FrostDateByZip

Frost dates for 97486Umpqua, OR

The average last spring frost in Umpqua is April 27 and the average first fall frost is October 19, giving a typical growing season of about 176 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Apr 27

Safer after May 15 (1-in-10 risk)

Average first fall frost
Oct 19

Possible by Sep 26 (1-in-10 risk)

Growing season
176 days

Last frost typically in 176 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 21 · Jun 12Sep 5 · Sep 27 · Oct 19126 days100%
Frost / freeze (32°F)Apr 2 · Apr 27 · May 15Sep 26 · Oct 19 · Nov 14176 days100%
Hard freeze (28°F)Feb 15 · Mar 21 · Apr 27Oct 19 · Nov 13 · Dec 13239 days100%

Planting calendar for Umpqua

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 27 – Jun 2
TomatoesTransplant outdoorsMay 13 – Jun 29
PeppersStart seeds indoorsMar 27 – Apr 27
PeppersTransplant outdoorsMay 27 – Jun 27
EggplantStart seeds indoorsApr 13 – May 12
EggplantTransplant outdoorsMay 27 – Jun 27
CucumbersSow outdoorsMay 27 – Jul 9
Summer squashSow outdoorsMay 13 – Jun 27
Winter squash & pumpkinsSow outdoorsMay 27 – Jun 27
Snap beansSow outdoorsMay 13 – Aug 1
Sweet cornSow outdoorsMay 13 – Jun 29
Watermelon & cantaloupeSow outdoorsMay 27 – Jun 27
OkraSow outdoorsMay 20 – Jun 12
PeasSow outdoors (spring)Mar 27 – May 12
PotatoesPlant outdoors (spring)Mar 27 – May 27
OnionsStart seeds indoors (spring)Feb 13 – Mar 12
OnionsTransplant outdoors (spring)Apr 13 – May 12
BroccoliStart seeds indoors (spring)Mar 9 – Apr 12
BroccoliTransplant outdoors (spring)Apr 13 – May 12
BroccoliStart seeds indoors (fall)Jun 19 – Jun 29
BroccoliTransplant outdoors (fall)Jul 19 – Jul 30
CabbageStart seeds indoors (spring)Feb 27 – Mar 27
CabbageTransplant outdoors (spring)Mar 27 – Apr 27
CabbageStart seeds indoors (fall)Jun 9 – Jul 9
CabbageTransplant outdoors (fall)Jul 9 – Aug 9
Leaf lettuceSow outdoors (spring)Mar 27 – Jun 12
Leaf lettuceSow outdoors (fall)Jul 9 – Aug 25
SpinachSow outdoors (spring)Mar 20 – May 3
SpinachSow outdoors (fall)Jul 26 – Aug 30
RadishesSow outdoors (spring)Mar 27 – May 17
RadishesSow outdoors (fall)Jul 9 – Sep 9
KaleSow outdoors (spring)Apr 13 – May 3
KaleSow outdoors (fall)Jul 2 – Aug 9
CarrotsSow outdoors (spring)Apr 27 – Jun 12
CarrotsSow outdoors (fall)Jun 9 – Jul 25
GarlicPlant outdoors (fall)Oct 9 – Nov 9

Where these dates come from

ZIP code 97486 is matched to the NOAA station Idleyld Park 4 Ne, OR, 46.1 km away, at 1,080 ft elevation (42 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Idleyld Park 4 Ne, OR (used)1,080 ftApr 27Oct 19
Winchester, OR460 ftMar 31Nov 5
Roseburg Rgnl Ap, OR525 ftMar 19Nov 20
Roseburg Kqen, OR425 ftMar 23Nov 18

Frost dates near Umpqua

Frequently asked questions

When is the last frost in Umpqua, OR?
For ZIP code 97486, the average last spring frost (32°F) is April 27, based on NOAA 1991-2020 climate normals for the Idleyld Park 4 Ne, OR weather station. There is a 1-in-10 chance of a frost after May 15.
When is the first frost in Umpqua, OR?
The average first fall frost (32°F) is October 19. There is a 1-in-10 chance of frost by September 26, so tender plants are at risk from that point on.
How long is the growing season in 97486?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 176 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.