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When to plant in Scottsdale, AZ

USDA Zone 10a

Here are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Scottsdale, Arizona — all computed from Scottsdale's nearest NOAA weather station.

With about 328 frost-free days, Scottsdale supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Zone 10a is warm enough that Scottsdale can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · PINNACLE PEAK · 4.8 km
Last spring frost
January 27
50% chance · 32°F
First fall frost
December 21
50% chance · 32°F
Growing season
328 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for ScottsdaleA year-band showing 32°F frost risk from January to December for Scottsdale: last spring frost around January 27, first fall frost around December 21, about 328 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

PINNACLE PEAK · 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 Scottsdale’s own odds, recorded at PINNACLE PEAK.

Frost-probability curves for ScottsdaleProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 27 and the first fall frost around December 21, giving about 328 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°FMar 30Feb 26Jan 17Nov 19Dec 7Dec 24
32°FMar 5Jan 27Dec 23Nov 28Dec 21Jan 24
28°FFeb 8Jan 6Dec 14Dec 6Jan 1Feb 2

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

What to plant now

TODAY · JULY 19

Nothing new to sow or transplant outdoors in the next few weeks — a seasonal lull. Check the full-year calendar below for the next window.

Add the next planting windows to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

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

Nearby weather stations

3 within 15 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.

PINNACLE PEAK
Primary
5 km · 782 m elevation
SPRING
Jan 27
FALL
Dec 21
SCOTTSDALE MUNI AP
8 km · 449 m elevation
SPRING
Jan 6
FALL
Dec 26
CAREFREE
15 km · 771 m elevation
SPRING
Feb 4
FALL
Dec 16

Scottsdale planting FAQ

When is the last spring frost in Scottsdale, AZ?

Plan for the last spring frost in Scottsdale around January 27 (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 Scottsdale, AZ?

In Scottsdale, the first 32°F freeze of fall lands around December 21 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Scottsdale in?

Scottsdale is in USDA hardiness zone 10a. In zone 10a, winters are mild — many tender perennials overwinter here.

How long is the growing season in Scottsdale?

There are roughly 328 frost-free days in Scottsdale (a long growing season), running from the average last frost around January 27 to the first fall frost near December 21.

When should I plant tomatoes in Scottsdale?

In Scottsdale, start tomato seeds indoors around December 2–December 16, then transplant seedlings outdoors around February 3 once the danger of frost has passed.

Planting reminders

Never miss a window in Scottsdale

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

Nearby cities

8 within reach

Frost dates recorded at PINNACLE PEAK, 5 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 Scottsdale, AZ — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00026603. Retrieved from https://blissgarden.com/arizona/scottsdale.
When to Plant in Scottsdale, AZ — Frost Dates & Zone 10a — BlissGarden