Zones for Gardening In November of 2023, for the first time in a decade, the U.S. Department of Agriculture made a change to the “Plant Hardiness Zone” map.

"Zone 4 is a big geographic area and so when we look at something, if it says zone 4, investigate a little more. Many of those things might be winter hardy," Kinzler said.

The USDA divides the United States into seven planting regions, known as hardiness zones, which were most recently updated in 2023. The maps below show these planting regions.

For example, the coldest hardiness zone in the lower 48 states on the new map, 3a, covers small pockets in the northernmost parts of Minnesota and has winter extreme temperatures of -40 F to -35 F.

Minnesota farmers made good progress planting between rain showers during the week ending April 24, according to USDA’s National Agricultural Statistics Service. Minnesota’s corn planting ...

Hardiness zones represent the average annual extreme minimum temperature during a 30-year period. In zone 5a, the lowest temperature on average was between minus 15 and minus 20 degrees Fahrenheit.