Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 85634 — Sells, AZ

ZIP code 85634 (Sells, Pima County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is April 26 and the first fall frost November 4.

Where ZIP 85634 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 frostApr 26

First frostNov 4

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 Sells, 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 Sells, AZ

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostApril 26median — 50% chance of a later frost

Safe for tender plantsMay 17only 10% chance of frost after

First fall frostNovember 4median — 10% chance by Oct 18

Growing season195 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 7 and returns around November 17.

From the NOAA station Kitt Peak, AZ — 25 miles away, elevation 6,792 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 85634

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 15 – Mar 29

SpinachSow outdoors · Mar 15 – Apr 5

Broccoli, cabbageStart indoors · Feb 15 – Mar 1

Broccoli, cabbageTransplant · Apr 5 – Apr 19

Onion setsPlant outdoors · Mar 29 – Apr 12

PotatoesPlant outdoors · Apr 5 – Apr 19

LettuceSow outdoors · Mar 29 – Apr 12

Carrots, beetsSow outdoors · Apr 5 – Apr 19

TomatoesStart indoors · Mar 1 – Mar 15

TomatoesTransplant · May 3 – May 17

Peppers, eggplantStart indoors · Feb 15 – Mar 1

Peppers, eggplantTransplant · May 10 – May 24

BeansSow outdoors · May 3 – May 17

Sweet cornSow outdoors · May 3 – May 17

Cucumbers, squashSow outdoors · May 3 – May 17

Fall lettuce, spinachSow outdoors · Sep 9 – Sep 23

GarlicPlant cloves · Oct 21 – Nov 25

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 26) and first fall frost (Nov 4) 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 85634 came on Jan 23 — 3 days earlier than the 1991–2020 average (Jan 26).

average
Jan 262026
Jan 23

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.

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 Sells, AZ.

Soil in Sells, AZ

The soil mapped at the center of ZIP 85634 is Bucklebar — sandy loam, well drained.

TextureSandy 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 groupBwater soaks in moderately

Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Bucklebar-Hayhook-Tubac complex, 0 to 3 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 85634; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Sells, AZ

Summer high80 °Faverage high, June

Winter low34 °Faverage low, January

Hot days4days a year at 90 °F or more

Freezing nights59nights a year at 32 °F or less

Growing degree days3,241base 50 °F — the season’s usable heat

Longest day14 h 15 mindaylight on June 21

Shortest day10 h 03 mindaylight on December 21

Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb

Precipitation19.9 inper year, rain and melted snow

Snowfall8 inper year; 4 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Kitt Peak, AZ (25 mi away); precipitation: Kitt Peak, AZ (25 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.

Lukeville, AZ · 41 mi

Arizona planting zones →

Questions about 85634

What planting zone is ZIP code 85634?

ZIP code 85634 (Sells, 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 Sells, AZ?

The median last spring frost (32 °F) near 85634 is April 26; after May 17 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Kitt Peak station.

When is the first frost in Sells, AZ?

The median first fall frost near 85634 is November 4, giving a median frost-free growing season of 195 days.

When should I plant tomatoes in 85634?

Start tomato seeds indoors around Mar 1 – Mar 15 and set transplants outside around May 3 – May 17, one to three weeks after the median last frost.

How much rain and snow does 85634 get?

About 19.9 inches of precipitation a year and 8 inches of snowfall (NOAA 1991–2020 normals, Kitt Peak station).

How hot do summers get in Sells, AZ?

The average high peaks at 80 °F in June, with about 4 days a year at 90 °F or more.

What kind of soil does 85634 have?

The USDA soil survey maps Bucklebar at the center of ZIP 85634: sandy loam, well drained, pH about 7.2 (neutral).

Did spring come early in Sells, AZ in 2026?

Spring leaf-out near 85634 came on Jan 23 in 2026, 3 days earlier than the 1991–2020 average (Jan 26), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Sells, AZ?

Short-day onions: the longest day near 85634 is 14 h 15 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.