South Tucson, Arizona, sits in USDA hardiness zone 9b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Among the crops suited to this profile: jalapeno, palo verde, date palm, and prickly pear. The site-level story — soil, sun, drainage — decides the rest.
Even in South Tucson, 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 South Tucson 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 South Tucson — soil, climate, flood, and parcel records. How we handle your address.
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South Tucson — the short answer
South Tucson, Arizona: USDA zone 9b, about 313 days between hard freezes, across 657 acres of city.
- USDA zone
- 9b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 3
- Pima County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 13
- Pima County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~313
- Pima County normal — NOAA 1991–2020, nearest to this town
- City area
- 657 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 Pima County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9b is South Tucson's average, not your lot's — a low corner or a tree line moves it. Against South Tucson's 313-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in South Tucson
Each reading below is measured for South Tucson itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsSouth Tucson runs about 313 days between hard freezes (read from Pima County, the closest normal to South Tucson) — 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
MeasuredSouth Tucson 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 South Tucson is in
South Tucson sits in the Sonoran Basin and Range — EPA Level III, inside the wider North American Deserts. That is read at South Tucson's own centroid rather than borrowed from Pima County.
What Grows in South Tucson
Plants matched to South Tucson's USDA zones 9b, 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 South Tucson?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Jan 6; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 3 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 13 — long-season crops need about 90 days of runway, quick greens only 30. Here the calendar nearly circles: cool-season crops take the winter shift, and the next window is always close.
Documented around South Tucson
Survey cells within 31 miles of South Tucson checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 367 miles off. What to watch for.
What's on the federal record near South Tucson
Closest first, within ~10 miles of South Tucson. Listing isn't leaking, and distance isn't exposure.
- VACANTUnderground Storage Tanks · 650 ft
- FAMILY DOLLAR #4948Brownfields · 700 ft
- CHEVRON - SIGNAL BULK PLANTUnderground Storage Tanks · 950 ft
- CIRCLE K #2701581Underground Storage Tanks · 1000 ft
- WALGREEN #3377Brownfields · 1300 ft
- BEST RADIATOR & REPAIR SERVICEUnderground Storage Tanks · 1400 ft
- CUTTING EDGE COLLISION CENTERUnderground Storage Tanks · 1600 ft
- ARIZONA CHILDREN'S HOMEUnderground Storage Tanks · 1700 ft
- CVS PHARMACY #AZTUC3B01Brownfields · 1700 ft
- CITY OF SOUTH TUCSON - GOVERNMENT COMPLEXUnderground Storage Tanks · 1700 ft
- REUTER PROPERTYUnderground Storage Tanks · 1900 ft
- SALVATION ARMY - ADULT REHABILITATION CENTERUnderground Storage Tanks · 1900 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from South Tucson'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 South Tucson.
Sources Checked
within ~10 miles of South Tucson
Severity Distribution
within ~10 miles of South Tucson
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around South Tucson, Nitrate runs higher than the national average — 738 sites within ~10 miles of South Tucson. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
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 South Tucson
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 South Tucson average
Your land is one point inside South Tucson
Everything above resolves to South Tucson as a whole — one PHZM band, read across 657 acres, with hard-freeze dates borrowed from Pima 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 South Tucson Average
South Tucson Average
- ●USDA Zones 9b, averaged across South Tucson
- ●One soil character for all of South Tucson
- ●Frost dates read at South Tucson's scale: Feb 3 to Dec 13
YOUR Parcel
- ✓Your exact zone, not South Tucson's 9b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in South Tucson
Pull a site-specific report for your exact address in South Tucson, Arizona — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that South Tucson averages can't show:
We read public map data around South Tucson — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the South Tucson average
How we know this about South Tucson
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 Pima 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 South Tucson
When does frost risk typically end in South Tucson?
The last hard freeze (28°F) in South Tucson typically lands around Feb 3, 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 24.
When is the first frost in South Tucson?
The first hard freeze (28°F) in South Tucson typically arrives around Dec 13, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 29, so the watching starts about Nov 13 — about 313 days after the spring freeze cleared.
How long is the growing season in South Tucson?
Measured between 28°F hard freezes, South Tucson sees about 313 frost-free days — roughly Feb 3 through Dec 13, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Feb 24 to Nov 29, about 278 days.
Is the soil safe to grow vegetables in South Tucson?
The federal record around South Tucson runs heavier than most — 2,496 documented sites, mostly Underground Storage Tanks entries (1,202), the nearest Underground Storage Tanks record about 0.1 miles out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
How do I protect my plants from frost in South Tucson?
From about Nov 13 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 13 (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 13. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at South Tucson's scale — its 9b band and its 313-day season. Your yard writes its own version of South Tucson'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 South Tucson’s own scale
5 of the readings below were taken at South Tucson's own scale — the 657 acres it covers and 2,496 documented sites around it; 6 are borrowed from a wider read, named and linked below.
Measured here
- South Tucson's own USDA hardiness band, zones 9bUSDA PHZM 2023
- 2,496 documented contamination sites on the federal record near South Tucson, the closest Underground Storage Tanks record about 0.1 miles out from the town centreFederal environmental registers
- South Tucson's boundary and the 657 acres inside itUS Census TIGER/Line 2025
- The ecoregion at South Tucson's own centroid, the Sonoran Basin and RangeUS EPA Level III Ecoregions
- Lanternfly survey cells around South Tucson checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- The 28°F hard-freeze dates — South Tucson has no normal of its own, so its county's is the closest measured readfrom Pima County
- Soil character — no town-scale survey exists, so South Tucson's 657 acres read through its county's SSURGO summaryfrom Pima 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 Pima 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 Pima County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among South Tucson's 657 acreswhy one lot differs from the next →
- Which side of South Tucson you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 657 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.1 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 South Tucson-wide figureread your own land →