Willow Valley, Arizona, sits in USDA hardiness zone 9a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
These conditions suit artichoke, fig, california poppy, and cabbage — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Even in Willow Valley, 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 Valley 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 Valley — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Willow Valley — the short answer
Willow Valley, Arizona: USDA zone 9a, about 242 days between hard freezes, across 3K acres of town.
- USDA zone
- 9a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 21
- Mohave County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Nov 18
- Mohave County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~242
- Mohave County normal — NOAA 1991–2020, nearest to this town
- Town area
- 3K 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 Mohave County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9a is Willow Valley's average, not your lot's — a low corner or a tree line moves it. Against Willow Valley's 242-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Willow Valley
Each reading below is measured for Willow Valley itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsWillow Valley runs about 242 days between hard freezes (read from Mohave County, the closest normal to Willow Valley) — 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
MeasuredWillow Valley 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 Valley is in
Willow Valley sits in the Mojave Basin and Range — EPA Level III, inside the wider North American Deserts. That is read at Willow Valley's own centroid rather than borrowed from Mohave County.
What Grows in Willow Valley
Every plant below cleared Willow Valley's own zone 9a and its 242-day season. Each card opens that plant's Arizona profile. How we score.
Is it too late to plant in Willow Valley?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Feb 21; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 21 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 18 — long-season crops need about 90 days of runway, quick greens only 30. A long window like this one runs successions deep into fall — and even its last weeks take quick greens and garlic.
Documented around Willow Valley
Survey cells within 31 miles of Willow Valley checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 191 miles off. What to watch for.
What's on the federal record near Willow Valley
Closest first, within ~10 miles of Willow Valley. Listing isn't leaking, and distance isn't exposure.
- B-18-22 27BBC1Nitrate · 0.7 mi
- AT&T MOBILITYBrownfields · 1.4 mi
- HARTER FARMS LLCBrownfields · 1.6 mi
- BARTCOUnderground Storage Tanks · 1.7 mi
- MOHAVE VALLEY ELEMENTARY SCHOOLUnderground Storage Tanks · 1.9 mi
- HANCOCK FARMS IIUnderground Storage Tanks · 2.0 mi
- FORT MOJAVE BATTERY REMOVAL ACTION.Brownfields · 2.0 mi
- PARCEL 225-27-128Underground Storage Tanks · 2.3 mi
- RIVER VALLEY TAVERNUnderground Storage Tanks · 2.5 mi
- A TO Z COLLISIONUnderground Storage Tanks · 2.6 mi
- SOUTHERN CALIFORNIA GAS COBrownfields · 2.7 mi
- FAMILY DOLLAR #10037Brownfields · 2.9 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Willow Valley'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 Valley.
Total Sites
137
within ~10 miles of Willow Valley
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Willow Valley
Severity Distribution
within ~10 miles of Willow Valley
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Willow Valley, two things run higher than the national average within ~10 miles of Willow Valley — Mining (18 sites) and Brownfields (68 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around 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 Valley
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 Valley average
Your land is one point inside Willow Valley
Everything above resolves to Willow Valley as a whole — one PHZM band, read across 3K acres, with hard-freeze dates borrowed from Mohave 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 Valley Average
Willow Valley Average
- ●USDA Zones 9a, averaged across Willow Valley
- ●One soil character for all of Willow Valley
- ●Frost dates read at Willow Valley's scale: Mar 21 to Nov 18
YOUR Parcel
- ✓Your exact zone, not Willow Valley's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Willow Valley
Pull a site-specific report for your exact address in Willow Valley, Arizona — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Willow Valley averages can't show:
We read public map data around Willow Valley — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Willow Valley average
How we know this about Willow Valley
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 Mohave 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 Valley
When does frost risk typically end in Willow Valley?
The last hard freeze (28°F) in Willow Valley typically lands around Mar 21, 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 11.
When is the first frost in Willow Valley?
The first hard freeze (28°F) in Willow Valley typically arrives around Nov 18, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 4, so the watching starts about Oct 19 — about 242 days after the spring freeze cleared.
How long is the growing season in Willow Valley?
Measured between 28°F hard freezes, Willow Valley sees about 242 frost-free days — roughly Mar 21 through Nov 18, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 11 to Nov 4, about 207 days.
Is the soil safe to grow vegetables in Willow Valley?
The federal record around Willow Valley is a meaningful one — 137 documented sites, mostly Brownfields entries (68), the nearest Nitrate record about 0.7 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 Valley?
From about Oct 19 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 18 (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 18. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Willow Valley's scale — its 9a band and its 242-day season. Your yard writes its own version of Willow Valley'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 Valley’s own scale
6 of the readings below were taken at Willow Valley's own scale — the 3,159 acres it covers and 137 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Willow Valley's own USDA hardiness band, zones 9aUSDA PHZM 2023
- 137 documented contamination sites on the federal record near Willow Valley, the closest Nitrate record about 0.7 miles out from the town centreFederal environmental registers
- Willow Valley's boundary and the 3,159 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9a and a ~242-day seasonGrowable Ground crop-matching engine
- The ecoregion at Willow Valley's own centroid, the Mojave Basin and RangeUS EPA Level III Ecoregions
- Lanternfly survey cells around Willow Valley checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- The 28°F hard-freeze dates — Willow Valley has no normal of its own, so its county's is the closest measured readfrom Mohave County
- Soil character — no town-scale survey exists, so Willow Valley's 3,159 acres read through its county's SSURGO summaryfrom Mohave County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Mohave County
- The growing challenges every Arizona grower plans around — written at state scale, so they stay on the state guidefrom Arizona
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Mohave County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Willow Valley's 3,159 acreswhy one lot differs from the next →
- Which side of Willow Valley you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 3,159 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 0.7 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 Valley-wide figureread your own land →
More in Arizona
Nearby growing guides