2012 USDA Plant Hardiness Zone Map -
http://planthardiness.ars.usda.gov/PHZMWeb/
"For the first time, the map is available as an interactive GIS-based
map, for which a broadband Internet connection is recommended, and as
static images for those with slower Internet access. Users may also
simply type in a ZIP Code and find the hardiness zone for that area.
"No posters of the USDA Plant Hardiness Zone Map have been printed.
But state, regional, and national images of the map can be downloaded
and printed in a variety of sizes and resolutions."
And an article on the new map in the Washington Post -
http://www.washingtonpost.com/local/plant-hardiness-map-revealed/2012/01/25/gIQANAxtQQ_story.html?hpid=z4:
""The new map is generally one 5-degree Fahrenheit half zone warmer
than the previous map throughout much of the United States," said Kim
Kaplan, of the Agricultural Research Service.
"She said that in spite of the zone creep, the new map is not meant to
validate climate change, and that the changes are driven in part by
more sophisticated and fuller data collection. Using new technology,
the map makers have been able to assess the effects of elevation,
prevailing winds, bodies of water and urban heat islands in a way the
old map could not, she said. Viewers can now type in their ZIP codes
to get zone information."