Iowa Planting Guide & Growing Season
Iowa is in USDA hardiness zone 4b-5b with a growing season of 160 days. The average last spring frost is Apr 25 and the average first fall frost is Oct 5. Climate data based on Des Moines.
Growing Conditions in Iowa
How Iowa Compares
Compare Iowa's growing conditions with states that have similar climates.
| State | USDA Zone | Last Frost | First Frost | Season (days) |
|---|---|---|---|---|
| Iowa (IA) | 4b-5b | Apr 25 | Oct 5 | 160 |
| Alabama (AL) | 7a-8b | Mar 15 | Nov 5 | 235 |
| Alaska (AK) | 1a-7b | May 30 | Sep 5 | 100 |
| Arizona (AZ) | 4b-10b | Mar 1 | Nov 15 | 260 |
| Arkansas (AR) | 6b-8a | Apr 1 | Oct 25 | 210 |
| California (CA) | 4b-11a | Feb 15 | Nov 30 | 290 |
Frequently Asked Questions About Gardening in Iowa
When should I start seeds indoors in Iowa?
In Iowa, the average last frost date is Apr 25. Start most seeds indoors 6-8 weeks before this date. The USDA hardiness zone for Iowa is 4b-5b, with a growing season of approximately 160 days.
What USDA hardiness zone is Iowa?
Iowa falls in USDA hardiness zones 4b-5b. This affects which perennial plants will survive winter and influences optimal planting times.
When is the first frost in Iowa?
The average first frost date in Iowa is Oct 5. Plan to harvest cold-sensitive crops before this date or protect them with row covers.
How long is the growing season in Iowa?
Iowa has an average growing season of 160 days, from the last frost (Apr 25) to first frost (Oct 5). This moderate season works well for most common vegetables.
Plan Your Garden
Use our seed starting calculator to get personalized planting dates, or browse all states.