Frost dates for Arnold, MO
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 9
typical year
Safe to plant
April 25
frost is over in 9 of 10 years
First fall frost
October 26
typical year
Growing season
197 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 | – | Mar 12 – 26 | – |
| Spinach | – | Feb 26 – Mar 19 | Aug 31 – Sep 14 |
| Lettuce | – | Mar 12 – Apr 2 | Aug 31 – Sep 14 |
| Radishes | – | Mar 12 – Apr 23 | Sep 14 – 28 |
| Onions | – | Mar 12 – 26 | – |
| Potatoes | – | Mar 19 – Apr 2 | – |
| Carrots | – | Mar 19 – Apr 9 | Aug 3 – 17 |
| Beets | – | Mar 12 – 26 | Aug 17 – 31 |
| Kale | Jan 29 – Feb 12 | Mar 12 – 26 | Aug 17 – 31 |
| Broccoli | Jan 29 – Feb 12 | Mar 26 – Apr 9 | Aug 17 – 31 |
| Cabbage | Jan 15 – 29 | Mar 12 – 26 | Aug 17 – 31 |
| Garlic | – | – | Sep 14 – Oct 5 |
| Warm-season crops | |||
| Tomatoes | Feb 28 – Mar 14 | Apr 25 – May 9 | – |
| Peppers | Feb 21 – Mar 7 | May 2 – 16 | – |
| Cucumbers | – | Apr 25 – May 16 | – |
| Zucchini | – | Apr 25 – May 23 | – |
| Pumpkins | – | Apr 25 – May 16 | – |
| Green beans | – | Apr 25 – Aug 17 | – |
| Sweet corn | – | Apr 25 – May 23 | – |
| Basil | Mar 21 – Apr 4 | May 2 – 9 | – |
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 | April 25 | April 9 | March 25 |
| Fall frost before | October 14 | October 26 | November 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 March 31 (April 15 in a late year), and the first one in fall around November 5.
Towns that use these dates
This is the nearest NOAA station with frost records for 15 towns.
Arnold, Festus, Waterloo, IL, De Soto, Pevely, Herculaneum, Crystal City, Hillsboro, Valmeyer, IL, Olympian Village, Cedar Hill Lakes, Scotsdale, Maeystown, IL, Kimmswick, Fults, IL
Where these dates come from
NOAA weather station FESTUS, MO US (USC00232850), 1991–2020 climate normals. It's the nearest station for 19 zip codes, all within 17 miles:
62244, 62256, 62295, 62298, 63010, 63012, 63016, 63019, 63020, 63023, 63028, 63047, 63048, 63050, 63051, 63052, 63053, 63070, 63627
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.