When the First Frost Ran Away Like Elsa

    As time progresses, a worrying trend has been recognized: the inconsistency of the First Frost. Frost dates are the day of the year when it is calculated to be 50% likely that the temperature will dip below freezing, resulting in frost on the ground, according to Morning Chores. In spring, we have a ‘last frost date,’ and in the fall, we have a ‘first frost date.’ The Last Frost date essentially signifies when planting begins, and the First Frost date signals when harvest season ends. Recently we’ve been seeing the First Frost date getting pushed back. The Fourth National Climate Assessment released by the Trump administration in 2018 reported that “the length of the frost-free season, from the last freeze in spring to the first freeze of autumn, has increased for all regions since the early 1900s.” Why is there an increase? The conclusion that scientists have come to is that this is largely due to Global Warming. “This is one of the clearest signs of not only the changing climate but … its impact on our systems,” said Jeremy Hoffman on the topic of moving frost dates (a chief scientist at the Science Museum of Virginia). In Des Moines, Iowa, one of the earliest First Frosts recorded occurred on September 8-9 in 1883. Now the First Frost tends to fall in late October. This seems good, right? Why wouldn’t farmers want a lengthened growing season? Well, with longer growing seasons, the populations of insects are increasing, the mortality is lower, they can produce more generations a year, and that potentially presents a problem for agriculture and plants in general.

Additionally, we usually don’t have to worry about weeds at the beginning of  October since they die off due to the cold, even though they still present a problem in late October. This also creates issues in planning crops. With the unpredictability of the First Frost date, it becomes increasingly difficult to know when to stop plants and when to start them since some like warmer weather while others thrive in the colder months. There is no true solution to this issue other than slowing down climate change. For us, it becomes increasingly difficult to know when to solarize our soil (read more in the “Tucking in our Soil Beds for Winter” installment) and when to start plants. Will we get the happy ending Frozen had when Elsa returned, or will our First Frost Date continue to be pushed back?