When to plant in Coolidge, AZ
USDA Zone 9aCoolidge, Arizona frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
With about 285 frost-free days, Coolidge supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Zone 9a is warm enough that Coolidge can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.
The average last spring frost in Coolidge is now 10 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
CASA GRANDE NM · 1991–2020The 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 Coolidge’s own odds, recorded at CASA GRANDE NM.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Apr 5 | Mar 8 | Feb 16 | Nov 4 | Nov 19 | Dec 3 |
| 32°F | Mar 8 | Feb 17 | Jan 22 | Nov 12 | Nov 29 | Dec 15 |
| 28°F | Feb 23 | Jan 26 | Dec 26 | Nov 23 | Dec 12 | Jan 6 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Coolidge, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 17 km · complete 32°F normalsWhen 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.
Coolidge planting FAQ
When is the last spring frost in Coolidge, AZ?
Coolidge's average last spring frost falls near February 17 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Coolidge, AZ?
In Coolidge, the first 32°F freeze of fall lands around November 29 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Coolidge in?
Coolidge is in USDA hardiness zone 9a. In zone 9a, winters are mild — many tender perennials overwinter here.
How long is the growing season in Coolidge?
There are roughly 285 frost-free days in Coolidge (a long growing season), running from the average last frost around February 17 to the first fall frost near November 29.
When should I plant tomatoes in Coolidge?
In Coolidge, start tomato seeds indoors around December 23–January 6, then transplant seedlings outdoors around February 24 once the danger of frost has passed.
Never miss a window in Coolidge
An email when it’s time to start seeds, transplant, and sow — timed to Coolidge’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Florence · 18 km
- Eloy · 22 km
- Casa Grande · 23 km
- San Tan Valley · 27 km
- Queen Creek · 35 km
- Sun Lakes · 45 km
- Maricopa · 46 km
- Gilbert · 47 km
Frost dates recorded at CASA GRANDE NM, 7 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Coolidge, AZ — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00021314. Retrieved from https://blissgarden.com/arizona/coolidge.