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

Planting zone for Maricopa, AZ

Maricopa, AZ is in USDA zone 9a across its 2 ZIP codes. The median last spring frost is February 23 and the first fall frost November 24.

Maricopa on the zone map

Outlined: its 2 ZIP code areas · 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

ZIP codes2

Last frostFeb 23

First frostNov 24

Growing season274 days

9a 2 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Maricopa, 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 Maricopa, AZ

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostFebruary 23median — 50% chance of a later frost

Safe for tender plantsMarch 15only 10% chance of frost after

First fall frostNovember 24median — 10% chance by Nov 10

Growing season274 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 2 and returns around December 6.

From the NOAA station Maricopa 4 N, AZ, elevation 1,161 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 Maricopa

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Jan 12 – Jan 26

SpinachSow outdoors · Jan 12 – Feb 2

Broccoli, cabbageStart indoors · Dec 15 – Dec 29

Broccoli, cabbageTransplant · Feb 2 – Feb 16

Onion setsPlant outdoors · Jan 26 – Feb 9

PotatoesPlant outdoors · Feb 2 – Feb 16

LettuceSow outdoors · Jan 26 – Feb 9

Carrots, beetsSow outdoors · Feb 2 – Feb 16

TomatoesStart indoors · Dec 29 – Jan 12

TomatoesTransplant · Mar 2 – Mar 16

Peppers, eggplantStart indoors · Dec 15 – Dec 29

Peppers, eggplantTransplant · Mar 9 – Mar 23

BeansSow outdoors · Mar 2 – Mar 16

Sweet cornSow outdoors · Mar 2 – Mar 16

Cucumbers, squashSow outdoors · Mar 2 – Mar 16

Fall lettuce, spinachSow outdoors · Sep 29 – Oct 13

GarlicPlant cloves · Nov 10 – Dec 15

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 23) and first fall frost (Nov 24) 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 85138 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 Maricopa, AZ.

Soil in Maricopa, AZ

The soil mapped at the center of ZIP 85138 is Glenbar — clay loam, well drained.

TextureClay loamholds water and nutrients; slow to drain and warm up

pH7.8slightly alkaline; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter0.5%low — add compost

Hydrologic groupCwater soaks in slowly

Farmland classPrime farmland if irrigated and either protected from flooding or not frequently flooded during the growing seasonUSDA classification

Map unit: Glenbar clay 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 85138; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Maricopa, AZ

Summer high109 °Faverage high, July

Winter low35 °Faverage low, December

Hot days183days a year at 90 °F or more

Freezing nights32nights a year at 32 °F or less

Growing degree days8,135base 50 °F — the season’s usable heat

Longest day14 h 20 mindaylight on June 21

Shortest day9 h 58 mindaylight on December 21

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

Precipitation7.1 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: Maricopa 4 N, AZ (7 mi away); precipitation: Maricopa 4 N, AZ (7 mi away). Daylight is calculated from latitude.

ZIP codes in Maricopa

Arizona planting zones →

Questions about Maricopa

What planting zone is Maricopa, AZ?

Maricopa, AZ is in USDA hardiness zone 9a on the 2023 map (9a: 20 to 25 °F).

When is the last frost in Maricopa, AZ?

The median last spring frost is February 23 and the median first fall frost is November 24 (NOAA 1991–2020 normals, Maricopa 4 N station).

When can I plant a garden in Maricopa, AZ?

Cool-season crops like peas and spinach go in around Jan 12 – Feb 2; tomatoes, peppers, beans and squash after about Mar 2, once frost risk has passed.

What kind of onions grow in Maricopa, AZ?

Intermediate onions: the longest day is 14 h 20 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

How much rain and snow does Maricopa, AZ get?

About 7.1 inches of precipitation a year (NOAA 1991–2020 normals).