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When to plant in Maricopa, AZ

USDA Zone 9a

Maricopa, Arizona frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.

A generous ~274-day season lets Maricopa gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. Zone 9a is warm enough that Maricopa can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · MARICOPA 4 N · 8.5 km
Last spring frost
February 23
50% chance · 32°F
First fall frost
November 24
50% chance · 32°F
Growing season
274 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for MaricopaA year-band showing 32°F frost risk from January to December for Maricopa: last spring frost around February 23, first fall frost around November 24, about 274 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average last spring frost in Maricopa is now 7 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

MARICOPA 4 N · 1991–2020

The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Maricopa’s own odds, recorded at MARICOPA 4 N.

Frost-probability curves for MaricopaProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 23 and the first fall frost around November 24, giving about 274 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FApr 10Mar 12Feb 24Oct 27Nov 14Nov 28
32°FMar 15Feb 23Jan 29Nov 10Nov 24Dec 8
28°FFeb 28Feb 2Dec 31Nov 21Dec 6Dec 23

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19
Fall sowin 16 days
Brussels Sprouts
August 4August 18

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in Maricopa, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 35 km · complete 32°F normals

When stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.

MARICOPA 4 N
Primary
9 km · 354 m elevation
SPRING
Feb 23
FALL
Nov 24
CASA GRANDE
32 km · 427 m elevation
SPRING
Feb 5
FALL
Dec 6
CHANDLER HEIGHTS
35 km · 434 m elevation
SPRING
Feb 1
FALL
Dec 11

Maricopa planting FAQ

When is the last spring frost in Maricopa, AZ?

Plan for the last spring frost in Maricopa around February 23 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.

When is the first fall frost in Maricopa, AZ?

Expect Maricopa's first fall frost near November 24 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Maricopa in?

Maricopa is in USDA hardiness zone 9a. In zone 9a, winters are mild — many tender perennials overwinter here.

How long is the growing season in Maricopa?

There are roughly 274 frost-free days in Maricopa (a long growing season), running from the average last frost around February 23 to the first fall frost near November 24.

When should I plant tomatoes in Maricopa?

In Maricopa, start tomato seeds indoors around December 29–January 12, then transplant seedlings outdoors around March 2 once the danger of frost has passed.

Planting reminders

Never miss a window in Maricopa

An email when it’s time to start seeds, transplant, and sow — timed to Maricopa’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at MARICOPA 4 N, 9 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in Maricopa, AZ — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00025270. Retrieved from https://blissgarden.com/arizona/maricopa.
When to Plant in Maricopa, AZ — Frost Dates & Zone 9a — BlissGarden