USDA Hardiness Zone 10a
Frost Dates for 91345 — Mission Hills, California
Averages from Northridge Cal State, Ca US, the nearest reporting station, 4 miles away.
Plant tender crops after January 2, and expect the first autumn freeze around January 1. That leaves about 365 frost-free days.
- Last spring frost
- January 2
- First fall frost
- January 1
- Growing season
- 365 days
- Hardiness zone
- 10a
50% probability
50% probability
frost-free
30 to 35°F annual low
Planting calendar for 91345
| When | What to do |
|---|---|
| October 24 – November 7 | Start peppers and aubergines indoors They need eight to ten weeks under lights before they can go out. |
| November 7 – November 21 | Start tomatoes indoors Six to eight weeks gives a transplant big enough to set fruit early. |
| December 5 – December 19 | Sow peas, spinach, lettuce, radish outdoors These tolerate light frost and prefer to germinate in cool soil. |
| January 2 onward | Transplant tomatoes, peppers, basil, squash, cucumbers The average last freeze has passed — still watch the actual forecast. |
| by October 9 | Sow the autumn crop of carrots, beets and brassicas They need about twelve weeks to size up before growth stops. |
| by December 18 | Harvest tender crops, or be ready to cover them A first freeze two weeks early is well within normal variation. |
| January 1 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 2 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Mission Hills, California are past their last freeze. Harvest before January 1, which leaves roughly 365 frost-free days.
ZIP 91345 sits in USDA hardiness zone 10a, meaning the average coldest night of the year falls between 30 to 35°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.