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When to plant in Bainbridge Island, WA

USDA Zone 9a

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

These dates come from a station roughly 15 km away, the closest with full normals; terrain around Bainbridge Island (elevation, water, pavement) can move your real frost dates a few days either way. Zone 9a is warm enough that Bainbridge Island can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · BREMERTON · 15.5 km
Last spring frost
March 29
50% chance · 32°F
First fall frost
November 14
50% chance · 32°F
Growing season
230 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Bainbridge IslandA year-band showing 32°F frost risk from January to December for Bainbridge Island: last spring frost around March 29, first fall frost around November 14, about 230 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

BREMERTON · 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 Bainbridge Island’s own odds, recorded at BREMERTON.

Frost-probability curves for Bainbridge IslandProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around March 29 and the first fall frost around November 14, giving about 230 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 13Apr 25Apr 7Oct 4Oct 27Nov 13
32°FApr 24Mar 29Mar 5Oct 26Nov 14Dec 1
28°FMar 27Feb 27Jan 24Nov 10Nov 30Dec 24

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 6 days
Brussels Sprouts
July 25August 8
Fall sowin 20 days
Rutabaga
August 8August 22

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

Nearby weather stations

3 within 20 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.

BREMERTON
Primary
15 km · 34 m elevation
SPRING
Mar 29
FALL
Nov 14
SEATTLE SAND PT WSFO
20 km · 18 m elevation
SPRING
Mar 8
FALL
Nov 23
SEATTLE BOEING FLD
20 km · 6 m elevation
SPRING
Mar 13
FALL
Nov 17

Bainbridge Island planting FAQ

When is the last spring frost in Bainbridge Island, WA?

Plan for the last spring frost in Bainbridge Island around March 29 (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 Bainbridge Island, WA?

In Bainbridge Island, the first 32°F freeze of fall lands around November 14 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Bainbridge Island in?

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

How long is the growing season in Bainbridge Island?

There are roughly 230 frost-free days in Bainbridge Island (a long growing season), running from the average last frost around March 29 to the first fall frost near November 14.

When should I plant tomatoes in Bainbridge Island?

In Bainbridge Island, start tomato seeds indoors around February 1–February 15, then transplant seedlings outdoors around April 5 once the danger of frost has passed.

Planting reminders

Never miss a window in Bainbridge Island

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

Nearby cities

8 within reach

Frost dates recorded at BREMERTON, 15 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 Bainbridge Island, WA — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00450872. Retrieved from https://blissgarden.com/washington/bainbridge-island.