Frost dates for Simi Valley, CA
When the last spring frost and first fall frost usually come, and when to plant, from 30 years of NOAA weather records.
Last spring frost
January 24
typical year
Safe to plant
March 5
frost is over in 9 of 10 years
First fall frost
December 15
typical year
Growing season
329 days
frost-free, typical year
Frost watch this week
Tonight's and the next six nights' lows from the National Weather Service forecast for the station's location. Frost: 32°F or colder. Possible frost: 33–36°F, mostly in low spots on clear, still nights.
When to plant
Counted from this page's frost dates. Warm-season crops wait for the safe-to-plant date.
| Crop | Start indoors | Plant outside | Fall planting |
|---|---|---|---|
| Cool-season crops | |||
| Peas | – | Dec 27 – Jan 10 | – |
| Spinach | – | Dec 13 – Jan 3 | Oct 20 – Nov 3 |
| Lettuce | – | Dec 27 – Jan 17 | Oct 20 – Nov 3 |
| Radishes | – | Dec 27 – Feb 7 | Nov 3 – 17 |
| Onions | – | Dec 27 – Jan 10 | – |
| Potatoes | – | Jan 3 – 17 | – |
| Carrots | – | Jan 3 – 24 | Sep 22 – Oct 6 |
| Beets | – | Dec 27 – Jan 10 | Oct 6 – 20 |
| Kale | Nov 15 – 29 | Dec 27 – Jan 10 | Oct 6 – 20 |
| Broccoli | Nov 15 – 29 | Jan 10 – 24 | Oct 6 – 20 |
| Cabbage | Nov 1 – 15 | Dec 27 – Jan 10 | Oct 6 – 20 |
| Garlic | – | – | Nov 3 – 24 |
| Warm-season crops | |||
| Tomatoes | Jan 8 – 22 | Mar 5 – 19 | – |
| Peppers | Jan 1 – 15 | Mar 12 – 26 | – |
| Cucumbers | – | Mar 5 – 26 | – |
| Zucchini | – | Mar 5 – Apr 2 | – |
| Pumpkins | – | Mar 5 – 26 | – |
| Green beans | – | Mar 5 – Oct 6 | – |
| Sweet corn | – | Mar 5 – Apr 2 | – |
| Basil | Jan 29 – Feb 12 | Mar 12 – 19 | – |
Onions: from sets. Green beans: until 10 weeks before the first fall frost. Garlic: harvest next summer.
The year at a glance
Start indoors Plant outside Fall planting
The chance of frost, by date
| 1 year in 10 | Half of years | 9 years in 10 | |
|---|---|---|---|
| Spring frost after | March 5 | January 24 | December 21 |
| Fall frost before | November 27 | December 15 | January 26 |
Frost here means 32°F or colder. Read across: in 1 year in 10, spring frost carries on past the first date, which is why that date is the safe-to-plant date.
Hard freeze (28°F)
A hard freeze kills most garden plants, even hardy ones. The last one in spring usually comes around December 31 (February 1 in a late year), and the first one in fall around December 26.
Towns that use these dates
This is the nearest NOAA station with frost records for 7 towns.
Simi Valley, Santa Monica, Calabasas, Agoura Hills, Malibu, Westlake Village, Hidden Hills
Where these dates come from
NOAA weather station WOODLAND HILLS PIERCE COLLEGE, CA US (USC00049785), 1991–2020 climate normals. It's the nearest station for 26 zip codes, all within 14 miles:
90049, 90263, 90272, 90290, 90291, 90401, 90402, 90403, 90404, 90405, 91301, 91302, 91303, 91304, 91306, 91307, 91316, 91335, 91356, 91362, 91364, 91367, 91371, 91377, 93064, 93065
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.