Dunsmuir, California, sits in USDA hardiness zone 8a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
The conditions favor cabbage, fig, california poppy, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Dunsmuir, 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 Dunsmuir 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 Dunsmuir — soil, climate, flood, and parcel records. How we handle your address.
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Dunsmuir — the short answer
Dunsmuir, California: USDA zone 8a, about 230 days between hard freezes, across 1K acres of city.
- USDA zone
- 8a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 31
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 16
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~230
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 1K 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 8a is Dunsmuir's average, not your lot's — a low corner or a tree line moves it. Against Dunsmuir's 230-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Dunsmuir
Each reading below is measured for Dunsmuir itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredDunsmuir runs about 230 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredDunsmuir sits in USDA hardiness zone 8a.
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 Dunsmuir is in
Dunsmuir sits in the Klamath Mountains/California High North Coast Range — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Dunsmuir's own centroid rather than borrowed from Siskiyou County.
What Grows in Dunsmuir
Every plant below cleared Dunsmuir's own zone 8a and its 230-day season. Each card opens that plant's California profile. How we score.
Is it too late to plant in Dunsmuir?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Mar 3; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 31 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 16 — long-season crops need about 90 days of runway, quick greens only 30. There is slack in a calendar like this — late plantings, second rounds of favorites, and a fall bench that keeps beds working.
What's on the federal record near Dunsmuir
Closest first, within ~10 miles of Dunsmuir. Listing isn't leaking, and distance isn't exposure.
- PACIFIC BELLBrownfields · 1700 ft
- CASTLE ROCK WATER COMPANYBrownfields · 1900 ft
- STAGE STOP IBrownfields · 0.7 mi
- Dunsmuir ChevronUnderground Storage Tanks · 0.7 mi
- MCCLOUD HEALTHCARE CLINIC INC DBA DUNSMUIR COMMUNITY HEALTH CENTERBrownfields · 0.7 mi
- CALTRANS DISTRICT 2 BIBSON MTC STABrownfields · 0.7 mi
- AT&T MOBILITYBrownfields · 1.2 mi
- Hedge Creek Copper ProspectMining · 1.3 mi
- SOUTHERN PACIFIC TRANSPORTATION COSuperfund · 1.3 mi
- SOUTHERN PACIFIC TRANSPORTATION COBrownfields · 1.3 mi
- DUNSMUIR MERCURY RESIDENCESuperfund · 1.4 mi
- CITY OF DUNSMUIR CORP YARDBrownfields · 1.4 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Dunsmuir'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 Dunsmuir.
Total Sites
131
within ~10 miles of Dunsmuir
Risk Level
Elevated
Highest-severity
2 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Dunsmuir
Severity Distribution
within ~10 miles of Dunsmuir
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Dunsmuir, two things run higher than the national average within ~10 miles of Dunsmuir — Mining (20 sites) and Brownfields (94 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.
Brownfields: Brownfield sites are former commercial or industrial properties where legacy soil contamination (heavy metals, PAHs, petroleum compounds) may persist.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Check EPA brownfield remediation status — many sites have completed cleanup with institutional controls.
Check your specific parcel in Dunsmuir
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 Dunsmuir average
Your land is one point inside Dunsmuir
Everything above resolves to Dunsmuir as a whole — one PHZM band and one 28°F frost record, read across 1K 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 city 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 Dunsmuir Average
Dunsmuir Average
- ●USDA Zones 8a, averaged across Dunsmuir
- ●One soil character for all of Dunsmuir
- ●Frost dates read at Dunsmuir's scale: Mar 31 to Nov 16
YOUR Parcel
- ✓Your exact zone, not Dunsmuir's 8a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Dunsmuir
Pull a site-specific report for your exact address in Dunsmuir, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Dunsmuir averages can't show:
We read public map data around Dunsmuir — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Dunsmuir average
How we know this about Dunsmuir
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Dunsmuir’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 city grain anywhere on this page — there is no city-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 Dunsmuir
When does frost risk typically end in Dunsmuir?
The last hard freeze (28°F) in Dunsmuir typically lands around Mar 31, 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 Apr 21.
When is the first frost in Dunsmuir?
The first hard freeze (28°F) in Dunsmuir typically arrives around Nov 16, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 2, so the watching starts about Oct 17 — about 230 days after the spring freeze cleared.
How long is the growing season in Dunsmuir?
Measured between 28°F hard freezes, Dunsmuir sees about 230 frost-free days — roughly Mar 31 through Nov 16, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 21 to Nov 2, about 195 days.
Is the soil safe to grow vegetables in Dunsmuir?
The federal record around Dunsmuir is a meaningful one — 131 documented sites, mostly Brownfields entries (94), the nearest Brownfields record about 0.3 miles out — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
How do I protect my plants from frost in Dunsmuir?
From about Oct 17 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 Nov 16 (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 Nov 16. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Dunsmuir's scale — its 8a band and its 230-day season. Your yard writes its own version of Dunsmuir'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 Dunsmuir’s own scale
6 of the readings below were taken at Dunsmuir's own scale — its own ~230-day season between 28°F freezes, the 1,027 acres it covers and 131 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Dunsmuir's own USDA hardiness band, zones 8aUSDA PHZM 2023
- Dunsmuir's own 28°F hard-freeze dates, about Mar 31 and Nov 16 and the ~230-day span between themNOAA 1991–2020 Climate Normals
- 131 documented contamination sites on the federal record near Dunsmuir, the closest Brownfields record about 0.3 miles out from the town centreFederal environmental registers
- Dunsmuir's boundary and the 1,027 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8a and a ~230-day seasonGrowable Ground crop-matching engine
- The ecoregion at Dunsmuir's own centroid, the Klamath Mountains/California High North Coast RangeUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Dunsmuir's 1,027 acres read through its county's SSURGO summaryfrom Siskiyou County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Siskiyou County
- The growing challenges every California grower plans around — written at state scale, so they stay on the state guidefrom California
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Siskiyou County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Dunsmuir's 1,027 acreswhy one lot differs from the next →
- Which side of Dunsmuir you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,027 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.3 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 Dunsmuir-wide figureread your own land →
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