USDA zones in Australia
Samantha Lane
I think I've figured out USDA zone equivalents for Aust. Capital
cities. It turns out that most of us live in zone 10.
This is how I figured it out - I couldn't find ave. yearly min data
but I could find mean and 14 percentiles for the minimum temp. for
each month. I figured the 3.3 percentile for July would be a good
approx. to ave. yealy min as this is the value the T is likely to
go below once in that month. I took the 14 percentile to be 1 std.
dev. from the mean and 3.3 to be 1.8 std devs from the mean so the
3.3 percentile is at mean - 1.8 * (mean - 14 percentile). Does anyone
want to comment on my maths? These are my results
city min T (C) zone
Adelaide 1.4 10
Brisbane 3.7 10
Canberra -8.1 8
Darwin 14.4 12
Hobart -0.5 10
Melb -0.3 10
Perth 1.9 10
Sydney 3.9 10
The zones are defined by ave yearly min
aone T(F) T(C)
12 50-60 10 - 15.5
11 40-50 4.4 - 10
10 30-40 -1.1 - 4.4
9 20-30 -7.7 - -1.1
8 10-20 --12.2 - -7.7
Hope people find this useful
Samantha Lane
Margaret Van Emmerik
s...@anpnt22.anp.ansto.gov.au (Samantha Lane) wrote:
>Hi,
> I think I've figured out USDA zone equivalents for Aust. Capital
>
>cities. This info. is handy if you're perusing rec.gardens or an
>american seed catalogue. Thompson and Morgan give hardiness in USDA
>zones I think. Anyway, it turns out that most of us live in zone 10.
The minimum temperature supplied above for Brisbane is very close to the
all time record minimum! The average minimum runs at much higher, probably
around 10 degress Celsius, although I do not have specifics.
I found some literature that relates to zones in Australia. I will quote
what they have to say:
Zone 1 - (Tropical): High temperatures all year round; heavy summer rains;
frosts do not occur; average annual lowest temperature 15 degress Celsius.
Zone 2 - (Subtropical): Mild, dry winter and reliable summer rainfall;
high humidity from November to March; frosts are rare; average annual
lowest temperature 10 degrees Celsius.
Zone 3 - (Warm temperate): Mild winters with light frost, except on the
coast; reliable year round rainfall; average annual lowest temperatures 5
degrees Celsius.
Zone 4 - (Mediterranean): Warm wet winters and sunny, hot summers with low
rainfall; hot inland winds; the average lowest temperature is 5 degrees
Celsius.
Zone 5 - (Cool temperate): Low winter temperatures with frosts during the
cooler monthes; warm summmers; average annual lowest temperatures 0 degrees
Celsius.
Zone 6 - (Cool): Mountainous or highland areas with mild temperatures and
cool nights; heavy frosts and some snow in winter; average annual lowest
temperature -5 degrees Celsius.
Zone 7 - (Inland): Very high summer temperatures; cold nights and
prolonged droughts; the average annual lowest temperatures is -5 degrees
Celsius.
Quoted directly from in the inside cover of Gardening Made Easy - Step by
Step to a Beautiful Garden.
I have read elsewhere where Australian was divided into as few as four
zones. I personally like the above break down better.
Going by that and the map supplied, then the Australian capital cities
would fall into the following zones:
Canberra - zone 6 - cool
Brisbane - zone 2 - subtropical
Sydney - zone 3 - warm temperate
Melbourne - zone 4 - mediterranean
Hobart - zone 5 - cool temperate
Adelaide - zone 4 - mediterranean
Perth - zone 4 - mediterranean
Darwin - zone 1 - tropical
Other cities:
Alice Springs - zone 7 - inland
Cairns, Townsville - zone 1 - tropical
(NZ) Wellington, Auckland and Christchurch - zone 6 - cool.
My opinion is that we cannot compare with UZ zones effectively so why try?
So long as we understand what they mean by their zone references we can
then cross reference to our own.
Regards, Margaret Van Emmerik, Brisbane.
Come see my web page at http://www.gil.com.au/~emmerik although be
warned - it is still under construction!
Donald R Smith
We seem to be getting worse here.
I see you live in Brisbane. Have you ever lived in Perth? - or
Melbourne?
I've just found some more information that gives Melbourne's
average rainfall as 26" whilst Perth is 36". That's quite a
difference for locations supposedly in the same zone. Further,
Perth gets most of its rain in those few months popularly called
winter. Very little rain in the summer. Melbourne on the other
hand (according to my references) gets around the 2" mark each
month, summer or winter. Any publication which suggests these two
cities are in the same climatic zone is suspect.
I will seek some definitions from the met bureau and the CSIRO (
if that's still their name.) We need a scientific reference rather
than a rough diagram in some magazine.
When it's all boiled down, in spite of what the pundits say (who
all live in Melbourne anyway ) if the plant grows in your local
area - goodoh, but don't always believe the book.
Don Burke's advice. Walk around the neighbourhood and see what
other people have in their gardens. It never fails.
Don
--
Donald R Smith drs...@witsend.dialix.oz.au
tel (09) 390 9933 http://www.dialix.oz.au/~drsmith/drsmith.htm
Kelmscott 6111
Western Australia
Donald R Smith
In article <4hobhg$m...@misery.millcomm.com>, Stephen D Spratley (spra...@millcomm.com) writes:
>In article <4...@witsend.DIALix.oz.au>, drs...@witsend.DIALix.oz.au says...
