Frost dates · USDA zone 10a
Frost dates for Tempe, AZ
Tempe, AZ sees its last 32 °F night of spring around February 13 and its first of fall around December 5 — a 298-day freeze-free season in a typical year.
Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.
Freeze odds, by date
| Odds | Last spring freeze after | First fall freeze before |
|---|---|---|
| 9 years in 10 | Jan 12 | Dec 24 |
| Median — 1 year in 2 | Feb 13 | Dec 5 |
| 1 year in 10 | Mar 9 | Nov 18 |
The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 298 days median, at least 266 in 9 years of 10, at least 331 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of Jan 16 and first of Dec 19.
Tempe planting calendar, 2027
Every row runs from the median last frost (Feb 13) and median first frost (Dec 5) above, using each cultivar's days to maturity. Same engine as the Plan Builder.
| Crop | Start indoors | Transplant / plant | First harvest | Days |
|---|---|---|---|---|
| Hardneck GarlicSiberian (porcelain hardneck) | — | Oct 15prior fall | Jun 12 | 240 from sow |
| Spanish OnionYellow Sweet Spanish (long-day) | Nov 21 | Jan 16 | May 6 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | Feb 13 | Mar 15 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Jan 30 | Jan 30 | Mar 16 | 45 from sow |
| Genovese BasilGenovese | Jan 16 | Feb 27 | Apr 28 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Dec 19 | Feb 20 | May 6 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Dec 5 | Feb 27 | Jun 2 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Dec 19 | Feb 20 | May 6 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Dec 19 | Feb 20 | May 11 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Dec 19 | Feb 20 | May 11 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Jan 30 | Jan 30 | Apr 10 | 70 from sow |
| TomatilloToma Verde | Jan 2 | Feb 20 | May 1 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Jan 2 | Feb 20 | May 6 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Jan 2 | Feb 20 | May 11 | 80 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.
What sauce can Tempe grow?
Each sauce, scheduled for a Tempe container garden: when the first seeds go in and when enough fruit has ripened for one batch.
Tempe frost questions
When is the last frost in Tempe, AZ?
The median last 32 °F freeze at TEMPE ASU, AZ is February 13: half of years see a later one. One year in ten, a freeze still comes after March 9; nine years in ten, it comes after January 12. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in Tempe, AZ?
The median first 32 °F freeze of fall is December 5. One year in ten it arrives before November 18; nine years in ten, before December 24.
How long is the growing season in Tempe, AZ?
298 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 266 days; one year in ten, at least 331 days.
What growing zone is Tempe, AZ?
USDA hardiness zone 10a, per the 2023 USDA Plant Hardiness Zone Map for ZIP 85282. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.
When should I plant tomatoes in Tempe, AZ?
Start Roma VF (determinate paste) seeds indoors around Jan 2 and transplant around Feb 20, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Mar 9. First ripe fruit lands around May 6.
When should I plant peppers in Tempe, AZ?
Sow jalapeño indoors on a heat mat around Dec 19; transplant no earlier than Feb 20, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around May 6.
Nearby in Arizona
- Chandlerlast frost Feb 1
- Gilbertlast frost Feb 1
- Mesalast frost Feb 1
- Phoenixlast frost Jan 8
- Glendalelast frost Jan 20
- Scottsdalelast frost Jan 27
All Arizona frost dates → · How frost-date math drives a sowing calendar →