When to plant in Tempe, AZ
USDA Zone 10aEverything below — frost dates, hardiness zone, and what to plant when in Tempe, Arizona — is derived from the closest NOAA station with complete climate normals.
A generous ~295-day season lets Tempe gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. In zone 10a, frost is a minor factor for Tempe — most perennials thrive, and annual vegetables can go out early and stay late.
The average last spring frost in Tempe is now 9 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
TEMPE ASU · 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 Tempe’s own odds, recorded at TEMPE ASU.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Apr 7 | Mar 8 | Feb 14 | Nov 7 | Nov 26 | Dec 9 |
| 32°F | Mar 9 | Feb 13 | Jan 12 | Nov 18 | Dec 5 | Dec 24 |
| 28°F | Feb 19 | Jan 16 | Dec 19 | Nov 27 | Dec 19 | Jan 19 |
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 Tempe, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 13 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.
Tempe planting FAQ
When is the last spring frost in Tempe, AZ?
Plan for the last spring frost in Tempe around February 13 (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 Tempe, AZ?
The first fall frost in Tempe typically arrives around December 5 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Tempe in?
Tempe is in USDA hardiness zone 10a. In zone 10a, winters are mild — many tender perennials overwinter here.
How long is the growing season in Tempe?
Tempe has about 295 frost-free days — a long growing season — between the average last spring frost (February 13) and first fall frost (December 5).
When should I plant tomatoes in Tempe?
For Tempe, sow tomatoes indoors about December 19–January 2 and move the seedlings out around February 20, after the last spring frost.
Never miss a window in Tempe
An email when it’s time to start seeds, transplant, and sow — timed to Tempe’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Chandler · 14 km
- Paradise Valley · 18 km
- Gilbert · 20 km
- Mesa · 20 km
- Sun Lakes · 20 km
- Phoenix · 25 km
- Glendale · 29 km
- Fountain Hills · 30 km
Frost dates recorded at TEMPE ASU, 4 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 Tempe, AZ — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00028499. Retrieved from https://blissgarden.com/arizona/tempe.