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When to plant in Bothell, WA

USDA Zone 8b

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

With about 260 frost-free days, Bothell supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. In zone 8b, Bothell supports a wide range of perennials year-round; the frost dates above are what set your annual vegetable timing.

Station · SEATTLE SAND PT WSFO · 10.3 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 BothellA year-band showing 32°F frost risk from January to December for Bothell: 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 Bothell’s own odds, recorded at SEATTLE SAND PT WSFO.

Frost-probability curves for BothellProbability 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 Bothell, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 18 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
10 km · 18 m elevation
SPRING
Mar 8
FALL
Nov 23
EVERETT SNOHOMISH AP
16 km · 185 m elevation
SPRING
Mar 9
FALL
Nov 17
MONROE
18 km · 37 m elevation
SPRING
Apr 17
FALL
Oct 23

Bothell planting FAQ

When is the last spring frost in Bothell, WA?

Plan for the last spring frost in Bothell 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 Bothell, WA?

The first fall frost in Bothell typically arrives around November 23 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Bothell in?

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

How long is the growing season in Bothell?

Bothell 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 Bothell?

For Bothell, 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 Bothell

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

Nearby cities

8 within reach

Frost dates recorded at SEATTLE SAND PT WSFO, 10 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 Bothell, WA — Frost Dates & Zone 8b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00094290. Retrieved from https://blissgarden.com/washington/bothell.
When to Plant in Bothell, WA — Frost Dates & Zone 8b — BlissGarden