March Air Reserve Base, CA frost dates
Frost is light and occasional here — typically a few cold nights around midwinter (about 2 a year). Cover tender plants when frost is forecast.
How March Air Reserve Base compares
- In a typical year, frost nights in March Air Reserve Base fall between December 25 and January 9. In 1 year in 10 the first frost comes as early as December 1, or the last frost as late as February 25.
- March Air Reserve Base shares its weather station with Riverside, CA, 0 km away, so the two have the same frost dates.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | December 16 |
| 50% (median) | January 9 |
| 10% (safe for tender plants) | February 25 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | December 1 |
| 50% (median) | December 25 |
| 90% (late) | January 27 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Gardening where frost is rare
March Air Reserve Base, CA only freezes on a few winter nights, so the usual "plant after the last frost" rule doesn't apply. Heat and rainfall decide the seasons instead:
- Cool-season crops (lettuce, broccoli, peas, carrots) grow best from fall through late winter.
- Warm-season crops (tomatoes, peppers, beans, squash) do best planted in late winter to spring, and again in late summer for a fall crop — midsummer heat can stop tomatoes setting fruit.
- Heat lovers (okra, sweet potatoes, melons) can be planted through spring and early summer.
About these dates
Based on 1991–2020 NOAA climate normals for the Riverside Fire Stn, CA weather station, about 1 km away (elevation 840 ft (256 m)).
Frost dates near March Air Reserve Base
- Riverside Jan 9 · Dec 25
- Grand Terrace Jan 10 · Jan 2
- Bloomington Jan 10 · Jan 2
- Mira Loma Jan 9 · Dec 30
- Colton Jan 27 · Dec 19
- Norco Jan 17 · Dec 19
- Fontana Jan 4 · Dec 30
- Moreno Valley rare frost
- Loma Linda Jan 27 · Dec 19
- Corona Jan 9 · Dec 30
Frequently asked questions
When is the last frost in March Air Reserve Base, CA?
The median last spring frost in March Air Reserve Base, CA is January 9. There is still about a 10% chance of frost after February 25, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in March Air Reserve Base, CA?
The median first fall frost is December 25, with about a 10% chance of frost before December 1.
How long is the growing season in March Air Reserve Base, CA?
About 350 days between the median last spring frost and first fall frost.
What planting zone is March Air Reserve Base, CA?
March Air Reserve Base, CA is in USDA hardiness zone 9b.