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

Planting zone for 85750 — Tucson, AZ

ZIP code 85750 (Tucson, Pima County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is February 20 and the first fall frost November 27.

Where ZIP 85750 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 20
First frostNov 27
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 Tucson, 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 Tucson, AZ

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostFebruary 20median — 50% chance of a later frost
Safe for tender plantsMarch 11only 10% chance of frost after
First fall frostNovember 27median — 10% chance by Nov 10
Growing season280 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 30 and returns around December 10.

From the NOAA station Tucson Camp Ave Exp, AZ — 6 miles away, elevation 2,330 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 85750

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Jan 9 – Jan 23
SpinachSow outdoors · Jan 9 – Jan 30
Broccoli, cabbageStart indoors · Dec 12 – Dec 26
Broccoli, cabbageTransplant · Jan 30 – Feb 13
Onion setsPlant outdoors · Jan 23 – Feb 6
PotatoesPlant outdoors · Jan 30 – Feb 13
LettuceSow outdoors · Jan 23 – Feb 6
Carrots, beetsSow outdoors · Jan 30 – Feb 13
TomatoesStart indoors · Dec 26 – Jan 9
TomatoesTransplant · Feb 27 – Mar 13
Peppers, eggplantStart indoors · Dec 12 – Dec 26
Peppers, eggplantTransplant · Mar 6 – Mar 20
BeansSow outdoors · Feb 27 – Mar 13
Sweet cornSow outdoors · Feb 27 – Mar 13
Cucumbers, squashSow outdoors · Feb 27 – Mar 13
Fall lettuce, spinachSow outdoors · Oct 2 – Oct 16
GarlicPlant cloves · Nov 13 – Dec 18
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 20) and first fall frost (Nov 27) 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 85750 came on Jan 22 — 4 days earlier than the 1991–2020 average (Jan 26).

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 Tucson, AZ.

Soil in Tucson, AZ

The soil mapped at the center of ZIP 85750 is Pinaleno — very cobbly sandy loam, well drained.

TextureVery cobbly sandy loamdrains and warms fast; dries out and needs more feeding
pH7.2neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Pinaleno-Stagecoach-Palos Verdes complex, 10 to 35 percent slopes.

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 85750; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Tucson, AZ

Summer high102 °Faverage high, June
Winter low36 °Faverage low, December
Hot days166days a year at 90 °F or more
Freezing nights26nights a year at 32 °F or less
Growing degree days7,312base 50 °F — the season’s usable heat
Longest day14 h 16 mindaylight on June 21
Shortest day10 h 02 mindaylight on December 21
Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb
Precipitation12.4 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°100°110°32 °FJanuary: average high 68 °F, low 37 °F 68°37° JanFebruary: average high 71 °F, low 40 °F 71°40° FebMarch: average high 78 °F, low 45 °F 78°45° MarApril: average high 85 °F, low 50 °F 85°50° AprMay: average high 93 °F, low 58 °F 93°58° MayJune: average high 102 °F, low 68 °F 102°68° JunJuly: average high 101 °F, low 75 °F 101°75° JulAugust: average high 100 °F, low 74 °F 100°74° AugSeptember: average high 96 °F, low 68 °F 96°68° SepOctober: average high 88 °F, low 55 °F 88°55° OctNovember: average high 77 °F, low 43 °F 77°43° NovDecember: average high 67 °F, low 36 °F 67°36° Dec

Precipitation by month inches

0″1″2″3″January: 1.24 in precipitation 1.2 JanFebruary: 1.10 in precipitation 1.1 FebMarch: 0.72 in precipitation 0.7 MarApril: 0.28 in precipitation 0.3 AprMay: 0.18 in precipitation 0.2 MayJune: 0.34 in precipitation 0.3 JunJuly: 2.21 in precipitation 2.2 JulAugust: 2.43 in precipitation 2.4 AugSeptember: 1.33 in precipitation 1.3 SepOctober: 0.84 in precipitation 0.8 OctNovember: 0.64 in precipitation 0.6 NovDecember: 1.13 in precipitation 1.1 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Tucson Camp Ave Exp, AZ (6 mi away); precipitation: Tucson 8.5 Ne, AZ (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

6 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

857159b
Tucson, AZ · 4 mi
857129b
Tucson, AZ · 4 mi
857189a
Tucson, AZ · 5 mi
857109b
Tucson, AZ · 6 mi
857169b
Tucson, AZ · 6 mi
857119b
Tucson, AZ · 6 mi
857499a
Tucson, AZ · 7 mi
857199b
Tucson, AZ · 7 mi

All 53 ZIP codes in Tucson → · Arizona planting zones →

Questions about 85750

What planting zone is ZIP code 85750?

ZIP code 85750 (Tucson, 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 Tucson, AZ?

The median last spring frost (32 °F) near 85750 is February 20; after March 11 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Tucson Camp Ave Exp station.

When is the first frost in Tucson, AZ?

The median first fall frost near 85750 is November 27, giving a median frost-free growing season of 280 days.

When should I plant tomatoes in 85750?

Start tomato seeds indoors around Dec 26 – Jan 9 and set transplants outside around Feb 27 – Mar 13, one to three weeks after the median last frost.

How much rain and snow does 85750 get?

About 12.4 inches of precipitation a year (NOAA 1991–2020 normals, Tucson 8.5 Ne station).

How hot do summers get in Tucson, AZ?

The average high peaks at 102 °F in June, with about 166 days a year at 90 °F or more.

What kind of soil does 85750 have?

The USDA soil survey maps Pinaleno at the center of ZIP 85750: very cobbly sandy loam, well drained, pH about 7.2 (neutral).

Did spring come early in Tucson, AZ in 2026?

Spring leaf-out near 85750 came on Jan 22 in 2026, 4 days earlier than the 1991–2020 average (Jan 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Tucson, AZ?

Short-day onions: the longest day near 85750 is 14 h 16 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.