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From:
To: Orchid Talk List
Subject: Reuters.com − Dutch flower growers aim to keep pace with the times − Sun Apr 22, 2007 9:42 PM ET
Date: Mon, 23 Apr 2007 11:55

Gordon Walker (giwalker@btopenworld.com) has sent you this article.
Personal Message:
Would this work for orchids? Gordon.

AMSTERDAM (Reuters) − Jaap Leenen, a 60-year old flower grower and the
biggest daffodil breeder in the Netherlands, says seashells from the
North Sea are the best thing that has ever happened to his daffodils.

Next to a yellow sea of swaying flowers, a mountain of tiny seashells
stands on his farm in Sassenheim, a village in traditional bulb-growing
territory half an hour's drive from Amsterdam.

Leenen started growing daffodils in trays of seashells only two years
ago to increase production to meet growing demand.

Pinkish white and the size of a child's fingers, the shells are
thoroughly washed before they are strewn onto the 2 meter (6 ft 6 in)
square trays in a 5 cm (2 inch) thick layer as a base to anchor the
flower bulbs.

Unlike soil, this helps keep bacteria, fungi and worms at bay, producing
cleaner bulbs for pharmaceutical use and longer-lasting blooms, said
Leenen.

The seashells also makes it easier to control the temperature, water
level and amount of nutrients fed to the plants, extending the planting
and harvesting season.

"We can produce flowers the whole year round through this way and not
just in spring. The flowers are better and have a longer vase life. The
plants are 100 percent free from all kinds of diseases and bacteria,"
Leenen said.

"The roots and the bulbs are very clean, the clean bulbs are necessary
to prepare galantamine," he said, referring to the substance found in
daffodils used to treat Alzheimer's disease.

Dutch flower growers are testing new ways to produce more and better
quality flowers and to exploit every part of the plant as they compete
against cheaper rivals seeking a slice of a highly lucrative industry.

The Dutch flower industry has roots stretching back centuries,
highlighted by the speculative 'Tulip mania' trading bubble in the first
part of the 17th century.

The Netherlands earned 17 billion euros ($23 billion) in 2005 from
horticultural exports which includes the production of ornamentals and
edible crops, according to the state statistics agency. Cut flowers
accounted for about a quarter of the total.

But Dutch growers have seen their share of the global flower and plant
trade fall below an estimated 60 percent in 2000, said Peter van der
Salm, market analyst at the Product Board for Horticulture representing
growers, auctioneers and traders.

New entrants like Chile, Colombia, Ecuador, Costa Rica, Mexico, Thailand
and New Zealand are already making inroads in key markets in Europe and
the United States, he said.

"It is probably a matter of price. For example, small roses are very
often now produced in Africa and transported to the United States and
Europe. Labor is very cheap in these countries," he said.

Latin American growers also have an edge over their European
counterparts in the winter in the northern hemisphere when demand peaks
around the festive holidays.

"Their bulbs come to the market in the late winter or spring in the
northern hemisphere and are at that moment fresher compared to the Dutch
bulbs. Most Dutch bulbs are harvested in the autumn," said van der Salm.

He said anecdotal evidence showed Dutch growers who have migrated to
South America and Africa and set up their own businesses were proving to
be formidable competitors too.

The strong euro versus the dollar has also dented Dutch flower exports,
making bulbs and flowers grown in Europe more expensive for U.S. buyers.

Flowers are more than just pretty blooms in a vase, said Jos Zuidgeest,
chief executive of Holland Biodiversity, which aims to interest
pharmaceutical and cosmetic companies in exploring extracts found in
flower bulbs.

Set up in 2003 by Dutch entrepreneurs and scientists, the company has
created a library of 320 plant extracts from the bulbs of the amaryllis,
iris and lily flower families.

Zuidgeest said he recently met with executives from the Singapore-based
consumer product unit of pharmaceutical firm Johnson & Johnson.

"They are interested," he said, adding that French cosmetics maker
L'Oreal has used some extracts from the library.

By teaming up with growers and ensuring that plants are grown under
strict and monitored conditions, Holland Biodiversity is able to provide
a large quantity of plants with the desired concentration of substances
to clients.

"We have found one bulb that we sell to a Japanese company in powder
form. The company had asked us to look out for it. It makes tablets and
sells them as a supplement food," he said.

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From: Ron Bower
To: Orchid Talk List
Subject: Emailing: Ron%20Bower%20Orchids%2031.3.07%20066.jpg
Date: Mon, 23 Apr 2007 15:10

Hello All,
Further to my war with the Mealy Bugs. I think I have finally won the
current battle and have not seem one for some some 3 weeks or so. I finally
adopted a kill or cure attack and spayed and watered the plants, every 2
days with Provado, at about half strength. All is now sweetness and light
with me and my Orchids. The foliage looks wonderful, (see Pict} as do the
flowers, the pict which for some reason refuses to attaché but will send
separately. I think I will adopt the method of one of our members? and spray
the plants and surrounds 2 or 3 times per year.
regards,
Ronbow.

