Maricopa, Arizona, sits in USDA hardiness zone 9a — a zone band wide enough that plant choice, not possibility, is the interesting question.
A short list that earns its place here — jalapeno, palo verde, date palm, and prickly pear — with any one site's soil, sun, and drainage making the final cut.
Even in Maricopa, 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 Maricopa 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 Maricopa — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Maricopa — the short answer
Maricopa, Arizona: USDA zone 9a, about 327 days between hard freezes, across 27K acres of city.
- USDA zone
- 9a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Jan 23
- Pinal County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 16
- Pinal County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~327
- Pinal County normal — NOAA 1991–2020, nearest to this town
- City area
- 27K 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 Pinal County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9a is Maricopa's average, not your lot's — a low corner or a tree line moves it. Against Maricopa's 327-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Maricopa
Each reading below is measured for Maricopa itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsMaricopa runs about 327 days between hard freezes (read from Pinal County, the closest normal to Maricopa) — 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
MeasuredMaricopa 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 Maricopa is in
Maricopa sits in the Sonoran Basin and Range — EPA Level III, inside the wider North American Deserts. That is read at Maricopa's own centroid rather than borrowed from Pinal County.
What Grows in Maricopa
Plants matched to Maricopa's USDA zones 9a, ordered by how much hardiness margin each has here — the ones with room to spare at both ends of this town's band lead. Each links to its full growing profile.
Is it too late to plant in Maricopa?
Rarely: the season closes in stages, not all at once, and each stage has its crops. 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 23 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 16 — 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.
Documented around Maricopa
Survey cells within 31 miles of Maricopa checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 300 miles off. What to watch for.
What's on the federal record near Maricopa
Closest first, within ~10 miles of Maricopa. Listing isn't leaking, and distance isn't exposure.
- WALMART SUPERCENTER #4430Brownfields · 0.9 mi
- D-04-03 35DDDNitrate · 1.2 mi
- CIRCLE K STOREUnderground Storage Tanks · 1.4 mi
- MARICOPA FEEDYARD - WESTUnderground Storage Tanks · 1.5 mi
- D-05-03 01DAD1Nitrate · 1.6 mi
- GWR - SANTA CRUZ WATER CO. INC.PFAS · 1.7 mi
- MARICOPA CATTLE CO.Nitrate · 1.9 mi
- PINAL ENERGYToxics Release Inventory · 2.1 mi
- THE SCOTTS COMPANY LLCBrownfields · 2.4 mi
- MARICOPA AGRICULTURAL CENTERBrownfields · 2.5 mi
- D-04-04 17CDDNitrate · 2.7 mi
- MARICOPA AGRICULTURAL CENTERUnderground Storage Tanks · 2.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Maricopa'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 Maricopa.
Total Sites
103
within ~10 miles of Maricopa
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Maricopa
Severity Distribution
within ~10 miles of Maricopa
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Maricopa, Nitrate runs higher than the national average — 58 sites within ~10 miles of Maricopa. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Maricopa
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 Maricopa average
Your land is one point inside Maricopa
Everything above resolves to Maricopa as a whole — one PHZM band, read across 27K acres, with hard-freeze dates borrowed from Pinal 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 Maricopa Average
Maricopa Average
- ●USDA Zones 9a, averaged across Maricopa
- ●One soil character for all of Maricopa
- ●Frost dates read at Maricopa's scale: Jan 23 to Dec 16
YOUR Parcel
- ✓Your exact zone, not Maricopa's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Maricopa
Pull a site-specific report for your exact address in Maricopa, Arizona — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Maricopa averages can't show:
We read public map data around Maricopa — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Maricopa average
How we know this about Maricopa
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 Pinal 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 Maricopa
When does frost risk typically end in Maricopa?
The last hard freeze (28°F) in Maricopa typically lands around Jan 23, 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 13.
When is the first frost in Maricopa?
The first hard freeze (28°F) in Maricopa typically arrives around Dec 16, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Dec 2, so the watching starts about Nov 16 — about 327 days after the spring freeze cleared.
How long is the growing season in Maricopa?
Measured between 28°F hard freezes, Maricopa sees about 327 frost-free days — roughly Jan 23 through Dec 16, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 13 to Dec 2, about 292 days.
Is the soil safe to grow vegetables in Maricopa?
The federal record around Maricopa is a meaningful one — 103 documented sites, mostly Nitrate entries (58), the nearest Brownfields record about 0.9 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 Maricopa?
From about Nov 16 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 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 Dec 16. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Maricopa's scale — its 9a band and its 327-day season. Your yard writes its own version of Maricopa'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 Maricopa’s own scale
5 of the readings below were taken at Maricopa's own scale — the 27,190 acres it covers and 103 documented sites around it; 6 are borrowed from a wider read, named and linked below.
Measured here
- Maricopa's own USDA hardiness band, zones 9aUSDA PHZM 2023
- 103 documented contamination sites on the federal record near Maricopa, the closest Brownfields record about 0.9 miles out from the town centreFederal environmental registers
- Maricopa's boundary and the 27,190 acres inside itUS Census TIGER/Line 2025
- The ecoregion at Maricopa's own centroid, the Sonoran Basin and RangeUS EPA Level III Ecoregions
- Lanternfly survey cells around Maricopa checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- The 28°F hard-freeze dates — Maricopa has no normal of its own, so its county's is the closest measured readfrom Pinal County
- Soil character — no town-scale survey exists, so Maricopa's 27,190 acres read through its county's SSURGO summaryfrom Pinal County
- The candidate plant list — Arizona's curated set, filtered to this zone band and re-ordered by how much margin each has herefrom Arizona
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Pinal 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 Pinal County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Maricopa's 27,190 acreswhy one lot differs from the next →
- Which side of Maricopa you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 27,190 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.9 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 Maricopa-wide figureread your own land →