ASLA Oregon LANDbytes FEBRUARY 2012 Feature:
Updated Plant Hardiness Zones
By Rebecca Wahlstrom
Updated for the first time since 1990, the 2012 USDA Plant Hardiness Zone Map shows a significant warming shift to the north and adds two more zones to the map. Using a longer period of data collection and more sophisticated technology, the USDA Agricultural Research Service and the OSU PRISM Climate Group have produced a more accurate representation of the hardiness zones in the United States.
One can access the maps and data at the USDA website; planthardiness.ars.usda.gov/PHZMWeb/InteractiveMap.aspx . There you can find interactive maps and download GIS information (shapefile and raster grid formats). To take the guesswork out of finding the correct zone, you have the option of typing in a zip code to give you the exact hardiness zone. There are also static maps if one doesn’t want all the bells and whistles, or your computer service is minimal. The old days of having the USDA send you a poster are gone, but maps are available for free downloading and printing. Check it out!