FrostDateByZip

Frost dates for 55057Northfield, MN

The average last spring frost in Northfield is May 5 and the average first fall frost is October 5, giving a typical growing season of about 152 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
May 5

Safer after May 19 (1-in-10 risk)

Average first fall frost
Oct 5

Possible by Sep 21 (1-in-10 risk)

Growing season
152 days

Last frost typically in 183 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)May 1 · May 15 · May 29Sep 12 · Sep 27 · Oct 9135 days100%
Frost / freeze (32°F)Apr 22 · May 5 · May 19Sep 21 · Oct 5 · Oct 17152 days100%
Hard freeze (28°F)Apr 11 · Apr 26 · May 10Oct 1 · Oct 13 · Oct 27170 days100%

Planting calendar for Northfield

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 indoorsApr 4 – Jun 10
TomatoesTransplant outdoorsMay 21 – Jun 15
PeppersStart seeds indoorsApr 4 – May 5
PeppersTransplant outdoorsJun 4 – Jul 5
EggplantStart seeds indoorsApr 21 – May 20
EggplantTransplant outdoorsJun 4 – Jul 5
CucumbersSow outdoorsJun 4 – Jun 25
Summer squashSow outdoorsMay 21 – Jul 5
Winter squash & pumpkinsSow outdoorsJun 4 – Jul 5
Snap beansSow outdoorsMay 21 – Jul 18
Sweet cornSow outdoorsMay 21 – Jun 15
Watermelon & cantaloupeSow outdoorsJun 4 – Jul 5
OkraSow outdoorsMay 28 – Jun 20
PeasSow outdoors (spring)Apr 4 – May 20
PotatoesPlant outdoors (spring)Apr 4 – Jun 4
OnionsStart seeds indoors (spring)Feb 21 – Mar 20
OnionsTransplant outdoors (spring)Apr 21 – May 20
BroccoliStart seeds indoors (spring)Mar 17 – Apr 20
BroccoliTransplant outdoors (spring)Apr 21 – May 20
BroccoliStart seeds indoors (fall)Jun 5 – Jun 15
BroccoliTransplant outdoors (fall)Jul 5 – Jul 16
CabbageStart seeds indoors (spring)Mar 7 – Apr 4
CabbageTransplant outdoors (spring)Apr 4 – May 5
CabbageStart seeds indoors (fall)May 26 – Jun 25
CabbageTransplant outdoors (fall)Jun 25 – Jul 26
Leaf lettuceSow outdoors (spring)Apr 4 – Jun 20
Leaf lettuceSow outdoors (fall)Jun 25 – Aug 11
SpinachSow outdoors (spring)Mar 28 – May 11
SpinachSow outdoors (fall)Jul 12 – Aug 16
RadishesSow outdoors (spring)Apr 4 – May 25
RadishesSow outdoors (fall)Jun 25 – Aug 26
KaleSow outdoors (spring)Apr 21 – May 11
KaleSow outdoors (fall)Jun 18 – Jul 26
CarrotsSow outdoors (spring)May 5 – Jun 20
CarrotsSow outdoors (fall)May 26 – Jul 11
GarlicPlant outdoors (fall)Sep 25 – Oct 26

Where these dates come from

ZIP code 55057 is matched to the NOAA station Faribault, MN, 18.4 km away, at 970 ft elevation (25 ft higher than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Faribault, MN (used)970 ftMay 5Oct 5
Farmington 3 Nw, MN980 ftApr 27Oct 10
Rosemount Rsch & Outreach Ctr, MN945 ftMay 2Oct 5
Owatonna, MN1,140 ftMay 5Oct 6

Frost dates near Northfield

Frequently asked questions

When is the last frost in Northfield, MN?
For ZIP code 55057, the average last spring frost (32°F) is May 5, based on NOAA 1991-2020 climate normals for the Faribault, MN weather station. There is a 1-in-10 chance of a frost after May 19.
When is the first frost in Northfield, MN?
The average first fall frost (32°F) is October 5. There is a 1-in-10 chance of frost by September 21, so tender plants are at risk from that point on.
How long is the growing season in 55057?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 152 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.