The U.S. Department of Agriculture told us in 2006 that we were now in zone 4A where the lowest winter temperature was -30 degrees. We had been in zone 3A
USDA changed hardiness zone map What it means for Minnesota growers? startribune.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from startribune.com Daily Mail and Mail on Sunday newspapers.