Madeline Wimmer, Extension Educator, Fruit Production Image: Young grape shoots damaged by late spring frost (May 11th, 2021). Photos taken by Madeline Wimmer. Cold stress and frost damage have the potential to impact perennial fruit crops during different times of the year, and springtime in the Upper Midwest is no exception. While cold stress can happen at warmer temperatures, frost occurs when ambient temperatures fall below freezing (32 ° F). When a spring frost happens, it can harm vegetation, and negatively impact bloom and fruit set. This is problematic recognizing that many perennial fruits exit dormancy and begin growing in Minnesota before the threat of spring frost has passed. Crop loss due to frost damage can be devastating and many strategies that help annual crop growers (e.g., delayed planting) are not usually possible for perennial crops. What happens when dormant chilling requirements are ahead of schedule? During winter seasons when more chilling hours (total hours d
We've developed a new webpage for growers to learn about projected climate changes in Minnesota, and strategies for resilience that are specific to Minnesota, and to vegetable farming. Climate models project the following about our future climate in Minnesota by the years 2040-2060: Increased average precipitation statewide in spring, winter and fall. No change or a slight decrease in average summer precipitation. Increased frequency of wet and dry extremes such as heavy rains (more than 2 inches) and drought statewide. Longer periods between wet and dry events. Warmer average temperatures year-round, with the greatest change in winter average temperature. Increased number of days at or above 90°F, increased number of nights at or above 70°F. Higher intensity of drought due to higher temperatures. Decreased number of days at or below 32°F, decreased number of nights at or below 0°F. Later freeze dates, earlier thaw dates. If you are applying for funds for climate mitigation practic