Generally — Most Areas
wild lupine (zones 3-8) suits most of Washington (4a-9b) — zones 4-8 are in range, and the rest of the state is the exception.
Wild Lupine in Washington — the short answer
Wild Lupine in Washington: hardy in zones 3–8, full sun, against a state median of ~208 frost-free days.
- Plant zones
- 3-8
- Manual horticultural correction (source not retained); NC State Extension and Missouri Botanical Garden, with the remaining rows from other published sources or Growable Ground compilation
- Washington zones
- 4a-9b
- USDA PHZM 2023
- Frost window
- Mar 16 - Apr 15 – Oct 24 - Nov 18
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 131 days
- NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS and university Extension sources — per-field provenance varies and is published with the dataset.
Your yard isn't the whole zone.
Washington spans zones 4a-9b, but your yard has its own microclimate — slope, trees, and low spots shift frost and sun across a single parcel. Enter your address and we'll score wild lupine against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Washington is not one climate
A single Washington answer averages 39 counties whose growing seasons are 169 days apart — from 131 frost-free days in Whatcom County to 300 in San Juan County. Which end of that your land sits nearer changes what wild lupine can finish before the first hard freeze.
The middle half of 39 counties runs 192–248 days, with a median of 208 days — a 169-day span end to end.
Measured across 39 Washington counties. NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze. Quartiles are order statistics — every figure shown is a value a real county recorded, not an interpolation. Your own site sits somewhere inside this range; a parcel report resolves where.
Where in Washington Fits Best
Wild Lupine is rated for zones 3–8 — a cold floor USDA puts at -40 to -30°F. Against Washington’s 39 counties that band holds in 26 of them, and the line runs at Ferry County (zone 6a), the coldest county still inside it.
Inside zones 3–8
26 counties
- Okanogan County · zone 6a
- Pend Oreille County · zone 6a
- Douglas County · zone 6b
3 of 26 shown
Above the zone 8 ceiling
13 counties
- Clallam County · zone 8b
- Clark County · zone 8b
- Cowlitz County · zone 8b
3 of 13 shown
Too little winter chill rather than too much cold — a low-chill selection is what changes it.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. A zone is a 10°F band of average annual extreme minimum temperature, so the floor above is the band the plant's rating denotes, not a single measured kill point. Slope, shelter and cold-air drainage routinely move a site half a zone either way from its county figure — which is the part only your address resolves.
Even within Washington's zones 4a-9b, county microclimates differ enough to change what thrives. These counties carry the closest zone match for wild lupine (USDA PHZM 2023):
Zone Comparison
Wild Lupine Needs
- USDA Zones: 3-8
- Frost-Free Days: 100+
- Sun: Full Sun
- Mature size: 2 ft tall
- Picking window: ~30 days of harvest
- Drought tolerance: High
Washington Has
- USDA Zones: 4a-9b
- Last Hard Freeze (28°F): Mar 16 - Apr 15
- First Hard Freeze (28°F): Oct 24 - Nov 18
- Annual Rainfall: 6-90 inches
- Common Soils: Volcanic ash, Silt loam (Palouse), Sandy loam
Plant Zone Range (zones 3-8)
Preferred Soil pH
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS, and university Extension sources — per-field provenance varies and is published with the dataset. State data: USDA ARS PHZM 2023, NOAA Climate Normals, NRCS SSURGO.
When to Plant Wild Lupine in Washington
The frost window
Across Washington, the last spring hard freeze (28°F) clears between Mar 16 and Apr 15, and the first fall hard freeze lands between Oct 24 and Nov 18 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 192-day window you can count on — up to 247 days on a mild site in a kind year. That marks the hard freeze, not the last light frost, so tender transplants usually wait another 2-3 weeks.
Frost hardiness
Wild Lupine takes cold down to about 21.2°F before a freeze kills it (FAO ECOCROP), so you can plant on the early side of Washington's window — even a few weeks before the final hard freeze. That is the point where cold damages growing tissue, not a winter-survival floor — an established perennial comes through far colder while dormant, which is what its hardiness zone tells you.
When to start the seed
Those dates are when wild lupine goes out, not when it starts. It is sown under cover about 8 weeks ahead, so counting back from Washington's late-side last freeze of Apr 15 is what fixes your sowing date — and a yard that clears frost earlier than the state's late date starts earlier still.
Frost window: NOAA Climate Normals 1991-2020. Plant timing fields: Growable Ground Plant Database — frost-free days from FAO ECOCROP, days to harvest from university Extension production guides, and growing-degree-day and chill-hour minimums that are compilation estimates rather than published figures. Your site's own frost dates can run earlier or later than the state range — a parcel report pins them down.
Growing Season Fit
The zone check says wild lupine survives winter in part of Washington, not across all of it. Whether the season is long enough — and warm enough — is a different question.
Frost-free days
Wild Lupine wants 100+ frost-free days; a typical Washington site sees ~208 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.
GDD and chill-hour figures are computed from PRISM 1991-2020 monthly climate normals; frost-free days from NOAA Regional Climate Centers ACIS, 1991-2020. Each is the state median across its counties (P25/P75 span the within-state spread). Hardiness-zone range is USDA PHZM 2023.
