FrostDateByZip

Frost dates for 52075Springbrook, IA

The average last spring frost in Springbrook is April 25 and the average first fall frost is October 16, giving a typical growing season of about 172 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Apr 25

Safer after May 11 (1-in-10 risk)

Average first fall frost
Oct 16

Possible by Oct 1 (1-in-10 risk)

Growing season
172 days

Last frost typically in 176 days

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
TemperatureLast spring: 90% / 50% / 10% chanceFirst fall: 10% / 50% / 90% chanceGrowing season (50%)Years with at least one
Light frost (36°F)Apr 21 · May 5 · May 20Sep 23 · Oct 5 · Oct 19152 days100%
Frost / freeze (32°F)Apr 10 · Apr 25 · May 11Oct 1 · Oct 16 · Oct 29172 days100%
Hard freeze (28°F)Apr 1 · Apr 13 · May 2Oct 13 · Oct 27 · Nov 8195 days100%

Planting calendar for Springbrook

Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.

CropTaskWindow
TomatoesStart seeds indoorsMar 25 – May 31
TomatoesTransplant outdoorsMay 11 – Jun 26
PeppersStart seeds indoorsMar 25 – Apr 25
PeppersTransplant outdoorsMay 25 – Jun 25
EggplantStart seeds indoorsApr 11 – May 10
EggplantTransplant outdoorsMay 25 – Jun 25
CucumbersSow outdoorsMay 25 – Jul 6
Summer squashSow outdoorsMay 11 – Jun 25
Winter squash & pumpkinsSow outdoorsMay 25 – Jun 25
Snap beansSow outdoorsMay 11 – Jul 29
Sweet cornSow outdoorsMay 11 – Jun 26
Watermelon & cantaloupeSow outdoorsMay 25 – Jun 25
OkraSow outdoorsMay 18 – Jun 10
PeasSow outdoors (spring)Mar 25 – May 10
PotatoesPlant outdoors (spring)Mar 25 – May 25
OnionsStart seeds indoors (spring)Feb 11 – Mar 10
OnionsTransplant outdoors (spring)Apr 11 – May 10
BroccoliStart seeds indoors (spring)Mar 7 – Apr 10
BroccoliTransplant outdoors (spring)Apr 11 – May 10
BroccoliStart seeds indoors (fall)Jun 16 – Jun 26
BroccoliTransplant outdoors (fall)Jul 16 – Jul 27
CabbageStart seeds indoors (spring)Feb 25 – Mar 25
CabbageTransplant outdoors (spring)Mar 25 – Apr 25
CabbageStart seeds indoors (fall)Jun 6 – Jul 6
CabbageTransplant outdoors (fall)Jul 6 – Aug 6
Leaf lettuceSow outdoors (spring)Mar 25 – Jun 10
Leaf lettuceSow outdoors (fall)Jul 6 – Aug 22
SpinachSow outdoors (spring)Mar 18 – May 1
SpinachSow outdoors (fall)Jul 23 – Aug 27
RadishesSow outdoors (spring)Mar 25 – May 15
RadishesSow outdoors (fall)Jul 6 – Sep 6
KaleSow outdoors (spring)Apr 11 – May 1
KaleSow outdoors (fall)Jun 29 – Aug 6
CarrotsSow outdoors (spring)Apr 25 – Jun 10
CarrotsSow outdoors (fall)Jun 6 – Jul 22
GarlicPlant outdoors (fall)Oct 6 – Nov 6

Where these dates come from

ZIP code 52075 is matched to the NOAA station Bellevue L&D 12, IA, 11.6 km away, at 603 ft elevation (204 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Bellevue L&D 12, IA (used)603 ftApr 25Oct 16
Maquoketa, IA668 ftApr 25Oct 14
Elizabeth, IL675 ftMay 1Oct 9
Galena, IL822 ftApr 26Oct 15

Frost dates near Springbrook

Frequently asked questions

When is the last frost in Springbrook, IA?
For ZIP code 52075, the average last spring frost (32°F) is April 25, based on NOAA 1991-2020 climate normals for the Bellevue L&D 12, IA weather station. There is a 1-in-10 chance of a frost after May 11.
When is the first frost in Springbrook, IA?
The average first fall frost (32°F) is October 16. There is a 1-in-10 chance of frost by October 1, so tender plants are at risk from that point on.
How long is the growing season in 52075?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 172 days long.
Are these frost dates a forecast?
No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.