Grand Terrace, 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 Grand Terrace compares
- In a typical year, frost nights in Grand Terrace fall between January 2 and January 10. In 1 year in 10 the first frost comes as early as December 11, or the last frost as late as February 17.
- Compared with Colton, CA, 2 km away, the last frost here is 17 days earlier than there.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | December 20 |
| 50% (median) | January 10 |
| 10% (safe for tender plants) | February 17 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | December 11 |
| 50% (median) | January 2 |
| 90% (late) | February 7 |
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
Grand Terrace, 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 Citrus Exp, CA weather station, 8 km away (elevation 988 ft (301 m)).
Frost dates near Grand Terrace
- Colton Jan 27 · Dec 19
- Loma Linda Jan 27 · Dec 19
- Bryn Mawr Jan 27 · Dec 19
- Bloomington Jan 10 · Jan 2
- San Bernardino Jan 27 · Dec 19
- March Air Reserve Base Jan 9 · Dec 25
- Riverside Jan 9 · Dec 25
- Redlands Jan 27 · Dec 19
- Rialto Jan 10 · Jan 2
- Moreno Valley rare frost
Frequently asked questions
When is the last frost in Grand Terrace, CA?
The median last spring frost in Grand Terrace, CA is January 10. There is still about a 10% chance of frost after February 17, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Grand Terrace, CA?
The median first fall frost is January 2, with about a 10% chance of frost before December 11.
How long is the growing season in Grand Terrace, CA?
About 357 days between the median last spring frost and first fall frost.
What planting zone is Grand Terrace, CA?
Grand Terrace, CA is in USDA hardiness zone 10a.