Frost dates for Riverside, 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 9
typical year
Safe to plant
February 25
frost is over in 9 of 10 years
First fall frost
December 25
typical year
Growing season
353 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 12 – 26 | – |
| Spinach | – | Nov 28 – Dec 19 | Oct 30 – Nov 13 |
| Lettuce | – | Dec 12 – Jan 2 | Oct 30 – Nov 13 |
| Radishes | – | Dec 12 – Jan 23 | Nov 13 – 27 |
| Onions | – | Dec 12 – 26 | – |
| Potatoes | – | Dec 19 – Jan 2 | – |
| Carrots | – | Dec 19 – Jan 9 | Oct 2 – 16 |
| Beets | – | Dec 12 – 26 | Oct 16 – 30 |
| Kale | Oct 31 – Nov 14 | Dec 12 – 26 | Oct 16 – 30 |
| Broccoli | Oct 31 – Nov 14 | Dec 26 – Jan 9 | Oct 16 – 30 |
| Cabbage | Oct 17 – 31 | Dec 12 – 26 | Oct 16 – 30 |
| Garlic | – | – | Nov 13 – Dec 4 |
| Warm-season crops | |||
| Tomatoes | Dec 31 – Jan 14 | Feb 25 – Mar 11 | – |
| Peppers | Dec 24 – Jan 7 | Mar 4 – 18 | – |
| Cucumbers | – | Feb 25 – Mar 18 | – |
| Zucchini | – | Feb 25 – Mar 25 | – |
| Pumpkins | – | Feb 25 – Mar 18 | – |
| Green beans | – | Feb 25 – Oct 16 | – |
| Sweet corn | – | Feb 25 – Mar 25 | – |
| Basil | Jan 21 – Feb 4 | Mar 4 – 11 | – |
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 | February 25 | January 9 | December 16 |
| Fall frost before | December 1 | December 25 | January 27 |
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 (January 16 in a late year), and the first one in fall around December 29.
Towns that use these dates
This is the nearest NOAA station with frost records for 1 town.
Riverside
Where these dates come from
NOAA weather station RIVERSIDE FIRE STN 3, CA US (USC00047470), 1991–2020 climate normals. It's the nearest station for 3 zip codes, all within 5 miles:
92504, 92506, 92508
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.