FrostDateByZip

Frost dates for 52646Oakville, IA

The average last spring frost in Oakville is April 14 and the average first fall frost is October 24, giving a typical growing season of about 190 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Apr 14

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

Average first fall frost
Oct 24

Possible by Oct 9 (1-in-10 risk)

Growing season
190 days

Last frost typically in 165 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 14Sep 30 · Oct 14 · Oct 26168 days100%
Frost / freeze (32°F)Apr 1 · Apr 14 · May 2Oct 9 · Oct 24 · Nov 4190 days100%
Hard freeze (28°F)Mar 18 · Apr 5 · Apr 21Oct 21 · Nov 1 · Nov 17210 days100%

Planting calendar for Oakville

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 14 – May 20
TomatoesTransplant outdoorsApr 30 – Jul 4
PeppersStart seeds indoorsMar 14 – Apr 14
PeppersTransplant outdoorsMay 14 – Jun 14
EggplantStart seeds indoorsMar 31 – Apr 29
EggplantTransplant outdoorsMay 14 – Jun 14
CucumbersSow outdoorsMay 14 – Jul 14
Summer squashSow outdoorsApr 30 – Jun 14
Winter squash & pumpkinsSow outdoorsMay 14 – Jun 14
Snap beansSow outdoorsApr 30 – Aug 6
Sweet cornSow outdoorsApr 30 – Jul 4
Watermelon & cantaloupeSow outdoorsMay 14 – Jun 14
OkraSow outdoorsMay 7 – May 30
PeasSow outdoors (spring)Mar 14 – Apr 29
PotatoesPlant outdoors (spring)Mar 14 – May 14
OnionsStart seeds indoors (spring)Jan 31 – Feb 27
OnionsTransplant outdoors (spring)Mar 31 – Apr 29
BroccoliStart seeds indoors (spring)Feb 24 – Mar 30
BroccoliTransplant outdoors (spring)Mar 31 – Apr 29
BroccoliStart seeds indoors (fall)Jun 24 – Jul 4
BroccoliTransplant outdoors (fall)Jul 24 – Aug 4
CabbageStart seeds indoors (spring)Feb 14 – Mar 14
CabbageTransplant outdoors (spring)Mar 14 – Apr 14
CabbageStart seeds indoors (fall)Jun 14 – Jul 14
CabbageTransplant outdoors (fall)Jul 14 – Aug 14
Leaf lettuceSow outdoors (spring)Mar 14 – May 30
Leaf lettuceSow outdoors (fall)Jul 14 – Aug 30
SpinachSow outdoors (spring)Mar 7 – Apr 20
SpinachSow outdoors (fall)Jul 31 – Sep 4
RadishesSow outdoors (spring)Mar 14 – May 4
RadishesSow outdoors (fall)Jul 14 – Sep 14
KaleSow outdoors (spring)Mar 31 – Apr 20
KaleSow outdoors (fall)Jul 7 – Aug 14
CarrotsSow outdoors (spring)Apr 14 – May 30
CarrotsSow outdoors (fall)Jun 14 – Jul 30
GarlicPlant outdoors (fall)Oct 14 – Nov 14

Where these dates come from

ZIP code 52646 is matched to the NOAA station New Boston Dam 17, IL, 10.3 km away, at 548 ft elevation (7 ft higher than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
New Boston Dam 17, IL (used)548 ftApr 14Oct 24
Gladstone Dam 18, IL538 ftApr 8Oct 29
Aledo, IL730 ftApr 22Oct 19
Monmouth 4Nw, IL724 ftApr 22Oct 14

Frost dates near Oakville

Frequently asked questions

When is the last frost in Oakville, IA?
For ZIP code 52646, the average last spring frost (32°F) is April 14, based on NOAA 1991-2020 climate normals for the New Boston Dam 17, IL weather station. There is a 1-in-10 chance of a frost after May 2.
When is the first frost in Oakville, IA?
The average first fall frost (32°F) is October 24. There is a 1-in-10 chance of frost by October 9, so tender plants are at risk from that point on.
How long is the growing season in 52646?
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.