About Plant Hardiness Zones

Plant hardiness zones are a general guide to help you know which plants will grow where you live because plants vary in the temperature extremes they can endure.

Years ago botanists and horticulturists started gathering weather records throughout the United States to build a database to show the average coldest temperatures for each region of the U.S.  These records were consolidated into a range of temperatures and converted into various zones of plant hardiness.  Maps were then made to show the delineations between these temperature zones.

The USDA map, which was last updated and released in 2012 (based on weather records from 1976-2005), is the standard measure of plant hardiness throughout the United States.

Please be aware that Plant Hardiness Zones are only a general guide.  Many other factors influence whether a plant will survive in your garden or not.  You must also consider:   Soil types, rainfall, daytime temperatures, day length, wind, humidity and heat.  Within your own yard, block and county, there are microclimates that affect how plants grow.  One part of your yard may be hotter, colder, wetter, dryer, shadier or sunnier than another and certain plants may do better in one spot than another because of this.  The zones are a good beginning, but you still need to determine for yourself what will and won’t work in your garden.

2012 USDA Plant Hardiness Zone Map for Florida.