Sonoita / Elgin spans USDA hardiness zones 8a-9a — a zone band wide enough that plant choice, not possibility, is the interesting question.
Defined by the TTB's Sonoita American Viticultural Area (27 CFR § 9.97) — Arizona's first AVA, established in 1984 — this high-desert grassland spans Cochise, Pima, and Santa Cruz counties across USDA zones 8a to 9a, where the frost-free season runs roughly 264 to 313 days. Among the crops suited to this profile: jalapeno, prickly pear, palo verde, and date palm. The site-level story — soil, sun, drainage — decides the rest.
Sonoita / Elgin spans Arizona.
Your yard isn't all of Sonoita / Elgin.
Sonoita / Elgin spans USDA zones 8a-9a, but your parcel sits in exactly one — and slope, tree cover, and low spots nudge it further. 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 Sonoita / Elgin — soil, climate, flood, and parcel records. How we handle your address.
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Sonoita / Elgin — the short answer
Sonoita / Elgin: USDA zones 8a-9a, 264–313 frost-free days depending where in it you stand, in Arizona.
- USDA zones
- 8a-9a
- USDA PHZM 2023, aggregated over the footprint
- Shortest season here
- 264 days
- NOAA Regional Climate Centers ACIS, 1991-2020 — Cochise County
- Counties
- 3
- US Census TIGER/Line 2025
- Region type
- County cluster
- Growable Ground growing-region registry
Region boundary: Growable Ground growing-region registry — curated county clusters, EPA Level III ecoregions, and town clusters drawn finer than any county. The season figure is this region's own record, measured across its 3 member counties, not a state or national average.
Hardiness Zone Range
Sonoita / Elgin is not one growing season
One answer for Sonoita / Elgin averages 3 counties whose growing seasons are 49 days apart — from 264 frost-free days in Cochise County to 313 in Pima County. That is the same region, measured the same way, in the same years. Which end of it your land sits nearer decides what finishes before the first hard freeze.
The middle half of 3 counties runs 271–295 days, with a median of 277 days — a 49-day span end to end.
Measured across 3 member counties, each carrying its own 28°F normal. NOAA Regional Climate Centers ACIS, 1991-2020. A member with no own record is absent from the range rather than counted as zero — nothing here is interpolated to the region. Your own site sits somewhere inside this range; a parcel report resolves where.
Where the line runs inside Sonoita / Elgin
The middle half of Sonoita / Elgin runs 271–295 frost-free days, and 2 of its 3 counties sit outside that — 1 on the short side, 1 on the long. A regional planting date describes the middle well and the ends poorly, which is worth knowing before you follow one.
Under 271 frost-free days
1 county
- Cochise County · 264 days
The end of the region that sets the planting calendar — start seed indoors here and the season stretches to meet the crop.
271–295 frost-free days
1 county
0 of 1 shown
The middle half of the region, and the part a single regional season describes well.
Over 295 frost-free days
1 county
- Pima County · 313 days
Long enough for a second succession of a quick crop after the first comes out.
Each county is placed by its OWN 28°F frost-free normal (NOAA Regional Climate Centers ACIS, 1991-2020), the same figure its own guide page publishes. Elevation, slope and cold-air drainage move a site within its county as well — which is the part only your address resolves.
What Grows in Sonoita / Elgin
All 1 of the plants below that publish a season requirement clear even Cochise County’s 264 frost-free days — so on season alone, this grid works at both ends of the region. The 49-day spread still decides how far past this list you can push, and how early you can start.
Plants matched to Sonoita / Elgin's USDA zones 8a-9a, ordered by how much hardiness margin each has across the region — the ones with room to spare at both ends of this band lead. Each links to its full growing profile.
Native Plants of Sonoita / Elgin
Plants the USDA PLANTS Database documents as native and present in this region’s state, kept only where the published hardiness range meets Sonoita / Elgin’s USDA zones 8a-9a — closest range match first. Presence is recorded by state, so a plant can be documented across the state and still be scarce in your corner of the region.
The ground across Sonoita / Elgin
The USDA soil survey maps this ground county by county. These are those records weighted by land area across two member counties — this region’s own profile, not a state figure.
The ground is predominantly Aridisols, at 71% of mapped acres, followed by Entisols (19%), Mollisols (7%) and Vertisols (2%). Six soil orders appear somewhere inside the footprint, which is the honest reason a regional soil answer only goes so far. The most extensive named soils are Mohall, Hayhook, and Bucklebar.
