Tonto Basin, Arizona, sits in USDA hardiness zone 9a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
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 Tonto Basin, 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 Tonto Basin 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 Tonto Basin — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Tonto Basin — the short answer
Tonto Basin, Arizona: USDA zone 9a, about 295 days between hard freezes, across 21K acres of town.
- USDA zone
- 9a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Feb 12
- Gila County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Dec 4
- Gila County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~295
- Gila County normal — NOAA 1991–2020, nearest to this town
- Town area
- 21K 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 Gila County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 9a is Tonto Basin's average, not your lot's — a low corner or a tree line moves it. Against Tonto Basin's 295-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Tonto Basin
Each reading below is measured for Tonto Basin itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsTonto Basin runs about 295 days between hard freezes (read from Gila County, the closest normal to Tonto Basin) — 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
MeasuredTonto Basin 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 Tonto Basin is in
Tonto Basin sits in the Sonoran Basin and Range — EPA Level III, inside the wider North American Deserts. That is read at Tonto Basin's own centroid, and it is not what its county reads: Gila County is mostly Arizona/New Mexico Mountains. The wider page above you is answering a different question about different ground.
What Grows in Tonto Basin
Every plant below cleared Tonto Basin's own zone 9a and its 295-day season. Each card opens that plant's Arizona profile. How we score.
Is it too late to plant in Tonto Basin?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Jan 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Feb 12 (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. Here the calendar nearly circles: cool-season crops take the winter shift, and the next window is always close.
Documented around Tonto Basin
Survey cells within 31 miles of Tonto Basin checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 342 miles off. What to watch for.
What's on the federal record near Tonto Basin
Closest first, within ~10 miles of Tonto Basin. Listing isn't leaking, and distance isn't exposure.
- A-06-10 26ABA2Nitrate · 1400 ft
- TONTO BASIN MARKETPLACEUnderground Storage Tanks · 1.0 mi
- BUTCHERS HOOK RESTAURANTUnderground Storage Tanks · 1.2 mi
- ADOT - PUNKIN CENTER MAINTENANCEUnderground Storage Tanks · 1.8 mi
- USDA FS - TONTO BASIN WORK CENTERUnderground Storage Tanks · 1.9 mi
- A-06-10 11CCDNitrate · 2.0 mi
- A-06-10 36DBANitrate · 2.0 mi
- TONTO BASIN AUTO PARTS & GARAGEUnderground Storage Tanks · 2.4 mi
- A-06-11 31DCB4Nitrate · 2.7 mi
- AT&T - TONTO BASINUnderground Storage Tanks · 4.5 mi
- A-07-10 23CDCNitrate · 6.0 mi
- HumdingerMining · 6.1 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Tonto Basin'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 Tonto Basin.
Sources Checked
within ~10 miles of Tonto Basin
Severity Distribution
within ~10 miles of Tonto Basin
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Tonto Basin, two things run higher than the national average within ~10 miles of Tonto Basin — Mining (11 sites) and Nitrate (14 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.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Tonto Basin
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 Tonto Basin average
Your land is one point inside Tonto Basin
Everything above resolves to Tonto Basin as a whole — one PHZM band, read across 21K acres, with hard-freeze dates borrowed from Gila 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 Tonto Basin Average
Tonto Basin Average
- ●USDA Zones 9a, averaged across Tonto Basin
- ●One soil character for all of Tonto Basin
- ●Frost dates read at Tonto Basin's scale: Feb 12 to Dec 4
YOUR Parcel
- ✓Your exact zone, not Tonto Basin's 9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Tonto Basin
Pull a site-specific report for your exact address in Tonto Basin, Arizona — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Tonto Basin averages can't show:
We read public map data around Tonto Basin — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Tonto Basin average
How we know this about Tonto Basin
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 Gila 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 Tonto Basin
When does frost risk typically end in Tonto Basin?
The last hard freeze (28°F) in Tonto Basin typically lands around Feb 12, 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 5.
When is the first frost in Tonto Basin?
The first hard freeze (28°F) in Tonto Basin 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 295 days after the spring freeze cleared.
How long is the growing season in Tonto Basin?
Measured between 28°F hard freezes, Tonto Basin sees about 295 frost-free days — roughly Feb 12 through Dec 4, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 5 to Nov 20, about 260 days.
Is the soil safe to grow vegetables in Tonto Basin?
The federal record around Tonto Basin is a meaningful one — 32 documented sites, mostly Nitrate entries (14), the nearest Nitrate record about 0.3 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 Tonto Basin?
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 Tonto Basin's scale — its 9a band and its 295-day season. Your yard writes its own version of Tonto Basin'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 Tonto Basin’s own scale
6 of the readings below were taken at Tonto Basin's own scale — the 20,557 acres it covers and 32 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Tonto Basin's own USDA hardiness band, zones 9aUSDA PHZM 2023
- 32 documented contamination sites on the federal record near Tonto Basin, the closest Nitrate record about 0.3 miles out from the town centreFederal environmental registers
- Tonto Basin's boundary and the 20,557 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 9a and a ~295-day seasonGrowable Ground crop-matching engine
- Tonto Basin sits in the Sonoran Basin and Range — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
- Lanternfly survey cells around Tonto Basin checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- The 28°F hard-freeze dates — Tonto Basin has no normal of its own, so its county's is the closest measured readfrom Gila County
- Soil character — no town-scale survey exists, so Tonto Basin's 20,557 acres read through its county's SSURGO summaryfrom Gila County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Gila 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 Gila County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Tonto Basin's 20,557 acreswhy one lot differs from the next →
- Which side of Tonto Basin you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 20,557 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 0.3 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 Tonto Basin-wide figureread your own land →
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