Frost dates · USDA zone 9b
Frost dates for San Jacinto, CA
San Jacinto, CA sees its last 32 °F night of spring around January 31 and its first of fall around December 10 — a 315-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 | Dec 31 (prior winter) | Jan 6 (next year) |
| Median — 1 year in 2 | Jan 31 | Dec 10 |
| 1 year in 10 | Feb 28 | Nov 22 |
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: 315 days median, at least 274 in 9 years of 10, at least 348 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 3 and first of Dec 21.
San Jacinto planting calendar, 2027
Every row runs from the median last frost (Jan 31) and median first frost (Dec 10) 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 8 | Jan 3 | Apr 23 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | Jan 31 | Mar 2 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Jan 17 | Jan 17 | Mar 3 | 45 from sow |
| Genovese BasilGenovese | Jan 3 | Feb 14 | Apr 15 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Dec 6 | Feb 7 | Apr 23 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Nov 22 | Feb 14 | May 20 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Dec 6 | Feb 7 | Apr 23 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Dec 6 | Feb 7 | Apr 28 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Dec 6 | Feb 7 | Apr 28 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Jan 17 | Jan 17 | Mar 28 | 70 from sow |
| TomatilloToma Verde | Dec 20 | Feb 7 | Apr 18 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Dec 20 | Feb 7 | Apr 23 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Dec 20 | Feb 7 | Apr 28 | 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 San Jacinto grow?
Each sauce, scheduled for a San Jacinto container garden: when the first seeds go in and when enough fruit has ripened for one batch.
San Jacinto frost questions
When is the last frost in San Jacinto, CA?
The median last 32 °F freeze at SAN JACINTO, CA is January 31: half of years see a later one. One year in ten, a freeze still comes after February 28; nine years in ten, it comes after December 31 (prior winter). Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in San Jacinto, CA?
The median first 32 °F freeze of fall is December 10. One year in ten it arrives before November 22; nine years in ten, before January 6 (next year).
How long is the growing season in San Jacinto, CA?
315 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 274 days; one year in ten, at least 348 days.
What growing zone is San Jacinto, CA?
USDA hardiness zone 9b, per the 2023 USDA Plant Hardiness Zone Map for ZIP 92582. 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 San Jacinto, CA?
Start Roma VF (determinate paste) seeds indoors around Dec 20 and transplant around Feb 7, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Feb 28. First ripe fruit lands around Apr 23.
When should I plant peppers in San Jacinto, CA?
Sow jalapeño indoors on a heat mat around Dec 6; transplant no earlier than Feb 7, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Apr 23.
Nearby in California
- Hemetlast frost Jan 31
- Beaumontlast frost Jan 31
- Perrislast frost Jan 10
- Menifeelast frost Jan 28
- Moreno Valleylast frost Jan 10
- Yucaipalast frost Jan 27
All California frost dates → · How frost-date math drives a sowing calendar →