FrostDateByZip

Frost dates for 62236Columbia, IL

The average last spring frost in Columbia is April 6 and the average first fall frost is October 27, giving a typical growing season of about 203 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Apr 6

Safer after Apr 20 (1-in-10 risk)

Average first fall frost
Oct 27

Possible by Oct 14 (1-in-10 risk)

Growing season
203 days

Last frost typically in 155 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 4 · Apr 18 · May 3Oct 5 · Oct 18 · Oct 28181 days100%
Frost / freeze (32°F)Mar 22 · Apr 6 · Apr 20Oct 14 · Oct 27 · Nov 7203 days100%
Hard freeze (28°F)Mar 11 · Mar 27 · Apr 10Oct 25 · Nov 5 · Nov 23225 days100%

Planting calendar for Columbia

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 6 – May 12
TomatoesTransplant outdoorsApr 22 – Jul 7
PeppersStart seeds indoorsMar 6 – Apr 6
PeppersTransplant outdoorsMay 6 – Jun 6
EggplantStart seeds indoorsMar 23 – Apr 21
EggplantTransplant outdoorsMay 6 – Jun 6
CucumbersSow outdoorsMay 6 – Jul 17
Summer squashSow outdoorsApr 22 – Jun 6
Winter squash & pumpkinsSow outdoorsMay 6 – Jun 6
Snap beansSow outdoorsApr 22 – Aug 9
Sweet cornSow outdoorsApr 22 – Jul 7
Watermelon & cantaloupeSow outdoorsMay 6 – Jun 6
OkraSow outdoorsApr 29 – May 22
PeasSow outdoors (spring)Mar 6 – Apr 21
PotatoesPlant outdoors (spring)Mar 6 – May 6
OnionsStart seeds indoors (spring)Jan 23 – Feb 19
OnionsTransplant outdoors (spring)Mar 23 – Apr 21
BroccoliStart seeds indoors (spring)Feb 16 – Mar 22
BroccoliTransplant outdoors (spring)Mar 23 – Apr 21
BroccoliStart seeds indoors (fall)Jun 27 – Jul 7
BroccoliTransplant outdoors (fall)Jul 27 – Aug 7
CabbageStart seeds indoors (spring)Feb 6 – Mar 6
CabbageTransplant outdoors (spring)Mar 6 – Apr 6
CabbageStart seeds indoors (fall)Jun 17 – Jul 17
CabbageTransplant outdoors (fall)Jul 17 – Aug 17
Leaf lettuceSow outdoors (spring)Mar 6 – May 22
Leaf lettuceSow outdoors (fall)Jul 17 – Sep 2
SpinachSow outdoors (spring)Feb 27 – Apr 12
SpinachSow outdoors (fall)Aug 3 – Sep 7
RadishesSow outdoors (spring)Mar 6 – Apr 26
RadishesSow outdoors (fall)Jul 17 – Sep 17
KaleSow outdoors (spring)Mar 23 – Apr 12
KaleSow outdoors (fall)Jul 10 – Aug 17
CarrotsSow outdoors (spring)Apr 6 – May 22
CarrotsSow outdoors (fall)Jun 17 – Aug 2
GarlicPlant outdoors (fall)Oct 17 – Nov 17

Where these dates come from

ZIP code 62236 is matched to the NOAA station Cahokia, IL, 15 km away, at 400 ft elevation (105 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Cahokia, IL (used)400 ftApr 6Oct 27
Cahokia St Louis Ap, IL413 ftApr 8Oct 26
St Louis Sci Ctr, MO515 ftApr 1Nov 4
Festus, MO600 ftApr 9Oct 26

Frost dates near Columbia

Frequently asked questions

When is the last frost in Columbia, IL?
For ZIP code 62236, the average last spring frost (32°F) is April 6, based on NOAA 1991-2020 climate normals for the Cahokia, IL weather station. There is a 1-in-10 chance of a frost after April 20.
When is the first frost in Columbia, IL?
The average first fall frost (32°F) is October 27. There is a 1-in-10 chance of frost by October 14, so tender plants are at risk from that point on.
How long is the growing season in 62236?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 203 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.