Frost dates for Stewart Mtn Dam, AZ
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
February 13
typical year
Safe to plant
March 8
frost is over in 9 of 10 years
First fall frost
December 5
typical year
Growing season
295 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 | – | Jan 16 – 30 | – |
| Spinach | – | Jan 2 – 23 | Oct 10 – 24 |
| Lettuce | – | Jan 16 – Feb 6 | Oct 10 – 24 |
| Radishes | – | Jan 16 – Feb 27 | Oct 24 – Nov 7 |
| Onions | – | Jan 16 – 30 | – |
| Potatoes | – | Jan 23 – Feb 6 | – |
| Carrots | – | Jan 23 – Feb 13 | Sep 12 – 26 |
| Beets | – | Jan 16 – 30 | Sep 26 – Oct 10 |
| Kale | Dec 5 – 19 | Jan 16 – 30 | Sep 26 – Oct 10 |
| Broccoli | Dec 5 – 19 | Jan 30 – Feb 13 | Sep 26 – Oct 10 |
| Cabbage | Nov 21 – Dec 5 | Jan 16 – 30 | Sep 26 – Oct 10 |
| Garlic | – | – | Oct 24 – Nov 14 |
| Warm-season crops | |||
| Tomatoes | Jan 11 – 25 | Mar 8 – 22 | – |
| Peppers | Jan 4 – 18 | Mar 15 – 29 | – |
| Cucumbers | – | Mar 8 – 29 | – |
| Zucchini | – | Mar 8 – Apr 5 | – |
| Pumpkins | – | Mar 8 – 29 | – |
| Green beans | – | Mar 8 – Sep 26 | – |
| Sweet corn | – | Mar 8 – Apr 5 | – |
| Basil | Feb 1 – 15 | Mar 15 – 22 | – |
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 8 | February 13 | January 10 |
| Fall frost before | November 18 | December 5 | December 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 January 18 (February 20 in a late year), and the first one in fall around December 19.
Where these dates come from
NOAA weather station STEWART MTN DAM, AZ US (USC00028214), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 9 miles:
85215, 85264
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.