Frost dates in Hartwick, IA
The average last spring frost in Hartwick is around April 30 and the first fall frost is around October 5. That gives Hartwick an average growing season of about 158 days.
Last spring frost
| Early (10% chance after) | April 21 |
|---|---|
| Average (50%) | April 30 |
| Late (90%) | May 6 |
First fall frost
| Early (10%) | September 21 |
|---|---|
| Average (50%) | October 5 |
| Late (90% chance before) | October 10 |