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Frost Dates for Bettendorf, IA

Last spring frost
Apr 16
First fall frost
Oct 25
Growing season
190 days
Hardiness zone
5b

In an average year around Bettendorf, IA, the last spring frost (32°F) is about Apr 16 and the first fall frost is about Oct 25, giving roughly a 190-day growing season. To be safe most years, wait until Apr 2 before setting out tender plants.

Last spring frost

Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.

Last spring frost - Bettendorf, IA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 8 Apr 27 Apr 11
Freeze (32°F) Apr 30 Apr 16 Apr 2
Hard (28°F) Apr 21 Apr 6 Mar 21
Severe (24°F) Apr 9 Mar 27 Mar 10
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 8 May 5 May 2 Apr 30 Apr 27 Apr 23 Apr 20 Apr 17 Apr 11
32°F Apr 30 Apr 25 Apr 22 Apr 18 Apr 16 Apr 13 Apr 9 Apr 6 Apr 2
28°F Apr 21 Apr 15 Apr 11 Apr 8 Apr 6 Apr 3 Apr 1 Mar 27 Mar 21
24°F Apr 9 Apr 5 Apr 2 Mar 31 Mar 27 Mar 23 Mar 19 Mar 15 Mar 10
20°F Apr 2 Mar 29 Mar 24 Mar 21 Mar 17 Mar 14 Mar 11 Mar 7 Mar 3
16°F Mar 26 Mar 20 Mar 15 Mar 13 Mar 10 Mar 7 Mar 4 Mar 1 Feb 24

First fall frost

Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.

First fall frost - Bettendorf, IA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Oct 1 Oct 15 Oct 28
Freeze (32°F) Oct 11 Oct 25 Nov 6
Hard (28°F) Oct 23 Nov 2 Nov 18
Severe (24°F) Nov 1 Nov 13 Nov 29
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Oct 1 Oct 6 Oct 10 Oct 12 Oct 15 Oct 18 Oct 20 Oct 24 Oct 28
32°F Oct 11 Oct 16 Oct 20 Oct 22 Oct 25 Oct 28 Oct 30 Nov 1 Nov 6
28°F Oct 23 Oct 27 Oct 30 Nov 1 Nov 2 Nov 5 Nov 8 Nov 13 Nov 18
24°F Nov 1 Nov 4 Nov 7 Nov 10 Nov 13 Nov 16 Nov 19 Nov 23 Nov 29
20°F Nov 7 Nov 12 Nov 16 Nov 19 Nov 22 Nov 26 Nov 30 Dec 2 Dec 8
16°F Nov 13 Nov 18 Nov 23 Nov 27 Dec 1 Dec 2 Dec 6 Dec 9 Dec 16

Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.

Where this data comes from

These dates are computed from the nearest official weather station with long-term records: Le Claire L&D 14, Ia, about 3.6 miles away@if(!empty($station['elevation_ft'])), at 577 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

@endif
How we calculate these dates

Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.

Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.

Frequently asked questions

When is the last frost in Bettendorf, IA?

On average, the last spring frost (32°F) around Bettendorf, IA is about Apr 16. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 2.

When is the first frost in the fall?

The first fall frost around Bettendorf, IA typically arrives about Oct 25. Count back by a crop's days to maturity to find the latest date you can plant it.

When can I plant tomatoes and other tender crops?

Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 16 on average, or Apr 2 to be safe most years.

How long is the growing season here?

The frost-free growing season (between the last spring and first fall 32°F frost) is about 190 days in a typical year.

Are these dates a forecast for this year?

No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.

Local weather for 52722 Planting calendar → Iowa frost dates →

Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026