FrostDateByZip

Frost dates for 50607Aurora, IA

The average last spring frost in Aurora is April 30 and the average first fall frost is October 7, giving a typical growing season of about 159 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Apr 30

Safer after May 12 (1-in-10 risk)

Average first fall frost
Oct 7

Possible by Sep 23 (1-in-10 risk)

Growing season
159 days

Last frost typically in 179 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 26 · May 9 · May 22Sep 15 · Sep 29 · Oct 12142 days100%
Frost / freeze (32°F)Apr 16 · Apr 30 · May 12Sep 23 · Oct 7 · Oct 21159 days100%
Hard freeze (28°F)Apr 5 · Apr 20 · May 4Oct 2 · Oct 17 · Oct 31179 days100%

Planting calendar for Aurora

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 30 – Jun 5
TomatoesTransplant outdoorsMay 16 – Jun 17
PeppersStart seeds indoorsMar 30 – Apr 30
PeppersTransplant outdoorsMay 30 – Jun 30
EggplantStart seeds indoorsApr 16 – May 15
EggplantTransplant outdoorsMay 30 – Jun 30
CucumbersSow outdoorsMay 30 – Jun 27
Summer squashSow outdoorsMay 16 – Jun 30
Winter squash & pumpkinsSow outdoorsMay 30 – Jun 30
Snap beansSow outdoorsMay 16 – Jul 20
Sweet cornSow outdoorsMay 16 – Jun 17
Watermelon & cantaloupeSow outdoorsMay 30 – Jun 30
OkraSow outdoorsMay 23 – Jun 15
PeasSow outdoors (spring)Mar 30 – May 15
PotatoesPlant outdoors (spring)Mar 30 – May 30
OnionsStart seeds indoors (spring)Feb 16 – Mar 15
OnionsTransplant outdoors (spring)Apr 16 – May 15
BroccoliStart seeds indoors (spring)Mar 12 – Apr 15
BroccoliTransplant outdoors (spring)Apr 16 – May 15
BroccoliStart seeds indoors (fall)Jun 7 – Jun 17
BroccoliTransplant outdoors (fall)Jul 7 – Jul 18
CabbageStart seeds indoors (spring)Mar 2 – Mar 30
CabbageTransplant outdoors (spring)Mar 30 – Apr 30
CabbageStart seeds indoors (fall)May 28 – Jun 27
CabbageTransplant outdoors (fall)Jun 27 – Jul 28
Leaf lettuceSow outdoors (spring)Mar 30 – Jun 15
Leaf lettuceSow outdoors (fall)Jun 27 – Aug 13
SpinachSow outdoors (spring)Mar 23 – May 6
SpinachSow outdoors (fall)Jul 14 – Aug 18
RadishesSow outdoors (spring)Mar 30 – May 20
RadishesSow outdoors (fall)Jun 27 – Aug 28
KaleSow outdoors (spring)Apr 16 – May 6
KaleSow outdoors (fall)Jun 20 – Jul 28
CarrotsSow outdoors (spring)Apr 30 – Jun 15
CarrotsSow outdoors (fall)May 28 – Jul 13
GarlicPlant outdoors (fall)Sep 27 – Oct 28

Where these dates come from

ZIP code 50607 is matched to the NOAA station Independence #1, IA, 15.7 km away, at 1,010 ft elevation (115 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Independence #1, IA (used)1,010 ftApr 30Oct 7
Stanley, IA1,114 ftMay 4Oct 1
Oelwein 1E, IA1,165 ftApr 27Oct 13
Oelwein 2 S, IA1,010 ftApr 30Oct 9

Frost dates near Aurora

Frequently asked questions

When is the last frost in Aurora, IA?
For ZIP code 50607, the average last spring frost (32°F) is April 30, based on NOAA 1991-2020 climate normals for the Independence #1, IA weather station. There is a 1-in-10 chance of a frost after May 12.
When is the first frost in Aurora, IA?
The average first fall frost (32°F) is October 7. There is a 1-in-10 chance of frost by September 23, so tender plants are at risk from that point on.
How long is the growing season in 50607?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 159 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.