Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 85123 — Arizona City, AZ

ZIP code 85123 (Arizona City, Pinal County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is February 28 and the first fall frost November 21.

Where ZIP 85123 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone9a20 to 25 °F
Coldest night−6.7 to −3.9 °C
Last frostFeb 28
First frostNov 21
2012 zone9a

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 9a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Arizona City, AZ…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Arizona City, AZ

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostFebruary 28median — 50% chance of a later frost
Safe for tender plantsMarch 14only 10% chance of frost after
First fall frostNovember 21median — 10% chance by Nov 5
Growing season266 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 6 and returns around December 4.

From the NOAA station Arizona City, AZ — within 1 mile, elevation 1,526 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 85123

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Jan 17 – Jan 31
SpinachSow outdoors · Jan 17 – Feb 7
Broccoli, cabbageStart indoors · Dec 20 – Jan 3
Broccoli, cabbageTransplant · Feb 7 – Feb 21
Onion setsPlant outdoors · Jan 31 – Feb 14
PotatoesPlant outdoors · Feb 7 – Feb 21
LettuceSow outdoors · Jan 31 – Feb 14
Carrots, beetsSow outdoors · Feb 7 – Feb 21
TomatoesStart indoors · Jan 3 – Jan 17
TomatoesTransplant · Mar 7 – Mar 21
Peppers, eggplantStart indoors · Dec 20 – Jan 3
Peppers, eggplantTransplant · Mar 14 – Mar 28
BeansSow outdoors · Mar 7 – Mar 21
Sweet cornSow outdoors · Mar 7 – Mar 21
Cucumbers, squashSow outdoors · Mar 7 – Mar 21
Fall lettuce, spinachSow outdoors · Sep 26 – Oct 10
GarlicPlant cloves · Nov 7 – Dec 12
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 28) and first fall frost (Nov 21) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 85123 came on Jan 27 — about the same time as the 1991–2020 average (Jan 27).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 9a in Arizona

492 plants native to the lower 48 states, recorded in Arizona, and rated by the USDA to survive 20 °F or colder — the bottom of zone 9a. Each links to its USDA PLANTS profile.

Trees 26

Arizona cypress50 ft · blooms spring · low shade tolerance · to −23 °FArizona madrone30 ft · blooms late spring · high shade tolerance · to −4 °FArizona sycamore80 ft · blooms early spring · high shade tolerance · to −8 °FArizona walnut50 ft · blooms late spring · high shade tolerance · to −33 °Fblack locust60 ft · blooms spring · high shade tolerance · to −37 °Fblue spruce100 ft · blooms late spring · medium shade tolerance · to −38 °F

Shrubs 109

alderleaf mountain mahogany15 ft · blooms late spring · medium shade tolerance · to −41 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °FAmerican tarwort3 ft · blooms late spring · high shade tolerance · to −23 °Fantelope bitterbrush6 ft · blooms early spring · medium shade tolerance · to −36 °FApache plume6 ft · blooms late spring · high shade tolerance · to −23 °Fbig sagebrush4 ft · blooms mid summer · high shade tolerance · to −43 °F

Wildflowers & perennials 197

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine mountainsorrel1 ft · blooms mid summer · medium shade tolerance · to −43 °FAmerican alpine speedwell1 ft · blooms summer · medium shade tolerance · to −28 °FAmerican bistort1.5 ft · blooms mid spring · high shade tolerance · to −38 °FAmerican century plant6 ft · blooms indeterminate · high shade tolerance · to 12 °F

Grasses 151

alkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Falkali sacaton3 ft · blooms mid summer · high shade tolerance · to −38 °Falpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °Fanalogue sedge1.5 ft · blooms late spring · medium shade tolerance · to −38 °FArizona cottontop4 ft · blooms late summer · high shade tolerance · to −13 °FArizona fescue2 ft · blooms late spring · high shade tolerance · to −23 °F

Vines 1

western white clematis1 ft · blooms mid summer · medium shade tolerance · to −38 °F

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Arizona City, AZ.

