Graham County, in Arizona, sits in USDA hardiness zone 8b — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
Expect palo verde, jalapeno, date palm, and prickly pear to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Graham County holds more than one microclimate.
Soils and elevations shift across Graham County, so your frost dates and drainage aren't the county average. Enter your address and we'll score 1,112 plants against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
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Quick Facts
USDA Zones
8b
Last Hard Freeze (28°F)
Jan 18
County normal — light frosts run a few weeks later
First Hard Freeze (28°F)
Dec 10
County normal — light frosts arrive a few weeks earlier
County Area
3.0M acres
Hardiness Zone Range
Zone maps are averages across Graham County. Your yard's slope, trees, and frost pockets shift what actually grows — see your land's exact reading.
Soil in Graham County
Across Graham County, the ground is predominantly Aridisols, where Tubac, Tres Hermanos, and Beaumain are the most extensive named soil series. The soil is generally well drained with a gravelly sandy loam surface. Topsoil pH runs about 6.7–7.9, neutral. Rainfall drains through hydrologic group D soils.
Soil order
Aridisols
Drainage
Well drained
Hydric soils
0%
Soil still varies lot by lot — soil types explained.
What Grows in Graham County
Plants matched to Graham County's USDA zones 8b — each links to its full growing profile.
Is it too late to plant in Graham County?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. 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 18 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 10 — long-season crops need about 90 days of runway, quick greens only 30. In a climate this gentle, “too late” hardly applies — the question becomes which crops prefer the cooler months ahead.
Growing Challenges in Arizona
What an experienced grower plans around here — each one has a move.
Extreme heat exceeding 110F stresses most plants
Desert gardens run on winter: plant to the October-March windows and give the summer holdouts afternoon shade.
Minimal rainfall requires drip irrigation
Drip plus a deep mulch layer is the desert baseline — it waters roots, not air, and cuts evaporation dramatically.
Caliche hardpan prevents root penetration without breaking through
Where caliche won't break, build up instead — a deep raised bed gives roots the depth the ground refuses.
For cultivar selection, pest pressure, and planting-time guidance specific to Arizona, the University of Arizona Cooperative Extension is the authoritative local source.
Safe to Grow Here?
What the federal record shows across Graham County — and how to grow with it.
We checked the federal record across Graham County — 503 documented sites across 7 of the 9 source types we track.
The most significant on record: 2 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Graham County carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds with clean imported soil grow well almost anywhere in the meantime.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
Environmental Intelligence
Understanding what's nearby helps you make informed decisions about where and how to grow.
Sources Checked
across Graham County
Severity Distribution
across Graham County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Graham County, two things run higher than the national average — Mining (224 sites) and Nitrate (158 sites). That's not a problem with your land — it's information about 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 Graham County
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,112 plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Your Specific Parcel Matters
Graham County Average
- ●USDA Zones 8b
- ●Generic soil type for the area
- ●State-average frost dates
YOUR Parcel
- ✓Your exact hardiness zone
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Graham County
Pull a site-specific report for your exact address in Graham County, Arizona — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Key Growing Facts for Graham County, Arizona
- USDA Hardiness Zones: 8b (USDA PHZM 2023)
- Last Hard Freeze (28°F): Jan 18 (county normal, NOAA 1991–2020 Climate Normals — light frosts can follow for a few weeks)
- First Hard Freeze (28°F): Dec 10 (county normal, NOAA 1991–2020 Climate Normals — light frosts can arrive a few weeks earlier)
- Days Between Hard Freezes: ~326 (county normal, NOAA 1991–2020 Climate Normals)
- County Land Area: 3.0M acres (US Census TIGER 2025)
Zone data: USDA ARS Plant Hardiness Zone Map 2023. Climate data: NOAA NCEI. County boundaries: US Census TIGER/Line 2025.
Frost dates here are the Graham County average. Low spots and tree cover move them by days on any one yard — see your exact frost windows.
Frequently Asked Questions
What hardiness zone is Graham County, Arizona?
Graham County sits in USDA hardiness zone 8b, per the USDA Plant Hardiness Zone Map 2023. Zones reflect average annual extreme minimum temperatures from 1991–2020 weather data.
Is it too late to plant in Graham County?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. 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 18 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 10 — long-season crops need about 90 days of runway, quick greens only 30. In a climate this gentle, “too late” hardly applies — the question becomes which crops prefer the cooler months ahead.
When does frost risk typically end in Graham County?
The last hard freeze (28°F) in Graham County typically lands around Jan 18, per NOAA 1991–2020 climate normals — an earlier marker than the light-frost dates many planting charts quote. That marks the hard freeze, not the last light frost — light frosts can still bite for a few more weeks, so tender transplants usually wait another 2–3 weeks.
How long is the growing season in Graham County?
Measured between 28°F hard freezes, Graham County sees about 326 frost-free days — roughly Jan 18 through Dec 10, per NOAA 1991–2020 climate normals. Tender crops get a somewhat shorter practical window, since lighter frosts reach a few weeks past the hard-freeze dates on both ends.
What vegetables grow in Graham County?
Graham County's zone 8b supports a wide range — strong performers include Palo Verde, Jalapeno, Date Palm, and Prickly Pear. What actually takes on any one site comes down to its soil, sun, and drainage, and we score each plant against the real conditions at your address.
Which hardiness zone is Graham County, really?
Officially, Graham County sits in USDA zone 8b (USDA PHZM 2023) — but a zone is a 30-year average of winter's coldest night across an area, and it can't see any one yard. A south-facing slope, a tree line, or a low frost pocket can shift a single site by half a zone either way, which is why neighboring gardeners often quote different numbers. We read the conditions at your exact address — soil, sun, slope, and frost — and score 1,112 plants against what's actually there.
Is the soil safe to grow vegetables in Graham County?
The federal record around Graham County runs heavier than most — 503 documented sites — 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.
Just moved to Graham County — what should I know before planting?
Start with three facts. Graham County sits in USDA zone 8b, which sets what survives winter; the last 28°F hard freeze typically clears around Jan 18, with about 326 frost-free days to work with (NOAA 1991–2020 climate normals); and 503 documented sites sit on the federal record here, so a soil test before food beds is the smart first step. From there, matching plants to your actual soil and sun is the fun part.
Everything on this page is a Graham County average. Your yard writes its own version — we read soil, sun, drainage, and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads Arizona's frost window, season length, and soil profile against the plant's real requirements.