Well let us begin by explaining the USDA Plant Hardiness Zone map. You will have to understand the map before you will know if a plant is tropical or not. The USDA has put together a map that breaks up North America into 11 different temperature zones. Minneapolis, Minnesota is zone four, while Miami, Florida is zone 10. We will go into to further detail on this map at a later date.
The importance of knowing this map, is each plant has a certain cold temperature that it can withstand. When purchasing a plant, you must understand its cold hardiness. If a plant can withstand minimum temperatures of 40 degrees Fahrenheit, than it is not a good idea to plant them outside in Tennessee. Most plant tags will have the ‘zone hardiness’ for the plant. It is usually a range…like zone 6-9, or 4-7. Again, this means that this plant will withstand cold temperatures down to the lowest zone. It can also be affected by the high temperature. Florida is too hot for some plants to grow. Many deciduous plants (the ones that drop their leaves) will not survive in Florida because they do not have a ‘cold’ period for the plant to go dormant. On the other hand, palm trees will not survive in Tennessee because we have a ‘cold’ period. Make sense?
So what do you do with a tropical plant if you live anywhere north of Florida? Plan a spot on the inside of the house to store it all winter long! Make sure you learn what zone you are in, and plan your landscape accordingly. I live in Nashville, Tn and we can grow tropical plants all summer with great success, but come October, they will kick the bucket. Knowing this is very important to the pocket book and the ultimate look of the landscape. Here is a short list of the different Cold Hardiness Zones
USDA Hardiness Zones and Average Annual Minimum Temperature Range
|
Zone |
Fahrenheit |
Celsius |
Example Cities |
|
1 |
Below -50 F |
Below -45.6 C |
Fairbanks , Alaska; Resolute, Northwest Territories (Canada) |
|
2a |
-50 to -45 F |
-42.8 to -45.5 C |
Prudhoe Bay , Alaska; Flin Flon, Manitoba (Canada) |
|
2b |
-45 to -40 F |
-40.0 to -42.7 C |
Unalakleet , Alaska; Pinecreek, Minnesota |
|
3a |
-40 to -35 F |
-37.3 to -39.9 C |
International Falls , Minnesota; St. Michael, Alaska |
|
3b |
-35 to -30 F |
-34.5 to -37.2 C |
Tomahawk, Wisconsin; Sidney, Montana |
|
4a |
-30 to -25 F |
-31.7 to -34.4 C |
Minneapolis/St.Paul, Minnesota; Lewistown, Montana |
|
4b |
-25 to -20 F |
-28.9 to -31.6 C |
Northwood , Iowa; Nebraska |
|
5a |
-20 to -15 F |
-26.2 to -28.8 C |
Des Moines , Iowa; Illinois |
|
5b |
-15 to -10 F |
-23.4 to -26.1 C |
Columbia , Missouri; Mansfield, Pennsylvania |
|
6a |
-10 to -5 F |
-20.6 to -23.3 C |
St. Louis , Missouri; Lebanon, Pennsylvania |
|
6b |
-5 to 0 F |
-17.8 to -20.5 C |
McMinnville , Tennessee; Branson, Missouri |
|
7a |
0 to 5 F |
-15.0 to -17.7 C |
Oklahoma City , Oklahoma; South Boston, Virginia |
|
7b |
5 to 10 F |
-12.3 to -14.9 C |
Little Rock , Arkansas; Griffin, Georgia |
|
8a |
10 to 15 F |
-9.5 to -12.2 C |
Tifton , Georgia; Dallas, Texas |
|
8b |
15 to 20 F |
-6.7 to -9.4 C |
Austin , Texas; Gainesville, Florida |
|
9a |
20 to 25 F |
-3.9 to -6.6 C |
Houston , Texas; St. Augustine, Florida |
|
9b |
25 to 30 F |
-1.2 to -3.8 C |
Brownsville , Texas; Fort Pierce, Florida |
|
10a |
30 to 35 F |
1.6 to -1.1 C |
Naples , Florida; Victorville, California |
|
10b |
35 to 40 F |
4.4 to 1.7 C |
Miami , Florida; Coral Gables, Florida |
|
11 |
above 40 F |
above 4.5 C |
Honolulu , Hawaii; Mazatlan, Mexico |
So What is a Tropical Plant? A Tropical Plant is any plant that will not survive your cold hardiness zone. Each plant is different for each zone in the country.
Happy Tropicals