USDA Arizona Hardiness Zones: 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b
Many people think of Arizona as dry and desert, which wouldn’t be wrong. A large portion of Arizona is an arid desert. But Arizona has a wide range of hardiness zones throughout the state, making it a challenge to know which one you actually live in.
Imagine dry deserts with extreme temperature fluctuations, cold mountains, and a range of arid, semi-arid, and even humid conditions. Overall, Arizona receives less precipitation than average in the United States and has more sunny days.
While a large portion of the state consists of hot, dry, low elevation desert, at least half the state resides at over 4000 feet above sea level, making Arizona an incredibly diverse climate area.
Arizona Planting Zone – A Quick Overview:
- If you live in the mountains of Arizona, such as near Flagstaff, you might find yourself in the coldest growing zones of 5a or 5b. Flagstaff itself is classified as 6a.
- On the other hand, if you live in the southwest region of the state, or the desert areas, you’ll be in the warmer zones such as 9b, 10a, or 10b.
- Phoenix and Tuscon are both classfied as zone 9b. Yuma is in zone 10a.
- The more northeastern portions of Arizona range from 6a through 7b.
- The average amount of annual rainfall in Arizona is 12 inches, compared to the US average of 38 inches.
- Arizona only receives about 6 inches of snow each year.
- While most of the United States receives about 200 days of sunshine each year, Arizona receives about 300 days of sunshine.
- Summers can easily reach 100 degrees, while winter lows only get about 34 degrees.
- Higher elevations will be cooler in the winter, while the low desert can be extremely hot.
Using the Arizona Growing Zones Map
Since Arizona has such a varied climate, the easiest way to understand what will grow in your area is to use the hardiness map for Arizona. This is based on the 2012 USDA map data. Hardiness zones were created to help gardeners and farmers understand how to grow the best gardens in their area by taking climate and weather into consideration.
The easiest way to find your Arizona gardening zone is to search by your zip code. You could also just look on the map for where you live. The map will have a range of colors that coordinate with the Arizona climate zones. You can match the color of the map where you live to the key for each specific Arizona gardening zone.
It’s important to understand that the USDA map is a general guide. Specific areas may be slightly warmer or cooler than the grow zone states due to the differences in terrain. Differences in elevation, living near forests, urban areas, or open areas can all affect the specific growing zone you live in.
Because Arizona is such a dry state, you may want to create your own microclimates to enhance your gardening. For example, you can use vegetation, such as hedgerows, or boulders, to block heavy winds. You can also use them to direct water towards or away from your garden. You may even be able to extend your growing season a bit by placing your plants in more sheltered areas.
You can talk to local farmers and gardening experts to learn more about your specific microclimate.
Arizona: A State of Extremes
The challenge of gardening in Arizona is the wide temperature fluctuations and lack of moisture in desert areas. But if you plan well, you can still have a successful garden, even in the lower desert areas. For example, you may want to look for a spot that receives early morning sunshine but not intense afternoon sun. Or you may need to use a shade cloth to protect sensitive or cool weather plants in the afternoon.
Vegetables that thrive in the heat do well in the Arizona sun, so you might consider planting vegetables such as eggplant, peppers, corn, and potatoes. In addition, you can grow citrus trees in the low desert, and in the northeastern areas of Arizona, you can even grow apples, peaches, and plum trees.
If you are growing fruit trees, Primex Garden Center recommends using a tree gator to provide a slow and steady drip of water for your fruit trees in the desert areas.