Fertile, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1.3 °C (low) to 9.8 °C (high). Annual precipitation averages 622.1 Millimeters. Fertile is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -19.2 °C | -9.2 °C | 19.3 mm |
| February | -17.6 °C | -6.6 °C | 19.56 mm |
| March | -9.4 °C | 1 °C | 25.4 mm |
| April | -1.2 °C | 10.4 °C | 35.31 mm |
| May | 5.8 °C | 18.4 °C | 78.74 mm |
| June | 12.1 °C | 23.6 °C | 108.97 mm |
| July | 14.1 °C | 26.1 °C | 85.34 mm |
| August | 12.6 °C | 25.6 °C | 76.45 mm |
| September | 7.7 °C | 20.6 °C | 72.14 mm |
| October | 1 °C | 11.9 °C | 57.15 mm |
| November | -7.1 °C | 2.1 °C | 20.83 mm |
| December | -14.8 °C | -5.8 °C | 22.86 mm |
| Annual | -1.3 °C | 9.8 °C | 622.05 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -34.4°C to -31.7°C |
| Plant Hardiness Zone - 2012 | Zone 3b : -37.2°C to -34.4°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |