Does anyone have the translation of the usda hardiness frost zone keys which
accompany american text on plants. I would be grateful if anyone could fill
me in on the key.

tim wrote:

Does anyone have the translation of the usda hardiness frost zone keys which
accompany american text on plants. I would be grateful if anyone could fill
me in on the key.

Do you mean the USDA hardiness zone system? Here you will find some
info:
http://markw.com/hzones.htm
http://www2.dicom.se/fuchsias/eurozoner.html
But -
This zone system just gives the average yearly recorded minimum
temperatures. It should be noted that for the winter survival of a
certain plant, in any given location, many other factors also play a
role (local humidity, local temperature fluctuations, amount of wind
and sunshine, latitude, microclimate etc.) A continental climate (the
US) is not the same as a maritime climate (the UK).
Regards
Roger.

--
Walk tall, walk straight, and look the world right into the eye.

You're welcome to visit my gardening page:
http://users.pandora.be/roger.van.loon/gardenp.htm

In article ,
tim wrote:
Does anyone have the translation of the usda hardiness frost zone keys which
accompany american text on plants. I would be grateful if anyone could fill
me in on the key.

Zone 8 is winter temperatures down to 15 degrees Fahrenheit, and they
go in 10 degree units. But they don't make a lot of sense in the UK.
You are better off assuming that the colder parts of the UK are zone 7,
and the warmer parts zone 8, rather than taking any notice of the
temperatures.

Even then, they don't match. The conditions are just too dissimilar.
And the USDA zones are a damn-fool idea anyway, as they measure an
extreme value rather than a central one, and that is NOT a reliable
indicator of what will affect plants. If they measured the average
minimum daily average, they would translate a LOT better.


Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QH, England.
Email:
Tel.: +44 1223 334761 Fax: +44 1223 334679

"tim" wrote in message
...
Does anyone have the translation of the usda hardiness frost zone keys
which
accompany american text on plants. I would be grateful if anyone could
fill
me in on the key.


Thankyou Roger and Nick, most helpful info.

"Nick Maclaren" wrote in .
And the USDA zones are a damn-fool idea anyway, as they measure an
extreme value rather than a central one, and that is NOT a
reliable//////////////Bottom line.......I find them very useful when
combining with other factors........far from being a "damned fool
idea"........I would not consider growing a plant listed as zone 8 min. when
I am in zone 6 (regardless of other factors)........I also admit the a plant
listed for zone 7 might not be in my grow list for other climatic reasons.

Harold Walker

In article IlX4a.169127$iG3.19825@sccrnsc02,
Anne Middleton/Harold Walker wrote:

"Nick Maclaren" wrote in .
And the USDA zones are a damn-fool idea anyway, as they measure an
extreme value rather than a central one, and that is NOT a
reliable//////////////Bottom line.......I find them very useful when
combining with other factors........far from being a "damned fool
idea"........I would not consider growing a plant listed as zone 8 min. when
I am in zone 6 (regardless of other factors)........I also admit the a plant
listed for zone 7 might not be in my grow list for other climatic reasons.

The reason that they are a damn-fool idea is that the average minimum
winter temperature is directly relevant ONLY to plants that rely on
their above-ground parts overwintering, and is marginal even for them.
Using the average minimum daily average would make it relevant (a) to
more of them and (b) to plants that overwinter underground.

In the USA (an almost wholly continental climate), the soil never
freezes in zone 8, let alone zone 9. In the UK (an almost wholly
maritime climate and MUCH further north), it does, readily. It has
been dropping to -4 to -5 Celcius here (borderline USDA zone 8/9)
and the ground has frozen hard, probably a couple of inches down.

In the contiguous USA, there is a STRONG correlation between the average
minimum winter temperature and the average minimum daily average, but
it does NOT extend outside that restricted ranage of climate types.
In the UK, there is a very poor correlation, and there is almost none
with the USA.


Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QH, England.
Email:
Tel.: +44 1223 334761 Fax: +44 1223 334679

"Nick Maclaren"
"Nick Maclaren" wrote in .
And the USDA zones are a damn-fool idea anyway, as they measure
///////////////// to repeat Nick, it is a useful tool but not the only one.

HW.

Anne Middleton/Harold Walker wrote:

"Nick Maclaren"
"Nick Maclaren" wrote in .
And the USDA zones are a damn-fool idea anyway, as they measure
///////////////// to repeat Nick, it is a useful tool but not the only one.

It is only useful in a continental climate. It gives insane results when
applied in the UK. The UK winter cold and the damp will kill lots of things
that USDA zones would have you believe were winter hardy.

The Sunset Climate Zones for the Pacific NW are a closer match but still not
perfect.

http://oregonstate.edu/dept/ldplants/sunsetzn.htm

Regards,
Martin Brown

In article ,
Roger Van Loon wrote:
I'm sure there are very many serious plant growers in the UK. And I'm
equally sure that, when they do look up a plant, and the info says
"Z8" or "Z9" or "Z10", that this is, for them, very useful info
(combined with other factors). It surely must be one of the factors
that let them decide wether or not they can try it outside in their
own specific location.
Surely you wouldn't try out Z10 plants in your backyard?

We do. Next question?

As a good rule, in the relevant ranges of USDA zones 7 to 9, there is
a VERY POOR association between the USDA zone categorisation and the
hardiness of the plants on the UK. In fact, a good proportion of
USDA zone 6 plants are too delicate for the UK :-(

If the average minimum temperatures (which means: amount of frost) do
not play any role whatsoever where you are, OK , then I'll shut up.

No, actually, it DOESN'T mean "amount of frost" in any reasonable
sense, and that is part of the point. It refers to the extreme low
in an average winter, which is NOT the same as what most gardeners
mean by amount of frost, especially not in the UK.

