Frost dates for Saguaro Np, 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
January 26
typical year
Safe to plant
February 25
frost is over in 9 of 10 years
First fall frost
December 16
typical year
Growing season
326 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 29 – Jan 12 | – |
| Spinach | – | Dec 15 – Jan 5 | Oct 21 – Nov 4 |
| Lettuce | – | Dec 29 – Jan 19 | Oct 21 – Nov 4 |
| Radishes | – | Dec 29 – Feb 9 | Nov 4 – 18 |
| Onions | – | Dec 29 – Jan 12 | – |
| Potatoes | – | Jan 5 – 19 | – |
| Carrots | – | Jan 5 – 26 | Sep 23 – Oct 7 |
| Beets | – | Dec 29 – Jan 12 | Oct 7 – 21 |
| Kale | Nov 17 – Dec 1 | Dec 29 – Jan 12 | Oct 7 – 21 |
| Broccoli | Nov 17 – Dec 1 | Jan 12 – 26 | Oct 7 – 21 |
| Cabbage | Nov 3 – 17 | Dec 29 – Jan 12 | Oct 7 – 21 |
| Garlic | – | – | Nov 4 – 25 |
| 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 7 | – |
| 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 26 | December 24 |
| Fall frost before | November 26 | December 16 | January 17 |
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 7 (February 9 in a late year), and the first one in fall around December 28.
Where these dates come from
NOAA weather station SAGUARO NP, AZ US (USC00027398), 1991–2020 climate normals. It's the nearest station for 6 zip codes, all within 12 miles:
85641, 85710, 85730, 85747, 85748, 85749
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.