89% of those acres are well drained, and another 6% somewhat excessively drained, 1% excessively drained. Topsoil pH runs 7.0–7.9 between the lowest and the highest county on record.
Soil order
Aridisols
Drainage
Well drained
Topsoil pH
7.0–7.9
Hydric soils
0%
Soil changes across a driveway, so which of these your own ground sits on is a parcel question rather than a regional one. Cochise County holds the most wetland ground here, at 1% — soil types explained.
USDA NRCS SSURGO via Soil Data Access · 2 of 3 footprint counties carry a summarizable record; the rest are absent from these figures rather than estimated.
What this means for growing in Sonoita / Elgin
The soil survey reads this ground county by county, and the readings above are those records summed across Sonoita / Elgin. Here is what they mean for a garden here — and the move an experienced grower makes about each one.
Drainage
From county records89% of the mapped acres across Sonoita / Elgin are well drained — ground that drains quickly. That is area-weighted across all two of its mapped counties.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
From county recordsTopsoil across Sonoita / Elgin runs pH 7.0–7.9 — alkaline in all two of them.
Many vegetables cope, but acid-lovers like blueberries struggle, and iron and manganese lock up above about pH 7.5 — leaves yellow between the veins even in rich soil.
Elemental sulfur and generous organic matter lower pH slowly for the beds that need it; test first so you add only what the soil actually calls for.
USDA NRCS SSURGO
Safe to Grow Here?
What the federal record shows across Sonoita / Elgin — and how to grow with it.
Across Sonoita / Elgin's 3 counties the federal record holds 7,561 documented sites, mostly Mining (2,479), Nitrate (2,368) and Underground Storage Tanks (1,899). The heaviest single county is Pima County, with 5,043.
That is a regional count, not a reading of any one lot — proximity to a documented site is information, not a diagnosis. Open the map outlined to Sonoita / Elgin to see which records sit where you actually grow.
Sources Checked
Summed across the 3 counties in Sonoita / Elgin
A note from Gnorman
What an experienced grower watches for around here
In and around Sonoita / Elgin, two things run higher than the national average across the 3 counties in Sonoita / Elgin — Mining (2,479 sites) and Nitrate (2,368 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).
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
Your land is one point inside Sonoita / Elgin
Everything above resolves to Sonoita / Elgin as a whole — a footprint whose own counties record seasons 49 days apart, and hardiness across zones 8a-9a. Your parcel sits at one point in that range, not in the middle of it. 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 region 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 regional average.
Your Lot vs Sonoita / Elgin Average
Sonoita / Elgin Average
- ●USDA Zones 8a-9a, averaged across Sonoita / Elgin
- ●One soil character for all of Sonoita / Elgin
- ●State-average frost dates
YOUR Parcel
- ✓Your exact zone, not Sonoita / Elgin's 8a-9a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Sonoita / Elgin
Pull a site-specific report for your exact address in Sonoita / Elgin — soil, sun, drainage, frost risk, contamination, and scored plant recommendations.
Three things about your lot that Sonoita / Elgin averages can't show:
We read public map data around Sonoita / Elgin — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not Sonoita / Elgin average
How we know this about Sonoita / Elgin
The boundary: a cluster of neighboring counties. Growing regions have no official boundary, so this footprint is our published one, and every figure on this page was measured over the counties inside it rather than borrowed from the state around it.
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, aggregated across the footprint; the growing season from NOAA Regional Climate Centers ACIS 1991–2020 28°F normals, read at each member’s own record; boundaries from US Census TIGER/Line 2025; the contamination record from the federal sources named in that beat above; the soil from the USDA NRCS SSURGO survey, read at each member county’s own record and weighted to this footprint by land area. Where a member carries no record of its own, it is absent from the figure rather than filled in.
Common questions about Sonoita / Elgin
What hardiness zone is Sonoita / Elgin?
Sonoita / Elgin spans USDA hardiness zones 8a-9a, aggregated from the USDA Agricultural Research Service Plant Hardiness Zone Map 2023 across the region's counties. Zones reflect average annual extreme minimum temperatures from 1991–2020 data.
How long is the growing season in Sonoita / Elgin?
Measured between 28°F hard freezes, Sonoita / Elgin's counties mostly run 271 to 295 frost-free days, median 277 (NOAA Regional Climate Centers ACIS, 1991–2020, over 3 member counties). That 24-day spread is the honest read — no single season describes 3 counties, and each county guide below carries its own.
