Frost dates for Bloomfield, IA
At Bloomfield, the median last spring frost (32°F) is Apr 16 and the median first fall frost is Oct 22, for a typical growing season of 188 days. For a 90% chance that the last frost has passed, wait until Apr 30. Nearby ZIP codes are in USDA hardiness zone 5b.
- Apr 16Last spring frost (median)50% chance of 32°F after this date
- Apr 30Safer planting date10% chance of 32°F after this date
- Oct 22First fall frost (median)50% chance of 32°F by this date
- 188 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | Apr 13 | Apr 28 | May 10 |
| 32°F | Apr 1 | Apr 16 | Apr 30 |
| 28°F | Mar 22 | Apr 6 | Apr 20 |
| 24°F | Mar 11 | Mar 29 | Apr 11 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Sep 26 | Oct 11 | Oct 24 |
| 32°F | Oct 5 | Oct 22 | Nov 2 |
| 28°F | Oct 19 | Oct 31 | Nov 12 |
| 24°F | Oct 29 | Nov 8 | Nov 25 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 147 days | 167 days | 186 days |
| 32°F | 166 days | 188 days | 207 days |
| 28°F | 190 days | 208 days | 227 days |
| 24°F | 206 days | 226 days | 248 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 52537 | 5b | -15 to -10°F | 0 km |
| 52552 | 5b | -15 to -10°F | 15 km |
| 52584 | 5b | -15 to -10°F | 17 km |
| 52560 | 5b | -15 to -10°F | 19 km |
| 63548 | 5b | -15 to -10°F | 23 km |
| 52554 | 5b | -15 to -10°F | 26 km |
| 63541 | 5b | -15 to -10°F | 32 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USC00130753, at 40.7392, -92.4142, elevation 262 m (858 ft).
- Data quality: Standard (24+ years of data), 26 years of freeze data.
- Average days per year at or below 32°F: 128.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Keosauqua (37 km)
- Centerville (40 km)
- Ottumwa Industrial Airport (41 km)
- Rathbun Dam (41 km)
- Albia 3 NNE (48 km)
- Fairfield (50 km)
- Oskaloosa (68 km)
- Sigourney (68 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.