FrostDateByZip

Frost dates for 50078Ferguson, IA

The average last spring frost in Ferguson is April 28 and the average first fall frost is October 7, giving a typical growing season of about 162 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Apr 28

Safer after May 11 (1-in-10 risk)

Average first fall frost
Oct 7

Possible by Sep 22 (1-in-10 risk)

Growing season
162 days

Last frost typically in 177 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 25 · May 7 · May 20Sep 16 · Sep 28 · Oct 11144 days100%
Frost / freeze (32°F)Apr 13 · Apr 28 · May 11Sep 22 · Oct 7 · Oct 21162 days100%
Hard freeze (28°F)Apr 3 · Apr 17 · May 2Oct 1 · Oct 18 · Oct 31181 days100%

Planting calendar for Ferguson

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 28 – Jun 3
TomatoesTransplant outdoorsMay 14 – Jun 17
PeppersStart seeds indoorsMar 28 – Apr 28
PeppersTransplant outdoorsMay 28 – Jun 28
EggplantStart seeds indoorsApr 14 – May 13
EggplantTransplant outdoorsMay 28 – Jun 28
CucumbersSow outdoorsMay 28 – Jun 27
Summer squashSow outdoorsMay 14 – Jun 28
Winter squash & pumpkinsSow outdoorsMay 28 – Jun 28
Snap beansSow outdoorsMay 14 – Jul 20
Sweet cornSow outdoorsMay 14 – Jun 17
Watermelon & cantaloupeSow outdoorsMay 28 – Jun 28
OkraSow outdoorsMay 21 – Jun 13
PeasSow outdoors (spring)Mar 28 – May 13
PotatoesPlant outdoors (spring)Mar 28 – May 28
OnionsStart seeds indoors (spring)Feb 14 – Mar 13
OnionsTransplant outdoors (spring)Apr 14 – May 13
BroccoliStart seeds indoors (spring)Mar 10 – Apr 13
BroccoliTransplant outdoors (spring)Apr 14 – May 13
BroccoliStart seeds indoors (fall)Jun 7 – Jun 17
BroccoliTransplant outdoors (fall)Jul 7 – Jul 18
CabbageStart seeds indoors (spring)Feb 28 – Mar 28
CabbageTransplant outdoors (spring)Mar 28 – Apr 28
CabbageStart seeds indoors (fall)May 28 – Jun 27
CabbageTransplant outdoors (fall)Jun 27 – Jul 28
Leaf lettuceSow outdoors (spring)Mar 28 – Jun 13
Leaf lettuceSow outdoors (fall)Jun 27 – Aug 13
SpinachSow outdoors (spring)Mar 21 – May 4
SpinachSow outdoors (fall)Jul 14 – Aug 18
RadishesSow outdoors (spring)Mar 28 – May 18
RadishesSow outdoors (fall)Jun 27 – Aug 28
KaleSow outdoors (spring)Apr 14 – May 4
KaleSow outdoors (fall)Jun 20 – Jul 28
CarrotsSow outdoors (spring)Apr 28 – Jun 13
CarrotsSow outdoors (fall)May 28 – Jul 13
GarlicPlant outdoors (fall)Sep 27 – Oct 28

Where these dates come from

ZIP code 50078 is matched to the NOAA station Marshalltown, IA, 15 km away, at 870 ft elevation (62 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Marshalltown, IA (used)870 ftApr 28Oct 7
Marshalltown Muni Ap, IA974 ftApr 30Oct 6
Toledo 3N, IA935 ftApr 30Oct 9
Grinnell 3 Sw, IA905 ftMay 3Oct 6

Frost dates near Ferguson

Frequently asked questions

When is the last frost in Ferguson, IA?
For ZIP code 50078, the average last spring frost (32°F) is April 28, based on NOAA 1991-2020 climate normals for the Marshalltown, IA weather station. There is a 1-in-10 chance of a frost after May 11.
When is the first frost in Ferguson, IA?
The average first fall frost (32°F) is October 7. There is a 1-in-10 chance of frost by September 22, so tender plants are at risk from that point on.
How long is the growing season in 50078?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 162 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.