When to plant in Kelso, WA
USDA Zone 8bEverything below — frost dates, hardiness zone, and what to plant when in Kelso, Washington — is derived from the closest NOAA station with complete climate normals.
Zone 8b means many perennials and even some tender shrubs overwinter in Kelso, while your frost dates still decide when annuals go out.
The average first fall frost in Kelso is now 6 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
LONGVIEW · 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 Kelso’s own odds, recorded at LONGVIEW.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 24 | May 3 | Apr 15 | Oct 2 | Oct 21 | Nov 10 |
| 32°F | May 2 | Apr 8 | Mar 11 | Oct 17 | Nov 5 | Nov 28 |
| 28°F | Apr 4 | Mar 6 | Feb 6 | Oct 31 | Nov 24 | Dec 20 |
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 Kelso, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 30 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.
Kelso planting FAQ
When is the last spring frost in Kelso, WA?
Plan for the last spring frost in Kelso around April 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 Kelso, WA?
Expect Kelso's first fall frost near November 5 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Kelso in?
Kelso is in USDA hardiness zone 8b. In zone 8b, winters are mild — many tender perennials overwinter here.
How long is the growing season in Kelso?
There are roughly 211 frost-free days in Kelso (a long growing season), running from the average last frost around April 8 to the first fall frost near November 5.
When should I plant tomatoes in Kelso?
In Kelso, start tomato seeds indoors around February 11–February 25, then transplant seedlings outdoors around April 15 once the danger of frost has passed.
Never miss a window in Kelso
An email when it’s time to start seeds, transplant, and sow — timed to Kelso’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Longview · 7 km
- St. Helens · 29 km
- Ridgefield · 37 km
- Battle Ground · 46 km
- Mount Vista · 47 km
- Felida · 47 km
- Salmon Creek · 48 km
- Hazel Dell · 52 km
Frost dates recorded at LONGVIEW, 4 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 Kelso, WA — Frost Dates & Zone 8b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00454769. Retrieved from https://blissgarden.com/washington/kelso.