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When to plant in Bellevue, WA

USDA Zone 9a

Bellevue, Washington frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.

Bellevue enjoys a long ~260-day frost-free season — you can succession-sow, fit in a second crop, and grow long-season heat-lovers with room to spare. In zone 9a, frost is a minor factor for Bellevue — most perennials thrive, and annual vegetables can go out early and stay late.

Station · SEATTLE SAND PT WSFO · 12.4 km
Last spring frost
March 8
50% chance · 32°F
First fall frost
November 23
50% chance · 32°F
Growing season
260 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for BellevueA year-band showing 32°F frost risk from January to December for Bellevue: last spring frost around March 8, first fall frost around November 23, about 260 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

SEATTLE SAND PT WSFO · 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 Bellevue’s own odds, recorded at SEATTLE SAND PT WSFO.

Frost-probability curves for BellevueProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around March 8 and the first fall frost around November 23, giving about 260 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°FApr 26Apr 4Mar 17Oct 24Nov 5Nov 22
32°FMar 29Mar 8Feb 13Nov 4Nov 23Dec 16
28°FMar 1Feb 11Dec 27Nov 17Dec 11Jan 17

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 15 days
Brussels Sprouts
August 3August 17

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 Bellevue, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 13 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.

SEATTLE SAND PT WSFO
Primary
12 km · 18 m elevation
SPRING
Mar 8
FALL
Nov 23
RENTON MUNI AP
12 km · 9 m elevation
SPRING
Mar 13
FALL
Nov 16
SEATTLE BOEING FLD
13 km · 6 m elevation
SPRING
Mar 13
FALL
Nov 17

Bellevue planting FAQ

When is the last spring frost in Bellevue, WA?

Plan for the last spring frost in Bellevue around March 8 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.

When is the first fall frost in Bellevue, WA?

In Bellevue, the first 32°F freeze of fall lands around November 23 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Bellevue in?

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

How long is the growing season in Bellevue?

Bellevue has about 260 frost-free days — a long growing season — between the average last spring frost (March 8) and first fall frost (November 23).

When should I plant tomatoes in Bellevue?

For Bellevue, sow tomatoes indoors about January 11–January 25 and move the seedlings out around March 15, after the last spring frost.

Planting reminders

Never miss a window in Bellevue

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

Nearby cities

8 within reach

Frost dates recorded at SEATTLE SAND PT WSFO, 12 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 Bellevue, WA — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00094290. Retrieved from https://blissgarden.com/washington/bellevue.
When to Plant in Bellevue, WA — Frost Dates & Zone 9a — BlissGarden