Frost dates for Marion, IA
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 28
typical year
Safe to plant
May 13
frost is over in 9 of 10 years
First fall frost
October 12
typical year
Growing season
166 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 31 – Apr 14 | – |
| Spinach | – | Mar 17 – Apr 7 | Aug 17 – 31 |
| Lettuce | – | Mar 31 – Apr 21 | Aug 17 – 31 |
| Radishes | – | Mar 31 – May 12 | Aug 31 – Sep 14 |
| Onions | – | Mar 31 – Apr 14 | – |
| Potatoes | – | Apr 7 – 21 | – |
| Carrots | – | Apr 7 – 28 | Jul 20 – Aug 3 |
| Beets | – | Mar 31 – Apr 14 | Aug 3 – 17 |
| Kale | Feb 17 – Mar 3 | Mar 31 – Apr 14 | Aug 3 – 17 |
| Broccoli | Feb 17 – Mar 3 | Apr 14 – 28 | Aug 3 – 17 |
| Cabbage | Feb 3 – 17 | Mar 31 – Apr 14 | Aug 3 – 17 |
| Garlic | – | – | Aug 31 – Sep 21 |
| Warm-season crops | |||
| Tomatoes | Mar 18 – Apr 1 | May 13 – 27 | – |
| Peppers | Mar 11 – 25 | May 20 – Jun 3 | – |
| Cucumbers | – | May 13 – Jun 3 | – |
| Zucchini | – | May 13 – Jun 10 | – |
| Pumpkins | – | May 13 – Jun 3 | – |
| Green beans | – | May 13 – Aug 3 | – |
| Sweet corn | – | May 13 – Jun 10 | – |
| Basil | Apr 8 – 22 | May 20 – 27 | – |
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 | May 13 | April 28 | April 14 |
| Fall frost before | September 29 | October 12 | October 25 |
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 April 17 (May 2 in a late year), and the first one in fall around October 22.
Towns that use these dates
This is the nearest NOAA station with frost records for 8 towns.
Marion, Hiawatha, Mount Vernon, Robins, Palo, Springville, Alburnett, Bertram
Where these dates come from
NOAA weather station CEDAR RAPIDS #1, IA US (USC00131319), 1991–2020 climate normals. It's the nearest station for 11 zip codes, all within 11 miles:
52202, 52233, 52302, 52314, 52324, 52328, 52341, 52401, 52402, 52403, 52411
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.