Margaret Roach at the "Away to Garden" blog reports on the new USDA Hardiness Map, and half of the nation's 80 million gardeners are now a half-zone warmer in the first update since 1990. “The increase in our computing power today allows the research team to build into their algorithms things they knew were important factors in 1990, but couldn’t include,” said Catherine Woteki, Chief Scientist and Under Secretary for Research, Education and Economics for the USDA, in an interview yesterday. Factors such as elevation, the slope of land, or how close to a body of water a location is, can cause sharp variation despite close adjacencies. “Taking those into account now provides a lot more detail,” Woteki said, “and people will be able to see islands of heat, and also cool ones, on the new map. As a scientist and a home gardener, I love seeing this so much more clearly.” Read the full story at Away to Garden.