>>
>>
>>In article <AD5F34E4...@cs7p1.ipswich.gil.com.au>, Margaret Van Emmerik
>>(emm...@gil.com.au) writes:
>>>In article <4gvubl$c...@atom.ansto.gov.au>,
>>>s...@anpnt22.anp.ansto.gov.au (Samantha Lane) wrote:
>>>
>>>>Hi,
>>>> I think I've figured out USDA zone equivalents for Aust. Capital
>>>>
>>>>cities. This info. is handy if you're perusing rec.gardens or an
>>>>american seed catalogue. Thompson and Morgan give hardiness in USDA
>>>>zones I think. Anyway, it turns out that most of us live in zone 10.
>
>
>
>I think you have missed the point of the USDA zoning, and agricultural zoning
>in general, as pointed out in Margaret's article, which is inclined towards
>lowest prevalent temperatures. Excessive rainfall can be countered by choosing
>an appropriate soil for the particular plant and planting situation. For
>instance, a willow tree might do well in a poorly drained clay, but not in a
>well drained sand, irrespective of the rainfall. However, if a plant is not
>tolerant of cold temperatures, it won't survive in any soil. Here in Minnesota
>we can easily get to -20F (-29C). This makes the USDA zones of EXTREME
>importance for the choice of plants! By the way, having lived in South Africa
>most of my life, I do know about warmer climes, too! ;o)
>
>Regards,
>
>
>----------------------------------------------------------------------------
>Stephen D. Spratley | The race is not always to the swift,
>spra...@millcomm.com | nor the battle to the strong.
>============================================================================
>
>
Stephen,
Margaret's points about the USDA zones amy be correct for USA and
may correspond to certain areas in Australia.
My point solely is that any set of figures or definitions which
purport to give Melbourne and Perth the same climate is ridiculous!
I have supported my statements with references and had hoped that
others might find other evidence of the differences of these two
cities.
Now I don't give a hoot about the climatic zones in USA and am
surprised that anyone in USA would tell me they know intimately the
climate in any of Australian cities.
I have had a reply from Margaret in which she mentioned that she
was unaware that she had made the point of comparison between the
two. Nevertheless, her figures did that for her.
Now, if anyone can point me to a reputable and preferabley
scientific source which will support the notion that these two
AUSTRALIAN cities share the same climate, I will be glad to
acquiesce.
Thankyou for your interest Stephen but I think we can manage this
local problem of definition within our own resources.
Rick Cook
>
>A regional garden reference called Sunset has a much more useful set of
>zones for the western US, which take into account winter temps, summer temps,
>rainfall (or lack of it), and the like.
The Sunset zones are much more useful. However they are only available AFIK
for the West and even so there are more than 20 of them. Further, most
everyone expresses hardiness in terms of USDA zones, which at least gives
you a fighting chance.
--RC (Sunset Zone 13, USDA Zone 9 or 10)
Samantha Lane
> Re: USDA zones in Australia
>
> drs...@witsend.DIALix.oz.au (Donald R Smith)
> Sat, 09 Mar 1996 00:02:45 GMT
>
> Margaret's points about the USDA zones amy be correct for USA and
> may correspond to certain areas in Australia.
> My point solely is that any set of figures or definitions which
> purport to give Melbourne and Perth the same climate is ridiculous!
But in the commonly used system of cold - temperate - tropical they
are considered the same! And it is ridiculous. What shall we do about
it?
> Now, if anyone can point me to a reputable and preferabley
> scientific source which will support the notion that these two
> AUSTRALIAN cities share the same climate, I will be glad to
> acquiesce.
Under the definition of the USDA zone system they are the same climate.
The zones I posted were simply meant as a guide for people using
american resources such as rec.gardens. They simply show that Australia
is hot, which we knew, and that having capitol cities near the sea
makes theam temperate, which we also knew.
Samantha Lane Australian Nuclear Science and
s...@anpnt22.anp.ansto.gov.au Technology Organistation
ISD + 61 2 717 3601 New Illawarra Rd ,
Lucas Heights. 2234
Karen O'Shea
>Under the definition of the USDA zone system they are the same climate.
>The zones I posted were simply meant as a guide for people using
>american resources such as rec.gardens. They simply show that Australia
>is hot, which we knew, and that having capitol cities near the sea
>makes theam temperate, which we also knew.
Kia ora,
And this would be fine if the whole world was the USDA but it isn't.
It means for those of us non USDA dwellers who would like to
contribute in a meaningful (or as I have been known to do
meaningless) manner that these zones are less than useless. So to
say we knew Australia is hot is fine and dandy unless you
are gardening in an area of Australia where it snows and are
asking a query of somenoe who insists that all Australia is zone 9
or somesuch.
p.s New Zealand is not Australia.
-Ka Fish-
My aim in life is to find something I do not have an opinion about
and become an expert on it.
(that is if I ever get off jury service)
Karen O'Shea
>
>Zones in Austrialia would be upside down, wouldn't they. Ours run
>from top to bottom with the small numbers being at the top. In
>Austrialia it seems like the small numbers would be at the bottom and
>get larger as you went to the top.
Kia ora,
And I just thought it was because all the pages were printed upside
down!