In formerly cold Boston, southern stalwarts like camellias and magnolia trees may suddenly be able to grow without damage from frost.
For the first time in ten years, the U.S. Department of Agriculture’s “plant hardiness zone map” was updated on Wednesday, illustrating the effects of climate change on yards and gardens around the nation.
Changes in the climate aren’t even; for instance, the Midwest warmed more than the Southeast. However, the map will provide gardeners with fresh advice regarding which plants, veggies, and flowers are most likely to flourish in a specific area.
The lowest predicted winter temperature in a particular area is one of the map’s most crucial figures since it helps identify the plants that might make it through the season.
It is computed by taking the 30-year average of the lowest winter temperatures.
According to Chris Daly, a researcher at Oregon State University’s PRISM Climate Group, which works with the USDA’s Agricultural Research Service to produce the map, the lowest likely winter temperature overall across the lower 48 states is 2.5 degrees (1.4 degrees Celsius) warmer than when the last map was published in 2012.
Aside from the map project, Richard Primack, a plant ecologist at Boston University, stated that “half the U.S. has shifted to a slightly warmer climatic zone than it was 10 years ago.” That was dubbed “a very striking finding” by him.
In his own yard, Primack reported observing changes: the fig trees are thriving without substantial steps to shield them from the winter cold. He has also seen southern magnolia trees that have survived the last several winters without suffering frost damage, as well as camellias in a botanical garden near Boston. In general, warmer, more southern temperatures are linked to all of these species.
According to Primack, nighttime and winter temperatures are rising more quickly than summer and daylight temperatures, which is why the lowest winter temperature is fluctuating more quickly than the U.S.
It can be difficult for plants and producers to adapt as the environment changes.
Theresa Crimmins, who researches climate change and growing seasons at the University of Arizona and was not involved in making the map, added, “There are a lot of downsides to the warmer winter temperatures, too.” “Insects that spread disease, such as ticks and mosquitoes, experience less severe die-backs when winter temperatures are milder.”
She also mentioned that plants that used to grow well in certain areas may die due to hotter, drier summers.
“Planting plants that aren’t currently adapted for your location would be a bad idea,” the speaker stated.