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Read More July 7, 2016 | Blain's Farm & FleetUSDA Hardiness Zones and Gardening
Find out which USDA hardiness zone you’re in before starting a garden.
USDA hardiness zones help you know which plants grow best in different parts of the country. This is an important thing to know when considering starting a garden.
Have you ever thought about which plants will flourish in your region? While you may have a plan for where you want your plants and what you think looks best, it’s important to consider the specific needs of your chosen flora.
Blain’s Farm & Fleet is here to provide you with the necessary information you need to determine what fruits, vegetables, flowers, and more will thrive in your yard!
The United States is a huge country, spanning from the Atlantic to the Pacific. From its dry deserts filled with cacti, to areas of grassy plains, to subarctic and tropical regions, the plants you’ll find vary greatly as you go about from region to region.
Why Are The USDA Hardiness Zones Important?
USDA plant hardiness zones show the average of extreme minimum temperatures for an area, calculated from the lowest daily minimum temperature recorded. This does not represent the coldest it has ever been or ever will be in an area. It simply is the average of lowest winter temperatures for a given location for this time period.
This is important to consider when choosing the best plants for your area because some plants survive better in colder temperatures than others.
This is also important to know for both rural and urban planters, as each of these areas have many factors that can affect the temperature.
Cities hold more heat because there is more blacktop and concrete, so a city may have a higher zone than the surrounding rural areas. Areas with higher elevation tend to be colder than surrounding low laying areas, so they may have a cooler zone. Locations near a large body of unfrozen water may have milder winter weather and will be considered to be in a warmer zone.
This means that someone living in a city probably won’t be planting many of the same fruits and vegetables in their garden bed, for example, than someone living near the mountains would be in their home garden.
USDA Hardiness Zones
USDA hardiness zones range from 1 (coldest) to 13 (warmest). Each zone has a 10 degree difference between them. The zones also have two sections, “a” and “b,” which have a five degree difference between them.
Here is a list of all of the zones as named by the USDA, with their temperature ranges and a few examples of cities that reside in these zones.
| USDA Zones | Temperature Ranges | Example Cities |
|---|---|---|
| Zone 1a | -60° F to -55° F | Fort Yukon, Alaska |
| Zone 1b | -55° F to -50° F | Alaska North Slope |
| Zone 2a | -50° F to -45° F | Fairbanks, Alaska |
| Zone 2b | -45° F to -40° F | Buckland, Alaska |
| Zone 3a | -40° F to -37.2° F | Denali, Alaska |
| Zone 3b | -35° F to -30° F | International Falls, Minnesota |
| Zone 4a | -30° F to -25° F | Hayward, Wisconsin |
| Zone 4b | -25° F to -20° F | Eau Claire, Wisconsin |
| Zone 5a | -20° F to -15° F | Fort Dodge, Iowa |
| Zone 5b | -15° F to -10° F | Madison, Wisconsin |
| Zone 6a | -10° F to -5° F | Lansing, Michigan |
| Zone 6b | -5° F to 0° F | Buffalo, New York |
| Zone 7a | 0° F to 5° F | Harrisburg, Pennsylvania |
| Zone 7b | 5° F to 10° F | Nashville, Tennessee |
| Zone 8a | 10° F to 15° F | Atlanta, Georgia |
| Zone 8b | 15° F to 20° F | Dallas, Texas |
| Zone 9a | 20° F to 25° F | San Antonio, Texas |
| Zone 9b | 25° F to 30° F | Sacramento, California |
| Zone 10a | 30° F to 35° F | Orlando, Florida |
| Zone 10b | 35°F to 40° F | Los Angeles, California |
| Zone 11a | 40° F to 45° F | Miami, Florida |
| Zone 11b | 45° F to 50° F | Florida Keys, Florida |
| Zone 12a | 50° F to 55° F | Wahiawa, Hawaii |
| Zone 12b | 55° F to 60° F | Honolulu, Hawaii |
| Zone 13a | 60° F to 65° F | San Juan, Puerto Rico |
| Zone 13b | 65° F to 70° F | Isla Verde, Puerto Rico |
Thing to Consider Before Planting
Remember that the USDA hardiness zones are simply a tool to help gardeners choose the best plants for their area. This is by no means an absolute, and many plants can grow in different zones.
Make sure you are doing your research before you buy plants and vegetable seeds for your garden. Blain’s Farm & Fleet can aid in your research by providing more gardening tips and information in our Gardening Blog.
