FrostDateByZip

Frost dates for 61236Barstow, IL

The average last spring frost in Barstow is April 16 and the average first fall frost is October 25, giving a typical growing season of about 190 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Apr 16

Safer after Apr 30 (1-in-10 risk)

Average first fall frost
Oct 25

Possible by Oct 11 (1-in-10 risk)

Growing season
190 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 11 · Apr 27 · May 8Oct 1 · Oct 15 · Oct 28171 days100%
Frost / freeze (32°F)Apr 2 · Apr 16 · Apr 30Oct 11 · Oct 25 · Nov 6190 days100%
Hard freeze (28°F)Mar 21 · Apr 6 · Apr 21Oct 23 · Nov 2 · Nov 18210 days100%

Planting calendar for Barstow

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 16 – May 22
TomatoesTransplant outdoorsMay 2 – Jul 5
PeppersStart seeds indoorsMar 16 – Apr 16
PeppersTransplant outdoorsMay 16 – Jun 16
EggplantStart seeds indoorsApr 2 – May 1
EggplantTransplant outdoorsMay 16 – Jun 16
CucumbersSow outdoorsMay 16 – Jul 15
Summer squashSow outdoorsMay 2 – Jun 16
Winter squash & pumpkinsSow outdoorsMay 16 – Jun 16
Snap beansSow outdoorsMay 2 – Aug 7
Sweet cornSow outdoorsMay 2 – Jul 5
Watermelon & cantaloupeSow outdoorsMay 16 – Jun 16
OkraSow outdoorsMay 9 – Jun 1
PeasSow outdoors (spring)Mar 16 – May 1
PotatoesPlant outdoors (spring)Mar 16 – May 16
OnionsStart seeds indoors (spring)Feb 2 – Mar 1
OnionsTransplant outdoors (spring)Apr 2 – May 1
BroccoliStart seeds indoors (spring)Feb 26 – Apr 1
BroccoliTransplant outdoors (spring)Apr 2 – May 1
BroccoliStart seeds indoors (fall)Jun 25 – Jul 5
BroccoliTransplant outdoors (fall)Jul 25 – Aug 5
CabbageStart seeds indoors (spring)Feb 16 – Mar 16
CabbageTransplant outdoors (spring)Mar 16 – Apr 16
CabbageStart seeds indoors (fall)Jun 15 – Jul 15
CabbageTransplant outdoors (fall)Jul 15 – Aug 15
Leaf lettuceSow outdoors (spring)Mar 16 – Jun 1
Leaf lettuceSow outdoors (fall)Jul 15 – Aug 31
SpinachSow outdoors (spring)Mar 9 – Apr 22
SpinachSow outdoors (fall)Aug 1 – Sep 5
RadishesSow outdoors (spring)Mar 16 – May 6
RadishesSow outdoors (fall)Jul 15 – Sep 15
KaleSow outdoors (spring)Apr 2 – Apr 22
KaleSow outdoors (fall)Jul 8 – Aug 15
CarrotsSow outdoors (spring)Apr 16 – Jun 1
CarrotsSow outdoors (fall)Jun 15 – Jul 31
GarlicPlant outdoors (fall)Oct 15 – Nov 15

Where these dates come from

ZIP code 61236 is matched to the NOAA station Le Claire L&D 14, IA, 7.6 km away, at 577 ft elevation (6 ft higher than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Le Claire L&D 14, IA (used)577 ftApr 16Oct 25
Moline Quad City Intl Ap, IL592 ftApr 24Oct 18
Rock Island L&D 15, IL568 ftApr 19Oct 22
Geneseo, IL639 ftApr 20Oct 20

Frost dates near Barstow

Frequently asked questions

When is the last frost in Barstow, IL?
For ZIP code 61236, the average last spring frost (32°F) is April 16, based on NOAA 1991-2020 climate normals for the Le Claire L&D 14, IA weather station. There is a 1-in-10 chance of a frost after April 30.
When is the first frost in Barstow, IL?
The average first fall frost (32°F) is October 25. There is a 1-in-10 chance of frost by October 11, so tender plants are at risk from that point on.
How long is the growing season in 61236?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 190 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.