a year at or below 32°F.
- Compared with Waterloo, IA, 55 km away, the last frost here is 3 days later than there and the growing season is 7 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 15 |
| 50% (median) | April 30 |
| 10% (safe for tender plants) | May 14 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 21 |
| 50% (median) | October 6 |
| 90% (late) | October 19 |
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 Nashua, IA
Nashua, IA frost dates — last frost Apr 30, first frost Oct 6, zone 5a. whenisthelastfrost.com
When to plant vegetables in Nashua, 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 11 – Sep 8 |
| Kale | Mar 5 – Mar 19 | Apr 2 – Apr 16 | Apr 2 – Apr 16 | Jul 28 – Aug 18 |
| Broccoli | Mar 5 – Mar 19 | Apr 16 – Apr 30 | — | Jun 30 – Jul 21 |
| Cabbage | Mar 5 – Mar 19 | Apr 9 – Apr 23 | — | Jun 30 – Jul 21 |
| Cauliflower | Mar 5 – Mar 19 | Apr 16 – Apr 30 | — | Jun 30 – Jul 21 |
| 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 14 – Aug 4 |
| Spinach | — | — | Mar 19 – Apr 9 | Aug 11 – Sep 1 |
| Radishes | — | — | Mar 26 – May 7 | Aug 25 – Sep 15 |
| Cucumbers | Apr 2 – Apr 9 | May 14 – May 21 | May 7 – May 21 | Jul 21 – Aug 4 |
| Zucchini & Summer Squash | Apr 2 – Apr 9 | — | May 7 – May 21 | Jul 28 – Aug 11 |
| 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 14 – Jul 28 |
| Beets | — | — | Apr 9 – May 7 | Jul 28 – Aug 11 |
| Potatoes | — | — | Apr 9 – Apr 30 | — |
| Swiss Chard | — | — | Apr 16 – May 14 | Jul 28 – Aug 11 |
| Cilantro | — | — | Apr 16 – May 7 | Aug 11 – Sep 1 |
| Green Beans | — | — | May 7 – May 28 | Jul 21 – Aug 4 |
| Sweet Corn | — | — | May 7 – May 21 | — |
| Sweet Potatoes | — | May 14 – Jun 4 | — | — |
| Garlic | — | — | — | Sep 22 – Oct 27 |
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 Charles City, IA weather station, 17 km away (elevation 994 ft (303 m)).
Frost dates near Nashua
- Ionia May 2 · Oct 5
- Plainfield Apr 29 · Oct 9
- Charles City Apr 30 · Oct 6
- Clarksville Apr 27 · Oct 8
- Frederika Apr 29 · Oct 9
- North Washington May 2 · Oct 5
- New Hampton May 2 · Oct 5
- Waverly Apr 29 · Oct 9
- Greene Apr 27 · Oct 8
- Colwell Apr 30 · Oct 6
Frequently asked questions
When is the last frost in Nashua, IA?
The median last spring frost in Nashua, IA is April 30. 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 Nashua, IA?
The median first fall frost is October 6, with about a 10% chance of frost before September 21.
How long is the growing season in Nashua, IA?
About 159 days between the median last spring frost and first fall frost.
What planting zone is Nashua, IA?
Nashua, IA is in USDA hardiness zone 5a.