Frost dates for Mountain House, 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 19
typical year
Safe to plant
February 17
frost is over in 9 of 10 years
First fall frost
December 10
typical year
Growing season
330 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 22 – Jan 5 | – |
| Spinach | – | Dec 8 – 29 | Oct 15 – 29 |
| Lettuce | – | Dec 22 – Jan 12 | Oct 15 – 29 |
| Radishes | – | Dec 22 – Feb 2 | Oct 29 – Nov 12 |
| Onions | – | Dec 22 – Jan 5 | – |
| Potatoes | – | Dec 29 – Jan 12 | – |
| Carrots | – | Dec 29 – Jan 19 | Sep 17 – Oct 1 |
| Beets | – | Dec 22 – Jan 5 | Oct 1 – 15 |
| Kale | Nov 10 – 24 | Dec 22 – Jan 5 | Oct 1 – 15 |
| Broccoli | Nov 10 – 24 | Jan 5 – 19 | Oct 1 – 15 |
| Cabbage | Oct 27 – Nov 10 | Dec 22 – Jan 5 | Oct 1 – 15 |
| Garlic | – | – | Oct 29 – Nov 19 |
| Warm-season crops | |||
| Tomatoes | Dec 23 – Jan 6 | Feb 17 – Mar 3 | – |
| Peppers | Dec 16 – 30 | Feb 24 – Mar 10 | – |
| Cucumbers | – | Feb 17 – Mar 10 | – |
| Zucchini | – | Feb 17 – Mar 17 | – |
| Pumpkins | – | Feb 17 – Mar 10 | – |
| Green beans | – | Feb 17 – Oct 1 | – |
| Sweet corn | – | Feb 17 – Mar 17 | – |
| Basil | Jan 13 – 27 | Feb 24 – Mar 3 | – |
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 17 | January 19 | December 25 |
| Fall frost before | November 26 | December 10 | January 7 |
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 January 1 (January 22 in a late year), and the first one in fall around December 22.
Towns that use these dates
This is the nearest NOAA station with frost records for 1 town.
Mountain House
Where these dates come from
NOAA weather station TRACY PUMPING PLT, CA US (USC00049001), 1991–2020 climate normals. It's the nearest station for 4 zip codes, all within 9 miles:
94505, 94514, 95377, 95391
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.