|
Converting
Fahrenheit into Celcius or the opposite
What
are hardiness zones?
It seems every gardening
book and nursery catalog refers to plant
hardiness zones, also known as climate zones or growing zones. If
you`re new to gardening,
you may be wondering what all the fuss is with these zones, and how to
find out which zone you are gardening in.
Basically,
plant hardiness zones are a guide to help you know which plants will
grow where you live, so you don't plant things that will soon die just
because they can't manage your region's temperatures.
Plants vary in the temperature extremes they can endure. Basic
laboratory testing can determine the lowest sustained temperature a
particular plant type can withstand, but, as gardeners, we still need
to know how these measurements relate to our own gardens.
Hardiness Zones
-- Details
Zones 2-10 in the map have been
subdivided into light- and dark-colored sections (a and b) that
represent 5 F (2.8 C) differences within the 10 F (5.6 C) zone. The
light color of each zone represents the colder section; the dark color,
the warmer section. Zone 11 represents any area where the average
annual minimum temperature is above 40 F (4.4 C)
The
map shows 20 latitude and longitude lines. Areas above an arbitrary
elevation are traditionally considered unsuitable for plant cropping
and do not bear appropriate zone designations. There are also island
zones that, because of elevation differences, are warmer or cooler than
the surrounding areas and are given a different zone designation.
Note that many large urban areas carry a warmer zone designation than
the surrounding countryside. The map-contains as much detail as
possible, considering the vast amount of data on which it is based and
its size.
| Hardiness
zones and average annual minimum temperature range |
|
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 |
|
|
|
