Frost Dates for Denison, IA

Frost Dates

Last Spring Frost (50%) iA 50% chance that the last spring frost has already passed by this date. Most gardeners use this as their primary planting guide. April 27
First Fall Frost (50%) iA 50% chance that the first fall frost has occurred by this date. Plan to harvest or protect tender plants before this date. October 11
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

30% Probability iOnly a 30% chance of frost remaining by this date. Use these dates for a safer planting window, especially for tender plants sensitive to cold.

Last Spring Frost May 2
First Fall Frost October 4

Hard Freeze (28°F / -2°C)

Last Spring Hard Freeze April 17
First Fall Hard Freeze October 22
42.04°N, -95.33°W © OpenStreetMap

Growing Season

167 Days April 27 to October 11

USDA Hardiness Zone iHardiness zones indicate which perennial plants can survive winter in your area. For annual vegetables, frost dates and growing season length matter more than hardiness zone.

Zone 5b

Learn more

Temperature

0° 30° 60° 90°
19°
High: 27°
Avg: 19°
Low: 10°
Jan
23°
High: 32°
Avg: 23°
Low: 14°
Feb
35°
High: 45°
Avg: 35°
Low: 25°
Mar
47°
High: 58°
Avg: 47°
Low: 36°
Apr
59°
High: 70°
Avg: 59°
Low: 49°
May
69°
High: 80°
Avg: 69°
Low: 59°
Jun
73°
High: 83°
Avg: 73°
Low: 63°
Jul
71°
High: 81°
Avg: 71°
Low: 61°
Aug
63°
High: 75°
Avg: 63°
Low: 52°
Sep
50°
High: 62°
Avg: 50°
Low: 39°
Oct
36°
High: 46°
Avg: 36°
Low: 26°
Nov
24°
High: 32°
Avg: 24°
Low: 16°
Dec
32°F
28°F
Avg High Avg Temp Avg Low Light Frost (32°F) Hard Frost (28°F)

Precipitation

0" 2" 4" 6" 6.2"
2.4"
2.38"
Jan
2.3"
2.26"
Feb
3.8"
3.75"
Mar
5.5"
5.47"
Apr
6.2"
6.20"
May
6.1"
6.12"
Jun
5.2"
5.17"
Jul
5.7"
5.68"
Aug
5.8"
5.75"
Sep
4.4"
4.44"
Oct
3.0"
3.02"
Nov
2.6"
2.60"
Dec

Sunrise / Sunset

4a7a10a1p4p7p10pNoonJanFebMarAprMayJunJulAugSepOctNovDec9h10h12h13h14h15h15h14h12h11h10h9h
Jan: 7:22 AM – 4:38 PM · 9h 16m
Feb: 6:49 AM – 5:11 PM · 10h 22m
Mar: 6:10 AM – 5:50 PM · 11h 40m
Apr: 5:26 AM – 6:34 PM · 13h 09m
May: 4:49 AM – 7:11 PM · 14h 23m
Jun: 4:29 AM – 7:31 PM · 15h 03m
Jul: 4:37 AM – 7:23 PM · 14h 47m
Aug: 5:09 AM – 6:51 PM · 13h 42m
Sep: 5:52 AM – 6:08 PM · 12h 16m
Oct: 6:35 AM – 5:25 PM · 10h 50m
Nov: 7:13 AM – 4:47 PM · 9h 34m
Dec: 7:32 AM – 4:28 PM · 8h 57m
Daylight Longest: 15h 04m · Shortest: 8h 56m

Nearby Stations

Carroll, IAApril 27 - October 10 Mapleton No.2, IA May 3 - October 1 Castana Exp Farm, IA April 25 - October 12 Battle Creek 3ne, IA May 1 - October 1 Ida Grove 5nw, IA April 27 - October 12 Harlan, IAApril 27 - October 9

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