As climate change warms the Earth, plant hardiness zones are shifting northward. The U.S. Department of Agriculture has updated its plant hardiness zone map to reflect these changes, providing valuable information for home gardeners across the country. The hardiness zones defined by the USDA begin with zone 1, which is the coldest and end with zone 13, which encompasses the warmest growing conditions.
The USDA Plant Hardiness Zone Map helps home gardeners pick which plants to grow. But recently, roughly a quarter of the country has moved into a warmer zone, leading to new opportunities for growing a wider variety of plants. Most longtime New Jerseyans – especially gardeners and growers – have noticed that winters have gotten milder over the last few decades, indicating a shift in hardiness zones.
Wisconsin is now made up of zones 3b through 6a, with the warmest zone 6a being completely new to the state. It represents a small sliver of the state where gardeners can experiment with plants that were previously not suitable for the climate. The new USDA plant hardiness zone map has been updated with Todd Rounsaville, showing the changes that have occurred and providing valuable information for gardeners.