FrostDateByZip

Frost dates for 61433Fiatt, IL

The average last spring frost in Fiatt is April 17 and the average first fall frost is October 22, giving a typical growing season of about 185 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Apr 17

Safer after May 2 (1-in-10 risk)

Average first fall frost
Oct 22

Possible by Oct 7 (1-in-10 risk)

Growing season
185 days

Last frost typically in 169 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 15 · Apr 28 · May 12Sep 29 · Oct 12 · Oct 24165 days100%
Frost / freeze (32°F)Apr 4 · Apr 17 · May 2Oct 7 · Oct 22 · Nov 1185 days100%
Hard freeze (28°F)Mar 22 · Apr 7 · Apr 21Oct 18 · Oct 30 · Nov 13204 days100%

Planting calendar for Fiatt

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 17 – May 23
TomatoesTransplant outdoorsMay 3 – Jul 2
PeppersStart seeds indoorsMar 17 – Apr 17
PeppersTransplant outdoorsMay 17 – Jun 17
EggplantStart seeds indoorsApr 3 – May 2
EggplantTransplant outdoorsMay 17 – Jun 17
CucumbersSow outdoorsMay 17 – Jul 12
Summer squashSow outdoorsMay 3 – Jun 17
Winter squash & pumpkinsSow outdoorsMay 17 – Jun 17
Snap beansSow outdoorsMay 3 – Aug 4
Sweet cornSow outdoorsMay 3 – Jul 2
Watermelon & cantaloupeSow outdoorsMay 17 – Jun 17
OkraSow outdoorsMay 10 – Jun 2
PeasSow outdoors (spring)Mar 17 – May 2
PotatoesPlant outdoors (spring)Mar 17 – May 17
OnionsStart seeds indoors (spring)Feb 3 – Mar 2
OnionsTransplant outdoors (spring)Apr 3 – May 2
BroccoliStart seeds indoors (spring)Feb 27 – Apr 2
BroccoliTransplant outdoors (spring)Apr 3 – May 2
BroccoliStart seeds indoors (fall)Jun 22 – Jul 2
BroccoliTransplant outdoors (fall)Jul 22 – Aug 2
CabbageStart seeds indoors (spring)Feb 17 – Mar 17
CabbageTransplant outdoors (spring)Mar 17 – Apr 17
CabbageStart seeds indoors (fall)Jun 12 – Jul 12
CabbageTransplant outdoors (fall)Jul 12 – Aug 12
Leaf lettuceSow outdoors (spring)Mar 17 – Jun 2
Leaf lettuceSow outdoors (fall)Jul 12 – Aug 28
SpinachSow outdoors (spring)Mar 10 – Apr 23
SpinachSow outdoors (fall)Jul 29 – Sep 2
RadishesSow outdoors (spring)Mar 17 – May 7
RadishesSow outdoors (fall)Jul 12 – Sep 12
KaleSow outdoors (spring)Apr 3 – Apr 23
KaleSow outdoors (fall)Jul 5 – Aug 12
CarrotsSow outdoors (spring)Apr 17 – Jun 2
CarrotsSow outdoors (fall)Jun 12 – Jul 28
GarlicPlant outdoors (fall)Oct 12 – Nov 12

Where these dates come from

ZIP code 61433 is matched to the NOAA station Prairie City 2S, IL, 24.3 km away, at 650 ft elevation (26 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Prairie City 2S, IL (used)650 ftApr 17Oct 22
Avon, IL640 ftApr 22Oct 19
Havana, IL463 ftApr 17Oct 19
Knoxville, IL728 ftApr 21Oct 20

Frost dates near Fiatt

Frequently asked questions

When is the last frost in Fiatt, IL?
For ZIP code 61433, the average last spring frost (32°F) is April 17, based on NOAA 1991-2020 climate normals for the Prairie City 2S, IL weather station. There is a 1-in-10 chance of a frost after May 2.
When is the first frost in Fiatt, IL?
The average first fall frost (32°F) is October 22. There is a 1-in-10 chance of frost by October 7, so tender plants are at risk from that point on.
How long is the growing season in 61433?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 185 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.