Soil + Drainage Fit
Wild Lupine tolerates a wide pH range (pH 4.9-8.2) — 3.3 units, acid ground through alkaline — so soil acidity is rarely what limits it in Washington. A soil test is still worth having, but for what else it tells you about this site, not to clear this plant. It will grow across that whole span, but it does best between pH 5.5 and 7 — worth knowing before you decide whether a Washington soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Washington site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.
Plant pH requirements: FAO ECOCROP and USDA PLANTS, with the remaining rows from other published sources or Growable Ground compilation. Drainage: FAO ECOCROP, with the remaining rows from other published sources or Growable Ground compilation. Washington soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
What Else to Consider for Wild Lupine in Washington
Zone compatibility tells you about winter cold survival — but Washington growers also need to think about:
Extreme rain divide: 90+ inches west, 6 inches east of Cascades
East side requires irrigation — no rain from June through September
Slug and root rot pressure on the wet west side
Short seasons at elevation in the Cascades and northeast corners
What to actually do about these — and the constraints that apply to every Washington grower, not just wild lupine — is covered on the Washington growing guide.
Timing shifts within Washington
Wild Lupine needs about 100 days of frost-free season to complete its cycle. Even Whatcom County — Washington’s shortest season at 131 frost-free days — clears that by 31 days, so season length isn’t the constraint anywhere in Washington. What varies is your own parcel.
Across Washington’s 39 counties the frost-free season runs from 131 days in Whatcom County to 300 days in San Juan County — a spread of 169 days, which is why a single statewide planting date misleads. The median Washington county sees 208 frost-free days, leaving wild lupine about 108 days of slack on a typical parcel — room for a second sowing where the season runs long.
County last-freeze dates and frost-free day counts: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F freeze (earlier than the folk 32°F "last frost"). Wild Lupine's 100-day requirement: USDA PLANTS / Growable Ground plant database (minimum frost-free days). A parcel report resolves your address's own frost dates.
Pollinator + Wildlife Value
Wild Lupine draws native bees and butterflies (high value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, wild lupine can only work that bloom inside Washington's frost window — roughly 208 days, opening after the last 28°F freeze (Mar 16 - Apr 15) and closing at the first (Oct 24 - Nov 18), per NOAA Regional Climate Centers ACIS, 1991-2020.
Washington Cooperative Extension
For Washington-specific cultivar recommendations, planting calendars, and pest pressure for wild lupine, the canonical source is WSU Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Wild Lupine native to Washington?
Wild Lupine is native to parts of the Lower 48, but the USDA PLANTS Database (accessed 2026-07-01) does not document a native range in Washington. It can still earn a place in a Washington garden — the zone comparison above tells you whether it will thrive.
Looking for plants that belong here? The Washington growing guide lists USDA-documented natives for the state.
Native-range data: USDA PLANTS Database state-distribution records, accessed 2026-07-01.
Common Questions About Growing Wild Lupine in Washington
When can I plant Wild Lupine in Washington?
Washington's last spring hard freeze (28°F) clears between Mar 16 and Apr 15, and the first fall hard freeze lands between Oct 24 and Nov 18 (NOAA Regional Climate Centers ACIS, 1991-2020). Wild Lupine takes cold to about 21.2°F before a freeze kills it (FAO ECOCROP — the point where cold damages growing tissue, not a winter-survival floor), so plant on the early side of that window — even ahead of the final hard freeze.
What hardiness zone is Wild Lupine grown in across Washington?
Washington spans USDA hardiness zones 4a-9b (USDA ARS PHZM 2023). Wild Lupine carries a range of zones 3-8, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Washington site have?
A typical Washington site sees ~208 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Wild Lupine needs 100+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date.
Is Wild Lupine native to Washington?
Wild Lupine is native to parts of the Lower 48, but the USDA PLANTS Database (accessed 2026-07-01) does not document a native range in Washington. It can still earn a place in a Washington garden — the zone comparison above tells you whether it will thrive.
How should I amend the soil for Wild Lupine in Washington?
Wild Lupine tolerates pH 4.9-8.2 and well (dry spells) drainage (FAO ECOCROP). That is a 3.3-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Washington site — amend for drainage and organic matter first.
Will Wild Lupine actually grow on my specific land in Washington?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores wild lupine against your address's exact soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.
Check your specific parcel in Washington
State-level data is a sketch. Your Growable Ground report scores wild lupine against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Washington wild lupine averages can't show:
We read public map data around Washington — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Washington wild lupine average
Explore More
Growing guides for wild lupine
Explore Washington county by county
Washington carries 39 counties with their own USDA zone — a sample of the growing pages for wild lupine there:
Where else wild lupine grows
Wild Lupine's zone band crosses state lines — these are the states closest to Washington in winter climate where it also has a page, plus the far ends of its range. Each one re-answers the question with that state's own record.
More to grow in Washington
Washington has a growing page for 1,038 plants — a rotating sample of the rest of the shelf.
Last updated: