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When to plant in Maple Valley, WA

USDA Zone 8b

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

Zone 8b means many perennials and even some tender shrubs overwinter in Maple Valley, while your frost dates still decide when annuals go out.

Station · LANDSBURG · 5.6 km
Last spring frost
April 20
50% chance · 32°F
First fall frost
October 25
50% chance · 32°F
Growing season
188 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Maple ValleyA year-band showing 32°F frost risk from January to December for Maple Valley: last spring frost around April 20, first fall frost around October 25, about 188 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

LANDSBURG · 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 Maple Valley’s own odds, recorded at LANDSBURG.

Frost-probability curves for Maple ValleyProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 20 and the first fall frost around October 25, giving about 188 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°FJun 7May 10Apr 23Sep 19Oct 6Oct 26
32°FMay 10Apr 20Mar 31Oct 5Oct 25Nov 12
28°FApr 16Mar 24Feb 28Oct 24Nov 12Dec 8

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

What to plant now

TODAY · JULY 19
Fall sowopen now
Brussels Sprouts
July 5July 19
Fall sowopen now
Rutabaga
July 19August 2
Fall sowin 14 days
Broccoli
August 2August 16
Fall sowin 14 days
Cabbage
August 2August 16
Fall sowin 14 days
Carrot
August 2August 16
Fall sowin 14 days
Cauliflower
August 2August 16
Fall sowin 14 days
Napa Cabbage
August 2August 30
Fall sowin 28 days
Beet
August 16August 30
Fall sowin 28 days
Collards
August 16September 13
Fall sowin 28 days
Endive
August 16August 30
Fall sowin 28 days
Escarole
August 16August 30
Fall sowin 28 days
Fennel (Bulb)
August 16August 30
Fall sowin 28 days
Kale
August 16September 13
Fall sowin 28 days
Kohlrabi
August 16September 13
Fall sowin 28 days
Peas
August 16August 30
Fall sowin 28 days
Radicchio
August 16August 30
Fall sowin 28 days
Swiss Chard
August 16August 30
Fall sowin 28 days
Turnip
August 16September 13

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 Maple Valley, 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.

LANDSBURG
Primary
6 km · 163 m elevation
SPRING
Apr 20
FALL
Oct 25
PALMER 3 ESE
15 km · 280 m elevation
SPRING
Apr 3
FALL
Nov 11
KENT
17 km · 9 m elevation
SPRING
Mar 20
FALL
Nov 10

Maple Valley planting FAQ

When is the last spring frost in Maple Valley, WA?

Plan for the last spring frost in Maple Valley around April 20 (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 Maple Valley, WA?

The first fall frost in Maple Valley typically arrives around October 25 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Maple Valley in?

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

How long is the growing season in Maple Valley?

There are roughly 188 frost-free days in Maple Valley (a moderate growing season), running from the average last frost around April 20 to the first fall frost near October 25.

When should I plant tomatoes in Maple Valley?

In Maple Valley, start tomato seeds indoors around February 23–March 9, then transplant seedlings outdoors around April 27 once the danger of frost has passed.

Planting reminders

Never miss a window in Maple Valley

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

Nearby cities

8 within reach

Frost dates recorded at LANDSBURG, 6 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 Maple Valley, WA — Frost Dates & Zone 8b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00454486. Retrieved from https://blissgarden.com/washington/maple-valley.
When to Plant in Maple Valley, WA — Frost Dates & Zone 8b — BlissGarden