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

Planting zone for 85263 — Rio Verde, AZ

ZIP code 85263 (Rio Verde, Maricopa County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F. The median last spring frost is March 7 and the first fall frost November 20.

Where ZIP 85263 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.

Zone9b25 to 30 °F

Coldest night−3.9 to −1.1 °C

Last frostMar 7

First frostNov 20

2012 zone9b

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 9b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Rio Verde, 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 Rio Verde, AZ

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMarch 7median — 50% chance of a later frost

Safe for tender plantsMarch 27only 10% chance of frost after

First fall frostNovember 20median — 10% chance by Nov 3

Growing season255 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 15 and returns around December 1.

From the NOAA station Punkin Center, AZ — 16 miles away, elevation 2,326 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 85263

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Jan 24 – Feb 7

SpinachSow outdoors · Jan 24 – Feb 14

Broccoli, cabbageStart indoors · Dec 27 – Jan 10

Broccoli, cabbageTransplant · Feb 14 – Feb 28

Onion setsPlant outdoors · Feb 7 – Feb 21

PotatoesPlant outdoors · Feb 14 – Feb 28

LettuceSow outdoors · Feb 7 – Feb 21

Carrots, beetsSow outdoors · Feb 14 – Feb 28

TomatoesStart indoors · Jan 10 – Jan 24

TomatoesTransplant · Mar 14 – Mar 28

Peppers, eggplantStart indoors · Dec 27 – Jan 10

Peppers, eggplantTransplant · Mar 21 – Apr 4

BeansSow outdoors · Mar 14 – Mar 28

Sweet cornSow outdoors · Mar 14 – Mar 28

Cucumbers, squashSow outdoors · Mar 14 – Mar 28

Fall lettuce, spinachSow outdoors · Sep 25 – Oct 9

GarlicPlant cloves · Nov 6 – Dec 11

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 7) and first fall frost (Nov 20) 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 85263 came on Feb 2 — about the same time as the 1991–2020 average (Feb 3).

average
Feb 32026
Feb 2

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 9b in Arizona

499 plants native to the lower 48 states, recorded in Arizona, and rated by the USDA to survive 25 °F or colder — the bottom of zone 9b. 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 Rio Verde, AZ.

Soil in Rio Verde, AZ

The soil mapped at the center of ZIP 85263 is Ustic Haplargids — extremely gravelly sandy loam, well drained.

TextureExtremely gravelly sandy loamdrains and warms fast; dries out and needs more feeding

pH5.8moderately acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.5%low — add compost

Hydrologic groupCwater soaks in slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Ustic Haplargids and Typic Torriorthents; cool thermic aridic fan piedmonts.

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 85263; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Rio Verde, AZ

Summer high103 °Faverage high, July

Winter low32 °Faverage low, January

Hot days145days a year at 90 °F or more

Freezing nights52nights a year at 32 °F or less

Growing degree days6,341base 50 °F — the season’s usable heat

Longest day14 h 25 mindaylight on June 21

Shortest day9 h 53 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation12.7 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Punkin Center, AZ (16 mi away); precipitation: Horseshoe Dam, 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.

852629b

Scottsdale, AZ · 15 mi

852649b

Fort Mcdowell, AZ · 17 mi

853779b

Carefree, AZ · 22 mi

853319b

Cave Creek, AZ · 22 mi

855418b

Payson, AZ · 23 mi

853279b

Cave Creek, AZ · 23 mi

8525510a

Scottsdale, AZ · 24 mi

8526610a

Scottsdale, AZ · 24 mi

Arizona planting zones →

Questions about 85263

What planting zone is ZIP code 85263?

ZIP code 85263 (Rio Verde, AZ) is in USDA hardiness zone 9b on the 2023 map: the coldest night of an average winter reaches 25 to 30 °F (−3.9 to −1.1 °C).

When is the last frost in Rio Verde, AZ?

The median last spring frost (32 °F) near 85263 is March 7; after March 27 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Punkin Center station.

When is the first frost in Rio Verde, AZ?

The median first fall frost near 85263 is November 20, giving a median frost-free growing season of 255 days.

When should I plant tomatoes in 85263?

Start tomato seeds indoors around Jan 10 – Jan 24 and set transplants outside around Mar 14 – Mar 28, one to three weeks after the median last frost.

How much rain and snow does 85263 get?

About 12.7 inches of precipitation a year (NOAA 1991–2020 normals, Horseshoe Dam station).

How hot do summers get in Rio Verde, AZ?

The average high peaks at 103 °F in July, with about 145 days a year at 90 °F or more.

What kind of soil does 85263 have?

The USDA soil survey maps Ustic Haplargids at the center of ZIP 85263: extremely gravelly sandy loam, well drained, pH about 5.8 (moderately acidic).

Did spring come early in Rio Verde, AZ in 2026?

Spring leaf-out near 85263 came on Feb 2 in 2026, about the same as the 1991–2020 average (Feb 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Rio Verde, AZ?

Intermediate onions: the longest day near 85263 is 14 h 25 min, so day-neutral types bulb best; long-day varieties may not bulb fully.