The Earth’s climate is changing. This is not news to most gardeners. We see it in our backyards, our gardens and if we’ve been gardening a while, with the USDA hardiness zones update in 2012. When the map was redrawn, almost half of the continental US saw a change in their hardiness zone. Many believe this was due to climate change. What is the USDA Hardiness Zone Map First published in 1960 by the US Department of Agriculture, the hardiness zone map depicts the average annual minimum temperature for an area. The first map was divided into 10 zones with each zone representing a 10 degree (Fahrenheit) temperature range. For instance, the average annual minimum temperature for zone one is -50 to -60 degrees F. or -51.1 to -45.6 degrees C. Since that time USDA Hardiness Zone map changes have included the addition of zones 11-13. Each numbered zone has […]
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