Global warming is a hot topic in the news, and with the balmy weather much of the nation is enjoying this winter, many people are becoming convinced that this phenomenon is real. In light of the warming trend, one of the tools gardeners employ to choose the right plants for their yards is being updated.
The USDA Hardiness Zone map is the standard most nurseries and gardeners use to determine if a plant will survive in their zone. The current map lists 11 zones based on average annual winter minimum temperatures from 1974 to 1986. It was last updated in 1990.
The U.S. Government has yet to officially update the map to reflect the changes in the climate in the last decade and a half, however other groups have taken the initiative. The Arbor Day Foundation has recently published an updated version of the hardiness zone map that incorporates 15 years of data collected from the National Oceanic and Atmospheric Administration's 5,000 National Climatic Data Center cooperative stations across the United States.
The new zone map redraws the U.S. Hardiness zone map and illustrates the differences between the 1990 and 2006 maps. As expected, most regions saw a shift of one, and sometimes two, zones warmer when compared to the 1990 map.
To check out the new map, go to: Arbor Day Foundation.