Frost dates for 94596 — Walnut Creek, CA
Frost is light and occasional here — typically a few cold nights around midwinter (about 4 a year). Cover tender plants when frost is forecast.
How Walnut Creek compares
- In a typical year, frost nights in Walnut Creek fall between December 19 and January 7. In 1 year in 10 the first frost comes as early as December 1, or the last frost as late as February 1.
- Compared with Concord, CA, 8 km away, the last frost here is 2 days earlier than there.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | December 19 |
| 50% (median) | January 7 |
| 10% (safe for tender plants) | February 1 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | December 1 |
| 50% (median) | December 19 |
| 90% (late) | January 12 |
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
Walnut Creek, 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 Concord Wwtp, CA weather station, 9 km away (elevation 39 ft (12 m)).
ZIP codes in Walnut Creek: 94595 94596 94597 94598
Frost dates near Walnut Creek
- Lafayette Jan 7 · Dec 19
- Pleasant Hill Jan 7 · Dec 19
- Alamo Mar 8 · Dec 22
- Concord Jan 9 · Dec 14
- Diablo Mar 8 · Dec 22
- Orinda Jan 3 · Jan 1
- Martinez Feb 28 · Nov 22
- Moraga Mar 8 · Dec 22
Frequently asked questions
When is the last frost in Walnut Creek, CA?
The median last spring frost in Walnut Creek, CA is January 7. There is still about a 10% chance of frost after February 1, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Walnut Creek, CA?
The median first fall frost is December 19, with about a 10% chance of frost before December 1.
How long is the growing season in Walnut Creek, CA?
About 346 days between the median last spring frost and first fall frost.
What planting zone is Walnut Creek, CA?
Walnut Creek, CA is in USDA hardiness zone 9b.