What is USDA zone 9b?
The USDA plant hardiness map zones were developed by the United States Department of Agriculture (USDA) to provide an easy guideline for categorizing locations suitable for winter survival of a rated plant in an “average” winter. As a very basic rule of thumb, if a plant is hardy in your zone, you can plant it.
The 1990-issue map was based on nearly double the number of stations, and it divided the temperature zones into five-degree a/b zones for greater accuracy.
In 2012 the USDA updated their plant hardiness map to reflect the warmer observed temperatures in the past thirty years.
The U.S. Department of Agriculture hardiness zones 9b include the warmer areas of the United States and temperatures are actually warm enough for year round gardening, planting and growth.
But still, in zone 9b some plants needs to be protected from cold where USDA Zone 9b lowest temperatures average 25 to 30 degrees Fahrenheit.
How many zones are there?
The USDA plant hardiness map divides North America into 11 hardiness zones. Zone 1 is the coldest; zone 11 is the warmest, a tropical area found only in Hawaii and southernmost Florida (and maybe the very southwest corner of San Diego County, California).
Keep in mind though, there are other factors that affect plant survival not considered in hardiness zones. For example, soil moisture, humidity, the number of days of frost, and the risk of a rare catastrophic cold snap, etc also play their roles in figuring out whether a plant will survive in your garden.
With that being said, obviously there can be many different kinds of climates that are USDA zone 9b. Take for example, Conditions in Florida zone 9b are different than coastal California zone 9b.
Here in Florida, the line between zones 9B and 10 runs through Martin, Palm Beach, Glades, Hendry, Lee, and Charlotte counties.
In this section of the Florida USDA zone 9b plants can suffer due to the challenges of sandy soil, heat and humidity, etc.. Yet the added benefit of summer rainfall helps temper the heat and reduces the amount of water your garden and landscape might otherwise require.
The USDA zones are a good starting point, but you still need to determine for yourself what will and won’t work in your garden. Observation is key to good gardening.
www.Zone9b.com is targeted to the Floridian USDA zone 9b gardeners… the lucky few who live in South Florida’s “sub-tropical paradise”, dealing with unique set of planting conditions that must be understood and taken into consideration.
Do you live or wished you lived in FL zone 9b?
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