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When to plant in Coos Bay, OR

USDA Zone 9a

Everything below — frost dates, hardiness zone, and what to plant when in Coos Bay, Oregon — is derived from the closest NOAA station with complete climate normals.

A generous ~291-day season lets Coos Bay gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. In zone 9a, frost is a minor factor for Coos Bay — most perennials thrive, and annual vegetables can go out early and stay late.

Station · NORTH BEND RGNL AP · 3.7 km
Last spring frost
February 21
50% chance · 32°F
First fall frost
December 9
50% chance · 32°F
Growing season
291 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Coos BayA year-band showing 32°F frost risk from January to December for Coos Bay: last spring frost around February 21, first fall frost around December 9, about 291 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average last spring frost in Coos Bay is now 6 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

NORTH BEND RGNL AP · 1991–2020

The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Coos Bay’s own odds, recorded at NORTH BEND RGNL AP.

Frost-probability curves for Coos BayProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 21 and the first fall frost around December 9, giving about 291 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FMay 1Apr 2Mar 1Oct 24Nov 15Dec 11
32°FMar 25Feb 21Dec 31Nov 12Dec 9Jan 28
28°FFeb 22Jan 4Dec 3Nov 25Dec 22Feb 15

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19

Nothing new to sow or transplant outdoors in the next few weeks — a seasonal lull. Check the full-year calendar below for the next window.

Add the next planting windows to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in Coos Bay, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 22 km · complete 32°F normals

When stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.

NORTH BEND RGNL AP
Primary
4 km · 5 m elevation
SPRING
Feb 21
FALL
Dec 9
COOS BAY 8 SW
14 km · 4 m elevation
SPRING
Apr 15
FALL
Oct 31
COQUILLE CITY
22 km · 7 m elevation
SPRING
Mar 28
FALL
Nov 6

Coos Bay planting FAQ

When is the last spring frost in Coos Bay, OR?

On average, the last spring frost in Coos Bay is around February 21 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.

When is the first fall frost in Coos Bay, OR?

In Coos Bay, the first 32°F freeze of fall lands around December 9 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Coos Bay in?

Coos Bay is in USDA hardiness zone 9a. In zone 9a, winters are mild — many tender perennials overwinter here.

How long is the growing season in Coos Bay?

Coos Bay has about 291 frost-free days — a long growing season — between the average last spring frost (February 21) and first fall frost (December 9).

When should I plant tomatoes in Coos Bay?

For Coos Bay, sow tomatoes indoors about December 27–January 10 and move the seedlings out around February 28, after the last spring frost.

Planting reminders

Never miss a window in Coos Bay

An email when it’s time to start seeds, transplant, and sow — timed to Coos Bay’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at NORTH BEND RGNL AP, 4 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in Coos Bay, OR — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00024284. Retrieved from https://blissgarden.com/oregon/coos-bay.
When to Plant in Coos Bay, OR — Frost Dates & Zone 9a — BlissGarden