Plant Hardiness Map

April 09, 2002

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Provided by: USDA/ National Arboretum
Summary authors & editors: Jim Foster

In only a few places in the US is winter still holding on with a strong grip. However, with daylight savings in effect now, we'll be able to take advantage of the increased evening daylight to pursue outside hobbies and activities. If you're a gardener, the USDA uses a plant hardiness map (above) that should give you an idea of the kinds of plants that you'll be able to grow in your garden. It's based on the annual minimum temperature for a particular location, and has 11 major zones. A new map will be released later this year and will reflect the shift in boundaries from the first such map that was produced in 1965. The shift is due to the generally warmer winter temperatures across the country during the last 20 years. The map above is a 1990 version of the original 1965 map.

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