[ In this context, may I draw to your attention the connotations of
the terms "a short, sharp snap" and "a hard frost"? The former is
often colder than the latter, but the latter implies that more things
actually freeze. ]

Of the major factors affecting the hardiness of plants, it is one
that is relevant to only a small proportion of plants, whereas there
are others that affect far more. And a good proportion of those
other factors are both measurable and applicable across a far wider
range of climate types. Some of the most important to the UK are not
easily measurable, unfortunately.

As I have posted before, with evidence, and been flamed for so doing,
the traditional indicator is the latitude at which the species is
found growing naturally. This is a bad indicator, but is certainly
no worse than the USDA zones.

And, again, as I posted, if the measurement were the average minimum
daily average rather than the average extreme minimum, it would be
VASTLY more useful and VASTLY more widely applicable - as well as
being equally easily measurable. It is perfectly reasonable to say
that ignoring this fact is a damn-fool idea. It was and is.

The fact that the information can be used, with unreliability and by
an expert, does not make it a good thing for UK gardening purposes.


Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QH, England.
Email:
Tel.: +44 1223 334761 Fax: +44 1223 334679

On Thu, 20 Feb 2003 10:39:43 GMT, "Anne Middleton/Harold Walker"
wrote:


"Nick Maclaren"
"Nick Maclaren" wrote in .
And the USDA zones are a damn-fool idea anyway, as they measure
///////////////// to repeat Nick, it is a useful tool but not the only one.


I don't find it to be much use, according to the USDA Zones I'm in
zone 10/11 here in London, but there are very few plants from these
zones that are worth trying.
--
Pete The Gardener
A room without books is like a body without a soul.

On 19 Feb 2003 21:56:40 GMT, (Nick Maclaren)
wrote:

Even then, they don't match. The conditions are just too dissimilar.
And the USDA zones are a damn-fool idea anyway, as they measure an
extreme value rather than a central one, and that is NOT a reliable
indicator of what will affect plants. If they measured the average
minimum daily average, they would translate a LOT better.


Now, now, Nick, temper, temper. The USDA zones were devised with
a specific purpose in mind, hardiness of *woody* material in the
continental USA. The USDA has had some pretty bright people
toiling away in the bowels of its bureaucracy (at least in the
past), and I am quite sure that the hardiness zone system was not
just a bright but ill thought-out idea someone foisted onto the
world in a moment of carelessness.

That the system has been widely misapplied to other types of
plant material and in other places is not an inherent fault.


--
Rodger Whitlock
Victoria, British Columbia, Canada

I live in the center of the US and am in zone 5. What that means to me is
that I can plant anything that wont die if exposed to colder than -20
degrees F ( I don't know what that translates to in Celsius , but if I am
correct, 0 C = 32 F, and 30 C = around 80F).

Looking at the zone map, parts of California, Arizona, and the southern
states are zones 9 and 10. Although they might get an infrequent killing
frost, I doubt that the ground would ever freeze. They can grow oranges,
avocados and palm trees, without having to worry too much about the cold
weather.

Hope this helps. Good luck. Dwayne

"tim" wrote in message
...

"tim" wrote in message
...
Does anyone have the translation of the usda hardiness frost zone keys
which
accompany american text on plants. I would be grateful if anyone could
fill
me in on the key.


Thankyou Roger and Nick, most helpful info.

..
| And the USDA zones are a damn-fool idea |
| Now, now, Nick, temper, temper. The USDA zones were devised with
| a specific purpose in mind, hardiness of *woody*

That is true, and I wish people would stop doing it./////////////
Nick, is that an all inclusive statement.....meaning that we in the USA
should stop using this valuable tool?????????

Some of my most valuable gardening books are of English origin but I would
never suggest chucking 'em out because they contain material of no value to
the parts of the USA where it is colder than hell in the winter time and
gardening, as you know it over there, does not exist......such utter
nonsense and tripe as planting broad beans in the autumn months to give a
head start for the following year or planting spring cabbage seedlings in
the autumn months..........perhaps I should reconsider and consign those
books to the scrap heap or the compost heap??????
HW.

In article ,
"Anne Middleton/Harold Walker" writes:
|
| .
| | And the USDA zones are a damn-fool idea |
| | Now, now, Nick, temper, temper. The USDA zones were devised with
| | a specific purpose in mind, hardiness of *woody*
|
| That is true, and I wish people would stop doing it./////////////
| Nick, is that an all inclusive statement.....meaning that we in the USA
| should stop using this valuable tool?????????

I should appreciate not being misquoted. Please do not repeat it.
To remind you, here is the context that you removed:

| That the system has been widely misapplied to other types of
| plant material and in other places is not an inherent fault.

That is true, and I wish people would stop doing it.


Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QH, England.
Email:
Tel.: +44 1223 334761 Fax: +44 1223 334679

On 21 Feb 2003 08:40:36 GMT, (Nick Maclaren)
wrote:


Rodger Whitlock writes:

...The USDA zones were devised with
a specific purpose in mind, hardiness of *woody* material in the
continental USA.

Perhaps I am too stringent, but I regard anyone who invents such
a scheme without thinking of its potential for extension as being
a fool...at the very least they should have considered
its relevance to herbaceous crop plants.

Not really (imo). The only important herbaceous crop that
over-winters, and for which hardiness is therefore an issue, is
fall-sown wheat, afaik. The other big grain crop grown in the US
is corn (maize), which is invariably sown in the spring.

And it may be that the deviser realized that a system suitable
for herbaceous material was impractical as their hardiness
depends on many other factors than just temperature, whereas the
hardiness of woody material (sc. fruit trees) is really dependent
only on the winter low temperature.

Horticultural material doesn't have enough economic importance to
count in this kind of study.

--
Rodger Whitlock
Victoria, British Columbia, Canada