Soil in Arizona City, AZ

The soil mapped at the center of ZIP 85123 is Marana — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH8.2alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupCwater soaks in slowly
Farmland classPrime farmland if irrigated and either protected from flooding or not frequently flooded during the growing seasonUSDA classification

Map unit: Marana silty clay loam.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 85123; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Arizona City, AZ

Summer high104 °Faverage high, July
Winter low34 °Faverage low, January
Hot days173days a year at 90 °F or more
Freezing nights33nights a year at 32 °F or less
Growing degree days7,171base 50 °F — the season’s usable heat
Longest day14 h 18 mindaylight on June 21
Shortest day10 h 00 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation8 inper year, rain and melted snow

Average high and low, by month

20°30°40°50°60°70°80°90°100°110°32 °FJanuary: average high 64 °F, low 34 °F 64°34° JanFebruary: average high 69 °F, low 38 °F 69°38° FebMarch: average high 76 °F, low 43 °F 76°43° MarApril: average high 84 °F, low 49 °F 84°49° AprMay: average high 93 °F, low 58 °F 93°58° MayJune: average high 103 °F, low 67 °F 103°67° JunJuly: average high 104 °F, low 76 °F 104°76° JulAugust: average high 102 °F, low 75 °F 102°75° AugSeptember: average high 98 °F, low 68 °F 98°68° SepOctober: average high 88 °F, low 54 °F 88°54° OctNovember: average high 75 °F, low 41 °F 75°41° NovDecember: average high 64 °F, low 34 °F 64°34° Dec

Precipitation by month inches

0″1″2″January: 0.74 in precipitation 0.7 JanFebruary: 0.99 in precipitation 1.0 FebMarch: 0.94 in precipitation 0.9 MarApril: 0.11 in precipitation 0.1 AprMay: 0.22 in precipitation 0.2 MayJune: 0.10 in precipitation 0.1 JunJuly: 1.15 in precipitation 1.1 JulAugust: 1.09 in precipitation 1.1 AugSeptember: 0.96 in precipitation 1.0 SepOctober: 0.28 in precipitation 0.3 OctNovember: 0.43 in precipitation 0.4 NovDecember: 0.94 in precipitation 0.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Arizona City, AZ (within 1 mile); precipitation: Arizona City, AZ (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9a.

851319a
Eloy, AZ · 7 mi
851309a
Casa Grande, AZ · 7 mi
851939a
Casa Grande, AZ · 12 mi
851949a
Casa Grande, AZ · 13 mi
851229a
Casa Grande, AZ · 15 mi
851419a
Picacho, AZ · 15 mi
851289a
Coolidge, AZ · 20 mi
851459a
Red Rock, AZ · 21 mi

Arizona planting zones →

Questions about 85123

What planting zone is ZIP code 85123?

ZIP code 85123 (Arizona City, AZ) is in USDA hardiness zone 9a on the 2023 map: the coldest night of an average winter reaches 20 to 25 °F (−6.7 to −3.9 °C).

When is the last frost in Arizona City, AZ?

The median last spring frost (32 °F) near 85123 is February 28; after March 14 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Arizona City station.

When is the first frost in Arizona City, AZ?

The median first fall frost near 85123 is November 21, giving a median frost-free growing season of 266 days.

When should I plant tomatoes in 85123?

Start tomato seeds indoors around Jan 3 – Jan 17 and set transplants outside around Mar 7 – Mar 21, one to three weeks after the median last frost.

How much rain and snow does 85123 get?

About 8 inches of precipitation a year (NOAA 1991–2020 normals, Arizona City station).

How hot do summers get in Arizona City, AZ?

The average high peaks at 104 °F in July, with about 173 days a year at 90 °F or more.

What kind of soil does 85123 have?

The USDA soil survey maps Marana at the center of ZIP 85123: silty clay loam, well drained, pH about 8.2 (alkaline).

Did spring come early in Arizona City, AZ in 2026?

Spring leaf-out near 85123 came on Jan 27 in 2026, about the same as the 1991–2020 average (Jan 27), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Arizona City, AZ?

Intermediate onions: the longest day near 85123 is 14 h 18 min, so day-neutral types bulb best; long-day varieties may not bulb fully.