Plantsville, Connecticut has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5 °C (low) to 16 °C (high). Annual precipitation averages 1307.6 Millimeters. Plantsville is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.1 °C | 2.6 °C | 96.77 mm |
| February | -6.4 °C | 3.9 °C | 86.36 mm |
| March | -2.2 °C | 8.3 °C | 116.84 mm |
| April | 3.4 °C | 15.2 °C | 106.43 mm |
| May | 9.1 °C | 21.2 °C | 102.11 mm |
| June | 14.3 °C | 25.8 °C | 117.6 mm |
| July | 17.4 °C | 28.9 °C | 106.93 mm |
| August | 16.5 °C | 27.9 °C | 105.16 mm |
| September | 12.4 °C | 24.1 °C | 114.81 mm |
| October | 5.9 °C | 17.4 °C | 134.11 mm |
| November | 0.6 °C | 11.1 °C | 101.09 mm |
| December | -3.9 °C | 5.4 °C | 119.38 mm |
| Annual | 5 °C | 16 °C | 1307.59 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |