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When to plant in Newberg, OR

USDA Zone 8b

Here are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Newberg, Oregon — all computed from Newberg's nearest NOAA weather station.

A generous ~246-day season lets Newberg gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. Zone 8b means many perennials and even some tender shrubs overwinter in Newberg, while your frost dates still decide when annuals go out.

Station · REX 1 S · 3.7 km
Last spring frost
March 21
50% chance · 32°F
First fall frost
November 22
50% chance · 32°F
Growing season
246 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for NewbergA year-band showing 32°F frost risk from January to December for Newberg: last spring frost around March 21, first fall frost around November 22, about 246 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

REX 1 S · 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 Newberg’s own odds, recorded at REX 1 S.

Frost-probability curves for NewbergProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around March 21 and the first fall frost around November 22, giving about 246 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 6Apr 21Mar 30Oct 20Nov 3Nov 22
32°FApr 19Mar 21Feb 23Nov 4Nov 22Dec 12
28°FMar 11Feb 15Jan 3Nov 15Dec 10Jan 12

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

What to plant now

TODAY · JULY 19
Fall sowin 14 days
Brussels Sprouts
August 2August 16
Fall sowin 28 days
Rutabaga
August 16August 30

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

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

Nearby weather stations

3 within 17 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.

REX 1 S
Primary
4 km · 157 m elevation
SPRING
Mar 21
FALL
Nov 22
AURORA STATE AP
16 km · 60 m elevation
SPRING
Mar 16
FALL
Nov 14
N WILLAMETTE EXP STN
17 km · 46 m elevation
SPRING
Mar 18
FALL
Nov 13

Newberg planting FAQ

When is the last spring frost in Newberg, OR?

Newberg's average last spring frost falls near March 21 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.

When is the first fall frost in Newberg, OR?

The first fall frost in Newberg typically arrives around November 22 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Newberg in?

Newberg is in USDA hardiness zone 8b. In zone 8b, winters are mild — many tender perennials overwinter here.

How long is the growing season in Newberg?

There are roughly 246 frost-free days in Newberg (a long growing season), running from the average last frost around March 21 to the first fall frost near November 22.

When should I plant tomatoes in Newberg?

In Newberg, start tomato seeds indoors around January 24–February 7, then transplant seedlings outdoors around March 28 once the danger of frost has passed.

Planting reminders

Never miss a window in Newberg

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

Nearby cities

8 within reach

Frost dates recorded at REX 1 S, 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 Newberg, OR — Frost Dates & Zone 8b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00357127. Retrieved from https://blissgarden.com/oregon/newberg.
When to Plant in Newberg, OR — Frost Dates & Zone 8b — BlissGarden