Frost dates for Clarion, PA
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
May 9
typical year
Safe to plant
May 24
frost is over in 9 of 10 years
First fall frost
October 11
typical year
Growing season
154 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 | – | Apr 11 – 25 | – |
| Spinach | – | Mar 28 – Apr 18 | Aug 16 – 30 |
| Lettuce | – | Apr 11 – May 2 | Aug 16 – 30 |
| Radishes | – | Apr 11 – May 23 | Aug 30 – Sep 13 |
| Onions | – | Apr 11 – 25 | – |
| Potatoes | – | Apr 18 – May 2 | – |
| Carrots | – | Apr 18 – May 9 | Jul 19 – Aug 2 |
| Beets | – | Apr 11 – 25 | Aug 2 – 16 |
| Kale | Feb 28 – Mar 14 | Apr 11 – 25 | Aug 2 – 16 |
| Broccoli | Feb 28 – Mar 14 | Apr 25 – May 9 | Aug 2 – 16 |
| Cabbage | Feb 14 – 28 | Apr 11 – 25 | Aug 2 – 16 |
| Garlic | – | – | Aug 30 – Sep 20 |
| Warm-season crops | |||
| Tomatoes | Mar 29 – Apr 12 | May 24 – Jun 7 | – |
| Peppers | Mar 22 – Apr 5 | May 31 – Jun 14 | – |
| Cucumbers | – | May 24 – Jun 14 | – |
| Zucchini | – | May 24 – Jun 21 | – |
| Pumpkins | – | May 24 – Jun 14 | – |
| Green beans | – | May 24 – Aug 2 | – |
| Sweet corn | – | May 24 – Jun 21 | – |
| Basil | Apr 19 – May 3 | May 31 – Jun 7 | – |
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 24 | May 9 | April 24 |
| Fall frost before | September 30 | October 11 | October 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 April 29 (May 15 in a late year), and the first one in fall around October 24.
Towns that use these dates
This is the nearest NOAA station with frost records for 13 towns.
Clarion, Knox, Rimersburg, East Brady, Parker, Sligo, Emlenton, Strattanville, Summerville, Shippenville, St. Petersburg, Foxburg, Callensburg
Where these dates come from
NOAA weather station CLARION 3 SW, PA US (USC00361485), 1991–2020 climate normals. It's the nearest station for 14 zip codes, all within 14 miles:
15829, 16036, 16049, 16054, 16213, 16214, 16232, 16248, 16254, 16255, 16258, 16331, 16334, 16373
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.