USDA Hardiness Zone 9b
Frost Dates for 94549 — Lafayette, California
Averages from Concord Wwtp, Ca US, the nearest reporting station, 6.6 miles away.
Plant tender crops after January 7, and expect the first autumn freeze around December 19. That leaves about 346 frost-free days.
- Last spring frost
- January 7
- First fall frost
- December 19
- Growing season
- 346 days
- Hardiness zone
- 9b
50% probability
50% probability
frost-free
25 to 30°F annual low
Planting calendar for 94549
| When | What to do |
|---|---|
| October 29 – November 12 | Start peppers and aubergines indoors They need eight to ten weeks under lights before they can go out. |
| November 12 – November 26 | Start tomatoes indoors Six to eight weeks gives a transplant big enough to set fruit early. |
| December 10 – December 24 | Sow peas, spinach, lettuce, radish outdoors These tolerate light frost and prefer to germinate in cool soil. |
| January 7 onward | Transplant tomatoes, peppers, basil, squash, cucumbers The average last freeze has passed — still watch the actual forecast. |
| by September 26 | Sow the autumn crop of carrots, beets and brassicas They need about twelve weeks to size up before growth stops. |
| by December 5 | Harvest tender crops, or be ready to cover them A first freeze two weeks early is well within normal variation. |
| December 19 onward | Plant garlic, mulch beds, lift tender bulbs Garlic wants a cold spell; bare soil loses structure over winter. |
What these dates mean
Wait until after January 7 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Lafayette, California are past their last freeze. Harvest before December 19, which leaves roughly 346 frost-free days.
ZIP 94549 sits in USDA hardiness zone 9b, meaning the average coldest night of the year falls between 25 to 30°F. Zone decides what survives the winter; frost dates decide when to plant each spring. They are different questions, and a plant can pass one and fail the other.
These are thirty-year NOAA averages for 1991–2020, not a forecast. Any individual year can frost two to three weeks either side of these dates, so check the actual forecast before planting out.