FrostDateByZip

Frost dates for 84790Saint George, UT

The average last spring frost in Saint George is March 14 and the average first fall frost is November 10, giving a typical growing season of about 239 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Mar 14

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

Average first fall frost
Nov 10

Possible by Oct 27 (1-in-10 risk)

Growing season
239 days

First frost typically in 14 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)Mar 17 · Apr 3 · Apr 21Oct 19 · Nov 1 · Nov 12208 days100%
Frost / freeze (32°F)Feb 27 · Mar 14 · Apr 6Oct 27 · Nov 10 · Nov 22239 days100%
Hard freeze (28°F)Feb 7 · Feb 27 · Mar 17Nov 7 · Nov 20 · Dec 3266 days100%

Planting calendar for Saint George

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 indoorsFeb 11 – Apr 19
TomatoesTransplant outdoorsMar 30 – Jul 21
PeppersStart seeds indoorsFeb 11 – Mar 14
PeppersTransplant outdoorsApr 13 – May 14
EggplantStart seeds indoorsFeb 28 – Mar 29
EggplantTransplant outdoorsApr 13 – May 14
CucumbersSow outdoorsApr 13 – Jul 31
Summer squashSow outdoorsMar 30 – May 14
Winter squash & pumpkinsSow outdoorsApr 13 – May 14
Snap beansSow outdoorsMar 30 – Aug 23
Sweet cornSow outdoorsMar 30 – Jul 21
Watermelon & cantaloupeSow outdoorsApr 13 – May 14
OkraSow outdoorsApr 6 – Apr 29
PeasSow outdoors (spring)Feb 11 – Mar 29
PotatoesPlant outdoors (spring)Feb 11 – Apr 13
OnionsStart seeds indoors (spring)Dec 31 – Jan 27
OnionsTransplant outdoors (spring)Feb 28 – Mar 29
BroccoliStart seeds indoors (spring)Jan 24 – Feb 27
BroccoliTransplant outdoors (spring)Feb 28 – Mar 29
BroccoliStart seeds indoors (fall)Jul 11 – Jul 21
BroccoliTransplant outdoors (fall)Aug 10 – Aug 21
CabbageStart seeds indoors (spring)Jan 14 – Feb 11
CabbageTransplant outdoors (spring)Feb 11 – Mar 14
CabbageStart seeds indoors (fall)Jul 1 – Jul 31
CabbageTransplant outdoors (fall)Jul 31 – Aug 31
Leaf lettuceSow outdoors (spring)Feb 11 – Apr 29
Leaf lettuceSow outdoors (fall)Jul 31 – Sep 16
SpinachSow outdoors (spring)Feb 4 – Mar 20
SpinachSow outdoors (fall)Aug 17 – Sep 21
RadishesSow outdoors (spring)Feb 11 – Apr 3
RadishesSow outdoors (fall)Jul 31 – Oct 1
KaleSow outdoors (spring)Feb 28 – Mar 20
KaleSow outdoors (fall)Jul 24 – Aug 31
CarrotsSow outdoors (spring)Mar 14 – Apr 29
CarrotsSow outdoors (fall)Jul 1 – Aug 16
GarlicPlant outdoors (fall)Oct 31 – Dec 1

Where these dates come from

ZIP code 84790 is matched to the NOAA station St George, UT, 5.9 km away, at 2,857 ft elevation (301 ft higher than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
St George, UT (used)2,857 ftMar 14Nov 10
La Verkin, UT3,194 ftApr 1Nov 5
Veyo Powerhouse, UT4,600 ftApr 9Nov 5
Beaver Dam, AZ1,931 ftMar 7Nov 19

Frost dates near Saint George

Frequently asked questions

When is the last frost in Saint George, UT?
For ZIP code 84790, the average last spring frost (32°F) is March 14, based on NOAA 1991-2020 climate normals for the St George, UT weather station. There is a 1-in-10 chance of a frost after April 6.
When is the first frost in Saint George, UT?
The average first fall frost (32°F) is November 10. There is a 1-in-10 chance of frost by October 27, so tender plants are at risk from that point on.
How long is the growing season in 84790?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 239 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.