FrostDateByZip

Frost dates for 59454Kevin, MT

The average last spring frost in Kevin is May 23 and the average first fall frost is September 16, giving a typical growing season of about 115 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
May 23

Safer after Jun 6 (1-in-10 risk)

Average first fall frost
Sep 16

Possible by Sep 3 (1-in-10 risk)

Growing season
115 days

Last frost typically in 208 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 23 · Jun 5 · Jun 21Aug 23 · Sep 5 · Sep 1890 days100%
Frost / freeze (32°F)May 11 · May 23 · Jun 6Sep 3 · Sep 16 · Sep 28115 days100%
Hard freeze (28°F)Apr 30 · May 10 · May 22Sep 13 · Sep 26 · Oct 7138 days100%

Planting calendar for Kevin

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 22 – Jun 28
TomatoesTransplant outdoorsJun 8 – May 27
PeppersStart seeds indoorsApr 22 – May 23
PeppersTransplant outdoorsJun 22 – Jul 23
EggplantStart seeds indoorsMay 9 – Jun 7
EggplantTransplant outdoorsJun 22 – Jul 23
CucumbersSow outdoorsJun 22 – Jun 6
Summer squashSow outdoorsJun 8 – Jul 23
Winter squash & pumpkinsSow outdoorsJun 22 – Jul 23
Snap beansSow outdoorsJun 8 – Jun 29
Sweet cornSow outdoorsJun 8 – May 27
Watermelon & cantaloupeSow outdoorsJun 22 – Jul 23
OkraSow outdoorsJun 15 – Jul 8
PeasSow outdoors (spring)Apr 22 – Jun 7
PotatoesPlant outdoors (spring)Apr 22 – Jun 22
OnionsStart seeds indoors (spring)Mar 11 – Apr 7
OnionsTransplant outdoors (spring)May 9 – Jun 7
BroccoliStart seeds indoors (spring)Apr 4 – May 8
BroccoliTransplant outdoors (spring)May 9 – Jun 7
BroccoliStart seeds indoors (fall)May 17 – May 27
BroccoliTransplant outdoors (fall)Jun 16 – Jun 27
CabbageStart seeds indoors (spring)Mar 25 – Apr 22
CabbageTransplant outdoors (spring)Apr 22 – May 23
CabbageStart seeds indoors (fall)May 7 – Jun 6
CabbageTransplant outdoors (fall)Jun 6 – Jul 7
Leaf lettuceSow outdoors (spring)Apr 22 – Jul 8
Leaf lettuceSow outdoors (fall)Jun 6 – Jul 23
SpinachSow outdoors (spring)Apr 15 – May 29
SpinachSow outdoors (fall)Jun 23 – Jul 28
RadishesSow outdoors (spring)Apr 22 – Jun 12
RadishesSow outdoors (fall)Jun 6 – Aug 7
KaleSow outdoors (spring)May 9 – May 29
KaleSow outdoors (fall)May 30 – Jul 7
CarrotsSow outdoors (spring)May 23 – Jul 8
CarrotsSow outdoors (fall)May 7 – Jun 22
GarlicPlant outdoors (fall)Sep 6 – Oct 7

Where these dates come from

ZIP code 59454 is matched to the NOAA station Shelby, MT, 27.7 km away, at 3,325 ft elevation (54 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Shelby, MT (used)3,325 ftMay 23Sep 16
Sunburst 8 E, MT3,700 ftMay 17Sep 25
Sweetgrass, MT3,510 ftMay 15Sep 25
Cut Bank Muni Ap, MT3,838 ftMay 24Sep 15

Frost dates near Kevin

Frequently asked questions

When is the last frost in Kevin, MT?
For ZIP code 59454, the average last spring frost (32°F) is May 23, based on NOAA 1991-2020 climate normals for the Shelby, MT weather station. There is a 1-in-10 chance of a frost after June 6.
When is the first frost in Kevin, MT?
The average first fall frost (32°F) is September 16. There is a 1-in-10 chance of frost by September 3, so tender plants are at risk from that point on.
How long is the growing season in 59454?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 115 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.