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

Planting zone for 85632 — San Simon, AZ

ZIP code 85632 (San Simon, Cochise County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is April 21 and the first fall frost October 27.

Where ZIP 85632 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.

Zone8a10 to 15 °F
Coldest night−12.2 to −9.4 °C
Last frostApr 21
First frostOct 27
2012 zone8a

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 8a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for San Simon, 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 San Simon, AZ

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 21median — 50% chance of a later frost
Safe for tender plantsMay 8only 10% chance of frost after
First fall frostOctober 27median — 10% chance by Oct 16
Growing season188 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 3 and returns around November 5.

From the NOAA station Paradise, AZ — 9 miles away, elevation 5,460 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 85632

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 10 – Mar 24
SpinachSow outdoors · Mar 10 – Mar 31
Broccoli, cabbageStart indoors · Feb 10 – Feb 24
Broccoli, cabbageTransplant · Mar 31 – Apr 14
Onion setsPlant outdoors · Mar 24 – Apr 7
PotatoesPlant outdoors · Mar 31 – Apr 14
LettuceSow outdoors · Mar 24 – Apr 7
Carrots, beetsSow outdoors · Mar 31 – Apr 14
TomatoesStart indoors · Feb 24 – Mar 10
TomatoesTransplant · Apr 28 – May 12
Peppers, eggplantStart indoors · Feb 10 – Feb 24
Peppers, eggplantTransplant · May 5 – May 19
BeansSow outdoors · Apr 28 – May 12
Sweet cornSow outdoors · Apr 28 – May 12
Cucumbers, squashSow outdoors · Apr 28 – May 12
Fall lettuce, spinachSow outdoors · Sep 1 – Sep 15
GarlicPlant cloves · Oct 13 – Nov 17
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 21) and first fall frost (Oct 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 85632 came on Feb 1 — 4 days earlier than the 1991–2020 average (Feb 5).

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).

Soil in San Simon, AZ

The soil mapped at the center of ZIP 85632 is Santo Tomas — cobbly fine sandy loam, well drained.

TextureCobbly fine 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 matter2.5%moderate
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Santo Tomas soils.

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 85632; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in San Simon, AZ

Summer high90 °Faverage high, June
Winter low24 °Faverage low, January
Hot days46days a year at 90 °F or more
Freezing nights116nights a year at 32 °F or less
Growing degree days3,575base 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
Precipitation17 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 54 °F, low 24 °F 54°24° JanFebruary: average high 59 °F, low 28 °F 59°28° FebMarch: average high 65 °F, low 33 °F 65°33° MarApril: average high 73 °F, low 39 °F 73°39° AprMay: average high 81 °F, low 46 °F 81°46° MayJune: average high 90 °F, low 55 °F 90°55° JunJuly: average high 88 °F, low 61 °F 88°61° JulAugust: average high 84 °F, low 58 °F 84°58° AugSeptember: average high 80 °F, low 53 °F 80°53° SepOctober: average high 74 °F, low 42 °F 74°42° OctNovember: average high 63 °F, low 32 °F 63°32° NovDecember: average high 54 °F, low 26 °F 54°26° Dec

Precipitation by month inches

0″1″2″3″4″January: 1.14 in precipitation 1.1 JanFebruary: 1.28 in precipitation 1.3 FebMarch: 0.89 in precipitation 0.9 MarApril: 0.33 in precipitation 0.3 AprMay: 0.31 in precipitation 0.3 MayJune: 0.61 in precipitation 0.6 JunJuly: 3.58 in precipitation 3.6 JulAugust: 3.41 in precipitation 3.4 AugSeptember: 1.80 in precipitation 1.8 SepOctober: 1.01 in precipitation 1.0 OctNovember: 1.07 in precipitation 1.1 NovDecember: 1.53 in precipitation 1.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Paradise, AZ (9 mi away); precipitation: Paradise, AZ (9 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

880568a
Rodeo, NM · 18 mi
856058b
Bowie, AZ · 24 mi
880208a
Animas, NM · 28 mi
856258a
Pearce, AZ · 31 mi
880458a
Lordsburg, NM · 34 mi
856108b
Elfrida, AZ · 36 mi
880098a
Playas, NM · 39 mi
856178b
Mc Neal, AZ · 46 mi

Arizona planting zones →

Questions about 85632

What planting zone is ZIP code 85632?

ZIP code 85632 (San Simon, AZ) is in USDA hardiness zone 8a on the 2023 map: the coldest night of an average winter reaches 10 to 15 °F (−12.2 to −9.4 °C).

When is the last frost in San Simon, AZ?

The median last spring frost (32 °F) near 85632 is April 21; after May 8 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Paradise station.

When is the first frost in San Simon, AZ?

The median first fall frost near 85632 is October 27, giving a median frost-free growing season of 188 days.

When should I plant tomatoes in 85632?

Start tomato seeds indoors around Feb 24 – Mar 10 and set transplants outside around Apr 28 – May 12, one to three weeks after the median last frost.

How much rain and snow does 85632 get?

About 17 inches of precipitation a year (NOAA 1991–2020 normals, Paradise station).

How hot do summers get in San Simon, AZ?

The average high peaks at 90 °F in June, with about 46 days a year at 90 °F or more.

What kind of soil does 85632 have?

The USDA soil survey maps Santo Tomas at the center of ZIP 85632: cobbly fine sandy loam, well drained, pH about 7.2 (neutral).

Did spring come early in San Simon, AZ in 2026?

Spring leaf-out near 85632 came on Feb 1 in 2026, 4 days earlier than the 1991–2020 average (Feb 5), according to the USA National Phenology Network Spring Index.

What kind of onions grow in San Simon, AZ?

Short-day onions: the longest day near 85632 is 14 h 15 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.