When does frost risk end in Sonoita / Elgin?
Across Sonoita / Elgin, the middle half of member counties see their last 28°F hard freeze between Feb 14 and Mar 1 (median Feb 25), and their first fall freeze between Nov 27 and Dec 6. Those are hard freezes, not the last light frost: tender transplants wait for about Mar 18, and elevation decides which end of a 15-day spread you garden in.
What grows well in Sonoita / Elgin?
Sonoita / Elgin's conditions suit plants such as Jalapeno, Prickly Pear, Palo Verde, Date Palm, Citrus. What actually thrives on any one site still turns on its specific soil, sun, and drainage — we score each plant against the real conditions at your address.
How is Sonoita / Elgin defined?
Sonoita / Elgin is defined here as a curated cluster of 3 neighboring counties that share a growing character. Growing regions have no official boundary, so this footprint is our published one — every county in it is named on this page.
Which states does Sonoita / Elgin cover?
Sonoita / Elgin spans Arizona. Each state's full growing guide is linked on this page.
What other growing regions cover the same states?
Sonoran Desert, Lower Colorado River Corridor, White Mountains (Eastern Arizona), Willcox AVA, Flagstaff & San Francisco Peaks High Country, and Mogollon Rim Country (Payson) share at least one state with Sonoita / Elgin. Growing regions overlap and interlock — a single address can sit inside more than one, which is why the precise read is always the parcel, not the region.
What this page reads at Sonoita / Elgin’s own scale
6 of the readings below were taken at Sonoita / Elgin's own scale — the zone 8a-9a band across its footprint, a median 277-day season across its 3 counties and 7,561 documented federal contamination records across its 3 counties, 5,043 of them in Pima County alone; one is borrowed from a wider read, named and linked below.
Measured here
- The USDA hardiness band 8a-9a aggregated across all 3 counties in the footprintUSDA PHZM 2023
- The boundary itself — the 3 counties this region is curated fromGrowable Ground subregion registry
- The growing character that makes this region distinct from the states it crossesGrowable Ground subregion registry
- The 28°F season across the footprint — the middle half of its 3 counties run 271 to 295 frost-free days, median 277NOAA Regional Climate Centers ACIS, 1991-2020
- The federal contamination record over the whole footprint — 7,561 documented federal contamination records across its 3 counties, 5,043 of them in Pima County aloneEPA, USGS and USDA federal site records
- The soil order mix across the footprint — 71% Aridisols, topsoil pH 7.0–7.9, area-weighted across its 2 mapped countiesUSDA NRCS SSURGO
Inherited from a wider read
- The candidate plant list — its state's curated sets, merged and filtered to zones 8a-9afrom Arizona
What this page can’t tell you
- Which end of the 24-day range your ground sits at — 271 days at one extreme, 295 at the other, decided mostly by elevationfrost dates explained →
- Which of those soils your own ground sits on — the survey maps them county-wide, and they change across a drivewaysoil types explained →
- The soil pH, drainage, sun hours, and frost pockets on one specific lotwhy one lot differs from the next →
Explore Sonoita / Elgin
State growing guides
Counties in this region
Other growing regions across Arizona
A warm desert of saguaro and palo verde with mild winters that allow desert citrus, dates, and prickly pear alongside intensive irrigated gardening.
The river towns from Bullhead City to Parker — essentially frost-free 9a-10a bottomland where citrus and winter gardens run while the Mohave high desert a half-hour up the grade freezes.
Arizona's high green country — at the White Mountain towns the committed record reads 6a-7a with a 145-176-day season, mountain gardening closer to Colorado than to the desert two hours down the hill.
Established by the TTB in 2016 across parts of Cochise and Graham Counties in southeastern Arizona, the Willcox AVA spans USDA hardiness zones 8a to 8b with a roughly 264-to-266-day frost-free season.
The cold antithesis of desert Arizona: a ponderosa-pine plateau near 7,000 ft where Flagstaff sits in USDA zone 6a and Bellemont drops to 5b, with only about 150 frost-free days — roughly mid-May last frost to mid-October first frost (Coconino County, api/data/county_data.json). The statewide "zone 9b, near-frost-free" framing is actively wrong here; growers plan around snow, a short cool-season window, and hard frost dates instead of citrus and dates.
Payson's mid-elevation shelf under the Mogollon Rim — real winter frost and a 7b-8a, 214-237-day season that splits the difference between the low desert's heat and the Rim top's snow; pine-country gardening with monsoon summers.