Phoenix, Arizona, sits in USDA hardiness zone 9b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
On paper, okra, meyer lemon, california poppy, and artichoke all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Phoenix, 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 Phoenix 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 Phoenix — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Phoenix — the short answer
Phoenix, Arizona: USDA zone 9b, about 345 days between hard freezes, across 332K acres of city.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 15
- Maricopa County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 26
- Maricopa County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~345
- Maricopa County normal — NOAA 1991–2020, nearest to this town
- City area
- 332K 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 Maricopa County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9b is Phoenix's average, not your lot's — a low corner or a tree line moves it. Against Phoenix's 345-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Phoenix
Each reading below is measured for Phoenix itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsPhoenix runs about 345 days between hard freezes (read from Maricopa County, the closest normal to Phoenix) — 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
MeasuredPhoenix sits in USDA hardiness zone 9b.
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 Phoenix is in
Phoenix sits in the Sonoran Basin and Range — EPA Level III, inside the wider North American Deserts. That is read at Phoenix's own centroid rather than borrowed from Maricopa County.
What Grows in Phoenix
Every plant below cleared Phoenix's own zone 9b and its 345-day season. Each card opens that plant's Arizona profile. How we score.
Is it too late to plant in Phoenix?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Jan 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Jan 15 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 26 — long-season crops need about 90 days of runway, quick greens only 30. And with a calendar this mild, the honest answer is that planting barely stops — winter opens seasons colder regions never see.
Documented around Phoenix
Survey cells within 31 miles of Phoenix checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 295 miles off. What to watch for.
What's on the federal record near Phoenix
Closest first, within ~10 miles of Phoenix. Listing isn't leaking, and distance isn't exposure.
- WELLMAN'S TRANSMISSIONUnderground Storage Tanks · 350 ft
- PIONEER ROOFING CO - STORAGE YARDUnderground Storage Tanks · 600 ft
- RELIABLE ROOFINGUnderground Storage Tanks · 800 ft
- TERMINEX INTERNATIONALUnderground Storage Tanks · 800 ft
- A DEAL CONCRETEUnderground Storage Tanks · 850 ft
- PROGRESSIVE CONCRETE WORKSUnderground Storage Tanks · 950 ft
- CIRCLE K #2700530Underground Storage Tanks · 1100 ft
- DEAL CONCRETEUnderground Storage Tanks · 1100 ft
- PARCEL 158-32-016Underground Storage Tanks · 1200 ft
- WESTERN PLUMBING INCUnderground Storage Tanks · 1300 ft
- MELVIN CONCRETE INCUnderground Storage Tanks · 1500 ft
- A-03-03 30CDANitrate · 1500 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Phoenix'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 Phoenix.
Total Sites
3,933
within ~10 miles of Phoenix
Risk Level
Elevated
Highest-severity
21 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Phoenix
Severity Distribution
within ~10 miles of Phoenix
Highest-Severity Sites
Know Before You Grow
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
Check your specific parcel in Phoenix
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 Phoenix average
Your land is one point inside Phoenix
Everything above resolves to Phoenix as a whole — one PHZM band, read across 332K acres, with hard-freeze dates borrowed from Maricopa County’s record because no 30-year normal resolves at this city’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 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 Phoenix Average
Phoenix Average
- ●USDA Zones 9b, averaged across Phoenix
- ●One soil character for all of Phoenix
- ●Frost dates read at Phoenix's scale: Jan 15 to Dec 26
YOUR Parcel
- ✓Your exact zone, not Phoenix's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Phoenix
Pull a site-specific report for your exact address in Phoenix, Arizona — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Phoenix averages can't show:
We read public map data around Phoenix — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Phoenix average
How we know this about Phoenix
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 Maricopa 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 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 Phoenix
When does frost risk typically end in Phoenix?
The last hard freeze (28°F) in Phoenix typically lands around Jan 15, 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 Feb 5.
When is the first frost in Phoenix?
The first hard freeze (28°F) in Phoenix typically arrives around Dec 26, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Dec 12, so the watching starts about Nov 26 — about 345 days after the spring freeze cleared.
How long is the growing season in Phoenix?
Measured between 28°F hard freezes, Phoenix sees about 345 frost-free days — roughly Jan 15 through Dec 26, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 5 to Dec 12, about 310 days.
Is the soil safe to grow vegetables in Phoenix?
The federal record around Phoenix is a meaningful one — 3,933 documented sites, mostly Underground Storage Tanks entries (2,215), the nearest Underground Storage Tanks record under a tenth of a mile 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 Phoenix?
From about Nov 26 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 26 (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 26. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Phoenix's scale — its 9b band and its 345-day season. Your yard writes its own version of Phoenix'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 Phoenix’s own scale
6 of the readings below were taken at Phoenix's own scale — the 331,728 acres it covers and 3,933 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Phoenix's own USDA hardiness band, zones 9bUSDA PHZM 2023
- 3,933 documented contamination sites on the federal record near Phoenix, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Phoenix's boundary and the 331,728 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9b and a ~345-day seasonGrowable Ground crop-matching engine
- The ecoregion at Phoenix's own centroid, the Sonoran Basin and RangeUS EPA Level III Ecoregions
- Lanternfly survey cells around Phoenix checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- The 28°F hard-freeze dates — Phoenix has no normal of its own, so its county's is the closest measured readfrom Maricopa County
- Soil character — no town-scale survey exists, so Phoenix's 331,728 acres read through its county's SSURGO summaryfrom Maricopa County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Maricopa 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 Maricopa County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Phoenix's 331,728 acreswhy one lot differs from the next →
- Which side of Phoenix you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 331,728 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record under a tenth of a mile 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 Phoenix-wide figureread your own land →