Frost dates for Palomar Mtn Obsy, 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
April 29
typical year
Safe to plant
May 29
frost is over in 9 of 10 years
First fall frost
November 18
typical year
Growing season
201 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 | – | Apr 1 – 15 | – |
| Spinach | – | Mar 18 – Apr 8 | Sep 23 – Oct 7 |
| Lettuce | – | Apr 1 – 22 | Sep 23 – Oct 7 |
| Radishes | – | Apr 1 – May 13 | Oct 7 – 21 |
| Onions | – | Apr 1 – 15 | – |
| Potatoes | – | Apr 8 – 22 | – |
| Carrots | – | Apr 8 – 29 | Aug 26 – Sep 9 |
| Beets | – | Apr 1 – 15 | Sep 9 – 23 |
| Kale | Feb 18 – Mar 4 | Apr 1 – 15 | Sep 9 – 23 |
| Broccoli | Feb 18 – Mar 4 | Apr 15 – 29 | Sep 9 – 23 |
| Cabbage | Feb 4 – 18 | Apr 1 – 15 | Sep 9 – 23 |
| Garlic | – | – | Oct 7 – 28 |
| Warm-season crops | |||
| Tomatoes | Apr 3 – 17 | May 29 – Jun 12 | – |
| Peppers | Mar 27 – Apr 10 | Jun 5 – 19 | – |
| Cucumbers | – | May 29 – Jun 19 | – |
| Zucchini | – | May 29 – Jun 26 | – |
| Pumpkins | – | May 29 – Jun 19 | – |
| Green beans | – | May 29 – Sep 9 | – |
| Sweet corn | – | May 29 – Jun 26 | – |
| Basil | Apr 24 – May 8 | Jun 5 – 12 | – |
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 | May 29 | April 29 | April 2 |
| Fall frost before | October 27 | November 18 | December 8 |
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 April 5 (May 5 in a late year), and the first one in fall around December 6.
Where these dates come from
NOAA weather station PALOMAR MTN OBSY, CA US (USC00046657), 1991–2020 climate normals. It's the nearest station for 4 zip codes, all within 15 miles:
92060, 92061, 92536, 92539
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.