Willow Creek, California, sits in USDA hardiness zone 9a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Expect artichoke, fig, california poppy, and cabbage to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Even in Willow Creek, 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 Willow Creek 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 Willow Creek — soil, climate, flood, and parcel records. How we handle your address.
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Willow Creek — the short answer
Willow Creek, California: USDA zone 9a, about 278 days between hard freezes, across 19K acres of town.
- USDA zone
- 9a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 1
- Humboldt County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 4
- Humboldt County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~278
- Humboldt County normal — NOAA 1991–2020, nearest to this town
- Town area
- 19K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. No 30-year normal resolves at this town’s own centroid, so the hard-freeze dates are Humboldt County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9a is Willow Creek's average, not your lot's — a low corner or a tree line moves it. Against Willow Creek's 278-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Willow Creek
Each reading below is measured for Willow Creek itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsWillow Creek runs about 278 days between hard freezes (read from Humboldt County, the closest normal to Willow Creek) — close to year-round growing.
Frost is rarely the limit here; winter plantings are as real as summer ones, and the harder question is which crops shrug off the summer heat.
Grow cool-season crops through the mild winter, and choose heat-tolerant varieties for the summer beds.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredWillow Creek sits in USDA hardiness zone 9a.
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 Willow Creek is in
Willow Creek sits in the Klamath Mountains/California High North Coast Range — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Willow Creek's own centroid, and it is not what its county reads: Humboldt County is mostly Coast Range. The wider page above you is answering a different question about different ground.
What Grows in Willow Creek
Every plant below cleared Willow Creek's own zone 9a and its 278-day season. Each card opens that plant's California profile. How we score.
Is it too late to plant in Willow Creek?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Feb 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 1 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 4 — long-season crops need about 90 days of runway, quick greens only 30. With almost year-round growing weather, timing is about heat and rainfall more than frost — some bench is always in play.
What's on the federal record near Willow Creek
Closest first, within ~10 miles of Willow Creek. Listing isn't leaking, and distance isn't exposure.
- L & M Renner Inc - Willow Creek CardlockUnderground Storage Tanks · 2300 ft
- L & M RENNER INCBrownfields · 2300 ft
- L & M RENNER INC DBA WILLOW CREEK CARDLOCKBrownfields · 2500 ft
- MERCER,FASER CO INC/WILLOW CREEKBrownfields · 2600 ft
- 007N005E29R001HNitrate · 0.6 mi
- REDWOOD OIL CO/WILLOW CREEK CHEVRONBrownfields · 0.6 mi
- Redwood Oil Co - Willow Creek Chevron Gasoline StationUnderground Storage Tanks · 0.6 mi
- BIGFOOT EQUIPMENT & REPAIRBrownfields · 0.6 mi
- PG&E - WILLOW CREEK SERVICE CENTERBrownfields · 0.6 mi
- SPEED EXBrownfields · 0.6 mi
- Speedex - Gas StationUnderground Storage Tanks · 0.6 mi
- FRONTIER CALIFORNIA INCBrownfields · 0.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Willow Creek'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 Willow Creek.
Total Sites
45
within ~10 miles of Willow Creek
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Willow Creek
Severity Distribution
within ~10 miles of Willow Creek
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Willow Creek, two things run higher than the national average within ~10 miles of Willow Creek — Mining (13 sites) and Brownfields (23 sites). That's not a problem with your land — it's information about it.
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 Willow Creek
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 Willow Creek average
Your land is one point inside Willow Creek
Everything above resolves to Willow Creek as a whole — one PHZM band, read across 19K acres, with hard-freeze dates borrowed from Humboldt County’s record because no 30-year normal resolves at this town’s own centroid. 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 Willow Creek Average
Willow Creek Average
- ●USDA Zones 9a, averaged across Willow Creek
- ●One soil character for all of Willow Creek
- ●Frost dates read at Willow Creek's scale: Mar 1 to Dec 4
YOUR Parcel
- ✓Your exact zone, not Willow Creek's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Willow Creek
Pull a site-specific report for your exact address in Willow Creek, California — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Willow Creek averages can't show:
We read public map data around Willow Creek — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Willow Creek average
How we know this about Willow Creek
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 Humboldt County’s record, because none resolves here; 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 Willow Creek
When does frost risk typically end in Willow Creek?
The last hard freeze (28°F) in Willow Creek typically lands around Mar 1, 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 Mar 22.
When is the first frost in Willow Creek?
The first hard freeze (28°F) in Willow Creek typically arrives around Dec 4, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 20, so the watching starts about Nov 4 — about 278 days after the spring freeze cleared.
How long is the growing season in Willow Creek?
Measured between 28°F hard freezes, Willow Creek sees about 278 frost-free days — roughly Mar 1 through Dec 4, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 22 to Nov 20, about 243 days.
Is the soil safe to grow vegetables in Willow Creek?
The federal record around Willow Creek is a meaningful one — 45 documented sites, mostly Brownfields entries (23), the nearest Underground Storage Tanks record about 0.4 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 Willow Creek?
From about Nov 4 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 Dec 4 (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 Dec 4. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Willow Creek's scale — its 9a band and its 278-day season. Your yard writes its own version of Willow Creek'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 Willow Creek’s own scale
5 of the readings below were taken at Willow Creek's own scale — the 19,398 acres it covers and 45 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Willow Creek's own USDA hardiness band, zones 9aUSDA PHZM 2023
- 45 documented contamination sites on the federal record near Willow Creek, the closest Underground Storage Tanks record about 0.4 miles out from the town centreFederal environmental registers
- Willow Creek's boundary and the 19,398 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9a and a ~278-day seasonGrowable Ground crop-matching engine
- Willow Creek sits in the Klamath Mountains/California High North Coast Range — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Willow Creek has no normal of its own, so its county's is the closest measured readfrom Humboldt County
- Soil character — no town-scale survey exists, so Willow Creek's 19,398 acres read through its county's SSURGO summaryfrom Humboldt County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Humboldt 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 Humboldt County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Willow Creek's 19,398 acreswhy one lot differs from the next →
- Which side of Willow Creek you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 19,398 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.4 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 Willow Creek-wide figureread your own land →
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