Shifting Planting Zones

The document analyzes how warming average annual minimum temperatures in the U.S. are shifting plant hardiness zones northward, affecting the geographic range of crops, invasive species, and pests. Based on an analysis of 242 U.S. locations from 1951 to 2022, it finds that 95% of these locations experienced warming, with some cities seeing significant zone shifts. This trend may expand the range of high-value crops but also facilitates the spread of invasive species like Kudzu and the brown marmorated stink bug.

• Plant hardiness zones in the contiguous U.S. have shifted north over the three most recent 30-year normal periods as the coldest times of the year warm.
• An analysis of 242 U.S. locations showed that average annual minimum temperatures warmed in 231 (95%) of those locations. Between the 1951-1980 baseline and the 1993-2022 period, these temperatures increased by 3.1°F on average across all 242 locations, while the 231 warming locations increased by 3.3°F on average.
• Half of the 242 analyzed locations experienced an increase in their plant hardiness zone at some point during the study period. The most significant increases in average annual minimum temperatures between 1951-1980 and 1993-2022 occurred in Reno, Nev. (9.3°F), Anchorage, Alaska (8.7°F), Las Vegas, Nev. (8.6°F), Las Cruces, Texas (8°F), and Juneau, Alaska (7.8°F).
• Warming temperatures allow plants and insects to expand into new areas. This includes the potential for high-value crops like almonds, oranges, and kiwis to move north, but also the expansion of invasive species such as Kudzu and the brown marmorated stink bug.
• If carbon pollution continues, annual minimum temperatures could shift north at a rate of approximately 13 miles per decade, with the fastest shifts expected in the Midwest and the northern Great Plains.

APA

Climate Central (2023). Shifting Planting Zones. https://www.climatecentral.org/climate-matters/shifting-planting-zones-2023

Chicago

Climate Central. Shifting Planting Zones. 2023. https://www.climatecentral.org/climate-matters/shifting-planting-zones-2023.

Wikipedia

{{cite report |author=Climate Central |title=Shifting Planting Zones |date=5 April 2023 |url=https://www.climatecentral.org/climate-matters/shifting-planting-zones-2023 |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{climatecentral2023shifting, author = {{Climate Central}}, title = {{Shifting Planting Zones}}, institution = {Climate Central}, year = {2023}, month = apr, url = {https://www.climatecentral.org/climate-matters/shifting-planting-zones-2023}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }