Green Bluff, Washington, sits in USDA hardiness zone 6b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Crops well matched to these conditions include cabbage, blackberry, california poppy, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Even in Green Bluff, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Green Bluff lot. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around Green Bluff — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Green Bluff — the short answer
Green Bluff, Washington: USDA zone 6b, about 191 days between hard freezes, across 5K acres of town.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 14
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 22
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~191
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 5K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are this town’s own 28°F normals: light frosts run a few weeks past them, and tender transplants usually wait 2–3 weeks after the last hard freeze.
Hardiness Zone Range
Zone 6b is Green Bluff's average, not your lot's — a low corner or a tree line moves it. Against Green Bluff's 191-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Green Bluff
Each reading below is measured for Green Bluff itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredGreen Bluff runs about 191 days between hard freezes — a moderate growing season.
There is room for the full run of cool-season crops plus a warm-season main crop, but the calendar is tight enough that a late spring or early fall frost still decides how much finishes.
Time warm-season transplants to your last hard freeze, and a few weeks of season extension turns a near-miss harvest into a sure one.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredGreen Bluff sits in USDA hardiness zone 6b.
The zone sets which perennials, shrubs, and fruit trees live through an average winter here — a plant rated for a colder zone is a safe bet, one rated warmer needs winter protection or gets treated as an annual.
Match perennials and fruit to the zone before you buy, so nothing you plant is a gamble against the cold.
USDA PHZM 2023
The kind of country Green Bluff is in
Green Bluff sits in the Northern Rockies — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Green Bluff's own centroid, and it is not what its county reads: Spokane County is mostly Columbia Plateau. The wider page above you is answering a different question about different ground.
What Grows in Green Bluff
Every plant below cleared Green Bluff's own zone 6b and its 191-day season. Each card opens that plant's Washington profile. How we score.
Is it too late to plant in Green Bluff?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 17; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 14 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 22 — long-season crops need about 90 days of runway, quick greens only 30. As the window narrows, the plantings just get faster — fall brassicas, then greens, then garlic to finish.
What's on the federal record near Green Bluff
Closest first, within ~10 miles of Green Bluff. Listing isn't leaking, and distance isn't exposure.
- GREENBLUFF TRADING POSTUnderground Storage Tanks · 0.6 mi
- NEOWISE, LLCBrownfields · 0.7 mi
- COLBERT ELEMENTARY SCHOOLUnderground Storage Tanks · 0.7 mi
- ED J KERNKAMPUnderground Storage Tanks · 1.0 mi
- IDEAL EXCAVATORSUnderground Storage Tanks · 2.1 mi
- GRAYMAR ENVIRONMENTAL SERVICES LLCBrownfields · 2.2 mi
- NW CHRISTIAN HIGH SCHOOLUnderground Storage Tanks · 2.7 mi
- 27N/43E-26M02Nitrate · 3.2 mi
- WA AGR SPOKANE 2Brownfields · 3.4 mi
- MAVERIK 447Underground Storage Tanks · 3.6 mi
- COLBERT STOREUnderground Storage Tanks · 3.7 mi
- LES & ROD GRIGGSUnderground Storage Tanks · 3.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Green Bluff's center, not your beds. Run your own address for what's upwind of you specifically.
Environmental Intelligence
The counts behind that headline — every source type on the record near Green Bluff.
Sources Checked
within ~10 miles of Green Bluff
Severity Distribution
within ~10 miles of Green Bluff
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Green Bluff, two things run higher than the national average within ~10 miles of Green Bluff — PFAS (8 sites) and Superfund (8 sites). That's not a problem with your land — it's information about it.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Green Bluff
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,086 plant recommendations.
25+ data sources read at your address, not the Green Bluff average
Your land is one point inside Green Bluff
Everything above resolves to Green Bluff as a whole — one PHZM band and one 28°F frost record, read across 5K acres. Your parcel is one point inside that footprint. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at town scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better local average.
Your Lot vs the Green Bluff Average
Green Bluff Average
- ●USDA Zones 6b, averaged across Green Bluff
- ●One soil character for all of Green Bluff
- ●Frost dates read at Green Bluff's scale: Apr 14 to Oct 22
YOUR Parcel
- ✓Your exact zone, not Green Bluff's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Green Bluff
Pull a site-specific report for your exact address in Green Bluff, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Green Bluff averages can't show:
We read public map data around Green Bluff — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Green Bluff average
How we know this about Green Bluff
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this town’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Green Bluff’s own record; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at town grain anywhere on this page — there is no town-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Green Bluff
When does frost risk typically end in Green Bluff?
The last hard freeze (28°F) in Green Bluff typically lands around Apr 14, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about May 5.
When is the first frost in Green Bluff?
The first hard freeze (28°F) in Green Bluff typically arrives around Oct 22, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 8, so the watching starts about Sep 22 — about 191 days after the spring freeze cleared.
How long is the growing season in Green Bluff?
Measured between 28°F hard freezes, Green Bluff sees about 191 frost-free days — roughly Apr 14 through Oct 22, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 5 to Oct 8, about 156 days.
Is the soil safe to grow vegetables in Green Bluff?
The federal record around Green Bluff runs heavier than most — 529 documented sites, mostly Underground Storage Tanks entries (241), the nearest Underground Storage Tanks record about 0.6 miles out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
How do I protect my plants from frost in Green Bluff?
From about Sep 22 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Oct 22 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Oct 22. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Green Bluff's scale — its 6b band and its 191-day season. Your yard writes its own version of Green Bluff's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Green Bluff’s own scale
6 of the readings below were taken at Green Bluff's own scale — its own ~191-day season between 28°F freezes, the 4,526 acres it covers and 529 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Green Bluff's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Green Bluff's own 28°F hard-freeze dates, about Apr 14 and Oct 22 and the ~191-day span between themNOAA 1991–2020 Climate Normals
- 529 documented contamination sites on the federal record near Green Bluff, the closest Underground Storage Tanks record about 0.6 miles out from the town centreFederal environmental registers
- Green Bluff's boundary and the 4,526 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~191-day seasonGrowable Ground crop-matching engine
- Green Bluff sits in the Northern Rockies — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Green Bluff's 4,526 acres read through its county's SSURGO summaryfrom Spokane County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Spokane County
- The growing challenges every Washington grower plans around — written at state scale, so they stay on the state guidefrom Washington
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Spokane County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Green Bluff's 4,526 acreswhy one lot differs from the next →
- Which side of Green Bluff you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 4,526 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.6 miles out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Green Bluff-wide figureread your own land →