Frost dates in Bertha, MN
The average last spring frost in Bertha is around May 12 and the first fall frost is around September 24. That gives Bertha an average growing season of about 135 days.
Last spring frost
| Early (10% chance after) | April 25 |
|---|---|
| Average (50%) | May 12 |
| Late (90%) | June 1 |
First fall frost
| Early (10%) | September 12 |
|---|---|
| Average (50%) | September 24 |
| Late (90% chance before) | October 8 |