When to plant in Tumwater, WA
USDA Zone 8aEverything below — frost dates, hardiness zone, and what to plant when in Tumwater, Washington — is derived from the closest NOAA station with complete climate normals.
Zone 8a means many perennials and even some tender shrubs overwinter in Tumwater, while your frost dates still decide when annuals go out.
Frost probability
OLYMPIA AP · 1991–2020The 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 Tumwater’s own odds, recorded at OLYMPIA AP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 31 | May 15 | Apr 30 | Sep 12 | Sep 28 | Oct 14 |
| 32°F | May 15 | Apr 29 | Apr 11 | Sep 28 | Oct 14 | Nov 1 |
| 28°F | Apr 29 | Apr 5 | Mar 12 | Oct 9 | Nov 1 | Nov 24 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Tumwater, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 32 km · complete 32°F normalsWhen 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.
Tumwater planting FAQ
When is the last spring frost in Tumwater, WA?
Tumwater's average last spring frost falls near April 29 — 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 Tumwater, WA?
Expect Tumwater's first fall frost near October 14 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Tumwater in?
Tumwater is in USDA hardiness zone 8a. In zone 8a, winters are mild — many tender perennials overwinter here.
How long is the growing season in Tumwater?
There are roughly 168 frost-free days in Tumwater (a moderate growing season), running from the average last frost around April 29 to the first fall frost near October 14.
When should I plant tomatoes in Tumwater?
In Tumwater, start tomato seeds indoors around March 4–March 18, then transplant seedlings outdoors around May 6 once the danger of frost has passed.
Never miss a window in Tumwater
An email when it’s time to start seeds, transplant, and sow — timed to Tumwater’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Olympia · 6 km
- Lacey · 11 km
- Yelm · 21 km
- Fort Lewis · 29 km
- Centralia · 30 km
- Shelton · 30 km
- Lakewood · 35 km
- University Place · 38 km
Frost dates recorded at OLYMPIA AP, 2 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Tumwater, WA — Frost Dates & Zone 8a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00024227. Retrieved from https://blissgarden.com/washington/tumwater.