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

Planting zone for 85757 — Tucson, AZ

ZIP code 85757 (Tucson, Pima County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is February 8 and the first fall frost December 10.

Where ZIP 85757 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 8
First frostDec 10
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 8median — 50% chance of a later frost
Safe for tender plantsMarch 8only 10% chance of frost after
First fall frostDecember 10median — 10% chance by Nov 22
Growing season303 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 20 and returns around December 27.

From the NOAA station Tucson 11 W, AZ — 8 miles away, elevation 2,733 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 85757

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Dec 28 – Jan 11
SpinachSow outdoors · Dec 28 – Jan 18
Broccoli, cabbageStart indoors · Nov 30 – Dec 14
Broccoli, cabbageTransplant · Jan 18 – Feb 1
Onion setsPlant outdoors · Jan 11 – Jan 25
PotatoesPlant outdoors · Jan 18 – Feb 1
LettuceSow outdoors · Jan 11 – Jan 25
Carrots, beetsSow outdoors · Jan 18 – Feb 1
TomatoesStart indoors · Dec 14 – Dec 28
TomatoesTransplant · Feb 15 – Mar 1
Peppers, eggplantStart indoors · Nov 30 – Dec 14
Peppers, eggplantTransplant · Feb 22 – Mar 8
BeansSow outdoors · Feb 15 – Mar 1
Sweet cornSow outdoors · Feb 15 – Mar 1
Cucumbers, squashSow outdoors · Feb 15 – Mar 1
Fall lettuce, spinachSow outdoors · Oct 15 – Oct 29
GarlicPlant cloves · Nov 26 – Dec 31
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 8) and first fall frost (Dec 10) 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 85757 came on Jan 23 — about the same time as the 1991–2020 average (Jan 25).

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 85757 is Tubac — sandy loam, well drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding
pH6.5neutral; 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: Tubac sandy loam, 0 to 2 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 85757; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Tucson, AZ

Summer high100 °Faverage high, June
Winter low40 °Faverage low, December
Hot days149days a year at 90 °F or more
Freezing nights11nights a year at 32 °F or less
Growing degree days7,376base 50 °F — the season’s usable heat
Longest day14 h 15 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
Precipitation11.7 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 66 °F, low 41 °F 66°41° JanFebruary: average high 68 °F, low 42 °F 68°42° FebMarch: average high 75 °F, low 47 °F 75°47° MarApril: average high 82 °F, low 52 °F 82°52° AprMay: average high 91 °F, low 60 °F 91°60° MayJune: average high 100 °F, low 70 °F 100°70° JunJuly: average high 99 °F, low 75 °F 99°75° JulAugust: average high 98 °F, low 73 °F 98°73° AugSeptember: average high 94 °F, low 69 °F 94°69° SepOctober: average high 86 °F, low 58 °F 86°58° OctNovember: average high 74 °F, low 48 °F 74°48° NovDecember: average high 65 °F, low 40 °F 65°40° Dec

Precipitation by month inches

0″1″2″3″January: 0.99 in precipitation 1.0 JanFebruary: 0.76 in precipitation 0.8 FebMarch: 0.72 in precipitation 0.7 MarApril: 0.30 in precipitation 0.3 AprMay: 0.29 in precipitation 0.3 MayJune: 0.35 in precipitation 0.3 JunJuly: 2.14 in precipitation 2.1 JulAugust: 2.14 in precipitation 2.1 AugSeptember: 1.31 in precipitation 1.3 SepOctober: 1.11 in precipitation 1.1 OctNovember: 0.60 in precipitation 0.6 NovDecember: 1.00 in precipitation 1.0 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Tucson 11 W, AZ (8 mi away); precipitation: Valencia West 1.1 E, AZ (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

857469a
Tucson, AZ · 4 mi
857139b
Tucson, AZ · 8 mi
857099b
Tucson, AZ · 8 mi
857459b
Tucson, AZ · 9 mi
857239b
Tucson, AZ · 10 mi
857149b
Tucson, AZ · 11 mi
857019b
Tucson, AZ · 11 mi
857069b
Tucson, AZ · 11 mi

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

Questions about 85757

What planting zone is ZIP code 85757?

ZIP code 85757 (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 85757 is February 8; after March 8 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Tucson 11 W station.

When is the first frost in Tucson, AZ?

The median first fall frost near 85757 is December 10, giving a median frost-free growing season of 303 days.

When should I plant tomatoes in 85757?

Start tomato seeds indoors around Dec 14 – Dec 28 and set transplants outside around Feb 15 – Mar 1, one to three weeks after the median last frost.

How much rain and snow does 85757 get?

About 11.7 inches of precipitation a year (NOAA 1991–2020 normals, Valencia West 1.1 E station).

How hot do summers get in Tucson, AZ?

The average high peaks at 100 °F in June, with about 149 days a year at 90 °F or more.

What kind of soil does 85757 have?

The USDA soil survey maps Tubac at the center of ZIP 85757: sandy loam, well drained, pH about 6.5 (neutral).

Did spring come early in Tucson, AZ in 2026?

Spring leaf-out near 85757 came on Jan 23 in 2026, about the same as the 1991–2020 average (Jan 25), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Tucson, AZ?

Short-day onions: the longest day near 85757 is 14 h 15 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.