Frost dates · USDA zone 5b
Frost dates for Council Bluffs, IA
Council Bluffs, IA sees its last 32 °F night of spring around April 18 and its first of fall around October 21 — a 185-day freeze-free season in a typical year.
Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.
Freeze odds, by date
| Odds | Last spring freeze after | First fall freeze before |
|---|---|---|
| 9 years in 10 | Apr 5 | Nov 1 |
| Median — 1 year in 2 | Apr 18 | Oct 21 |
| 1 year in 10 | Apr 30 | Oct 6 |
The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 185 days median, at least 163 in 9 years of 10, at least 204 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of Apr 8 and first of Oct 30.
Council Bluffs planting calendar, 2027
Every row runs from the median last frost (Apr 18) and median first frost (Oct 21) above, using each cultivar's days to maturity. Same engine as the Plan Builder.
| Crop | Start indoors | Transplant / plant | First harvest | Days |
|---|---|---|---|---|
| Hardneck GarlicSiberian (porcelain hardneck) | — | Oct 15prior fall | Jun 12 | 240 from sow |
| Spanish OnionYellow Sweet Spanish (long-day) | Jan 24 | Mar 21 | Jul 9 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | Apr 18 | May 18 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Apr 4 | Apr 4 | May 19 | 45 from sow |
| Genovese BasilGenovese | Mar 21 | May 2 | Jul 1 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Feb 21 | Apr 25 | Jul 9 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Feb 7 | May 2 | Aug 5 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Feb 21 | Apr 25 | Jul 9 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Feb 21 | Apr 25 | Jul 14 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Feb 21 | Apr 25 | Jul 14 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Apr 4 | Apr 4 | Jun 13 | 70 from sow |
| TomatilloToma Verde | Mar 7 | Apr 25 | Jul 4 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Mar 7 | Apr 25 | Jul 9 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Mar 7 | Apr 25 | Jul 14 | 80 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.
What sauce can Council Bluffs grow?
Each sauce, scheduled for a Council Bluffs container garden: when the first seeds go in and when enough fruit has ripened for one batch.
Council Bluffs frost questions
When is the last frost in Council Bluffs, IA?
The median last 32 °F freeze at OMAHA EPPLEY AIRFIELD, NE is April 18: half of years see a later one. One year in ten, a freeze still comes after April 30; nine years in ten, it comes after April 5. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in Council Bluffs, IA?
The median first 32 °F freeze of fall is October 21. One year in ten it arrives before October 6; nine years in ten, before November 1.
How long is the growing season in Council Bluffs, IA?
185 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 163 days; one year in ten, at least 204 days.
What growing zone is Council Bluffs, IA?
USDA hardiness zone 5b, per the 2023 USDA Plant Hardiness Zone Map for ZIP 51501. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.
When should I plant tomatoes in Council Bluffs, IA?
Start Roma VF (determinate paste) seeds indoors around Mar 7 and transplant around Apr 25, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Apr 30. First ripe fruit lands around Jul 9.
When should I plant peppers in Council Bluffs, IA?
Sow jalapeño indoors on a heat mat around Feb 21; transplant no earlier than Apr 25, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Jul 9.
Nearby in Iowa
- Sioux Citylast frost Apr 29
- West Des Moineslast frost Apr 18
- Urbandalelast frost Apr 18
- Des Moineslast frost Apr 18
- Ankenylast frost Apr 23
- Ameslast frost Apr 26
All Iowa frost dates → · How frost-date math drives a sowing calendar →