Hull, IA frost dates
How Hull compares
- In 8 years out of 10, the last spring frost in Hull falls between April 17 and May 12, a 25-day window. The first fall frost falls between September 19 and October 18.
- The median last frost is 2 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 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 Sioux Falls, SD, 66 km away, the last frost here is 4 days later than there and the growing season is 14 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 17 |
| 50% (median) | April 30 |
| 10% (safe for tender plants) | May 12 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 19 |
| 50% (median) | October 3 |
| 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 Hull, IA
Hull, IA frost dates — last frost Apr 30, first frost Oct 3, zone 5a. whenisthelastfrost.com
When to plant vegetables in Hull, 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 8 – Sep 5 |
| Kale | Mar 5 – Mar 19 | Apr 2 – Apr 16 | Apr 2 – Apr 16 | Jul 25 – Aug 15 |
| Broccoli | Mar 5 – Mar 19 | Apr 16 – Apr 30 | — | Jun 27 – Jul 18 |
| Cabbage | Mar 5 – Mar 19 | Apr 9 – Apr 23 | — | Jun 27 – Jul 18 |
| Cauliflower | Mar 5 – Mar 19 | Apr 16 – Apr 30 | — | Jun 27 – Jul 18 |
| 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 11 – Aug 1 |
| Spinach | — | — | Mar 19 – Apr 9 | Aug 8 – Aug 29 |
| Radishes | — | — | Mar 26 – May 7 | Aug 22 – Sep 12 |
| Cucumbers | Apr 2 – Apr 9 | May 14 – May 21 | May 7 – May 21 | Jul 18 – Aug 1 |
| Zucchini & Summer Squash | Apr 2 – Apr 9 | — | May 7 – May 21 | Jul 25 – Aug 8 |
| 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 11 – Jul 25 |
| Beets | — | — | Apr 9 – May 7 | Jul 25 – Aug 8 |
| Potatoes | — | — | Apr 9 – Apr 30 | — |
| Swiss Chard | — | — | Apr 16 – May 14 | Jul 25 – Aug 8 |
| Cilantro | — | — | Apr 16 – May 7 | Aug 8 – Aug 29 |
| Green Beans | — | — | May 7 – May 28 | Jul 18 – Aug 1 |
| Sweet Corn | — | — | May 7 – May 21 | — |
| Sweet Potatoes | — | May 14 – Jun 4 | — | — |
| Garlic | — | — | — | Sep 19 – Oct 24 |
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 Sioux Ctr 2 Se, IA weather station, 16 km away (elevation 1,362 ft (415 m)).
Frost dates near Hull
- Doon May 1 · Oct 4
- Boyden May 5 · Sep 28
- Sioux Center Apr 30 · Oct 3
- Rock Valley Apr 30 · Oct 3
- Matlock May 5 · Sep 28
- Alvord May 1 · Oct 4
- George May 1 · Oct 4
- Orange City Apr 30 · Oct 3
- Hospers May 5 · Sep 28
- Sheldon May 5 · Sep 28
Frequently asked questions
When is the last frost in Hull, IA?
The median last spring frost in Hull, IA is April 30. There is still about a 10% chance of frost after May 12, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Hull, IA?
The median first fall frost is October 3, with about a 10% chance of frost before September 19.
How long is the growing season in Hull, IA?
About 156 days between the median last spring frost and first fall frost.
What planting zone is Hull, IA?
Hull, IA is in USDA hardiness zone 5a.