From: Ron Bower
To: Orchid Talk List
Subject: Emailing: Ron Bower Orchids 31.3.07 074.jpg
Date: Mon, 23 Apr 2007 15:25

Hello, A rather nice unnamed hybrid, some 80mm + Ronbow.
The message is ready to be sent with the following file or link attachments:

Note: To protect against computer viruses, e-mail programs may prevent
sending or receiving certain types of file attachments. Check your e-mail
security settings to determine how attachments are handled.

From: francis quesada pallares
To: Orchid Talk List
Subject: Re: [OrchidTalk] This astonishing dendrobium...
Date: Mon, 23 Apr 2007 20:05

this ones remind me off Den. Stardust 'chiomy'. only
that they are yellow with a marroon throat, rather
than orange flowers.

> I wish I could say I grew it , but in truth I bought it in full flower 4
> weeks and 2 days ago , and this pic is taken today:-

From: Roy Lee
To: Orchid Talk List
Subject: Geoff's Dend
Date: Tue, 24 Apr 2007 09:15

I see there is an -mail also relating to this dend As Den Stardust. I found a pic of Den Stardust on a website.
I hope this link connects for you Geoff to compare with your plant.
http://zanaf.dyndns.biz/Hybrids/Den_Stardust.htm

From: Roger Grier
To: Orchid Talk List
Subject: Sea shell.
Date: Tue, 24 Apr 2007 09:35

Thanks for the information regarding the use of sea shell. I will read it in depth later on.

I have had an orchid [Dendrobium delicatum] growing in broken sea shell for three years now.

As I always say, place a piece of bark, a piece of broken clay flower pot and a piece of broken sea shell in your hand..........the size and shape are all the same. The bark will rot away..........the other two will not.

From: John Stanley
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shell. − and sermons
Date: Tue, 24 Apr 2007 12:55

Hi Rev.Gordon,
Here beginneth the second lesson!
Having rinsed away the bark residues, keep the clay pot fragment and the piece of broken sea shell in a damp enough environment for long enough and the sea shell will get lighter by solution whereas the clay pot will remain the same.
In other words, the sea shell (calcium/magnesium carbonate) will yield ions in solution of magnesium and calcium whereas the fired-clay won't.
The clay pot piece is virtually inert while the shell isn't.
That could be advantageous for lime-loving plants or disadvantageous for some others(?)
We'll let you have a break from writing tomorrow's sermon to let you wash your cassock and polish the lectern instead in readiness for Thursday's offering)
Here endeth the lesson.
(Oh, and please place any emails of advice about lime-loving orchids in the Orchid-Talk offertory box on your way out!)
John

From: Tina Stagg
To: Orchid Talk List
Subject: Sea shell
Date: Tue, 24 Apr 2007 14:40

About thirty years ago I bought some orchid bark with added sea shell. I used it to repot my very healthy cymbidiums and the whole lot died.

From: Mark R
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shell
Date: Tue, 24 Apr 2007 17:50

Sea shells are essentially pure calcium carbonate. I think a Paph
might like it but I imagine most epiphytes would hate it (I think).

From: Dennis Read
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shell.
Date: Tue, 24 Apr 2007 19:15

Was this a reply to a message on Orchid-talk or a private note. I did not receive any message from Gordon re sea shells. regards

> Thanks for the information regarding the use of sea shell. I will read
> it in depth later on.

From: Ron Newstead
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sharon's questions re my greenhouse
Date: Tue, 24 Apr 2007 19:20

From: Tina Stagg
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sharon's questions re my greenhouse
Date: Wed, 25 Apr 2007 15:15

Winter high is as warm as the sun takes it − or not much above 57F if it's a dull day. I don't use a day/night stat. Top vent opens at 75F up by the vent, which is about 70 at bench level. I would not expect the vent to open during Dec and Jan but we usually have plenty of sun by mid-Feb.

From: Ron Newstead
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sharon's questions re my greenhouse
Date: Wed, 25 Apr 2007 18:50

From: Dennis Read
To: Orchid Talk List
Subject: Sea shells
Date: Wed, 25 Apr 2007 19:20

I have been growing Ida costata (Lycaste longisapela) for many years to little effect -many small pseudobulbs and black marked leaves. A while ago in the OSGB magazine Henry Oakley mentioned that they grew on limestone cliffs. Having watered them with Calcium Nitrate solution I see the new leaves are a clear green. Any ideas where I can buy prepared sea shells in Devon?
I further understand that it is difficult for a fertilizer to include Calcium as it precipitates out. Is this correct?
Regards from a chilly and dry Devon ( my rainwater butts are empty) and the tap water is begining to taste foul.

From: Peter Fowler
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shells
Date: Thu, 26 Apr 2007 19:15

From: Dennis Read
To: Orchid Talk List
Subject: Roots
Date: Thu, 26 Apr 2007 19:25

For many years I have read and listened to many ideas on orchid roots. I eventually got round to reading my Orchid Review of March/April 2007 and found an article ''Back to your roots'. This is the most sensible article I have read about orchid roots.It is clear and does not gratuitously push any growing medium but clearly shows what an orchid requires.As the curret saying goes ' I commend it to you all to read'
Regards from a cold and dry Devon

From: John Stanley
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shells
Date: Fri, 27 Apr 2007 11:15

1. Molluscan sea shells contain both Mg and Ca unlike some other marine 'shells' such as sea urchins which are Ca carbonate only.

2.The fact that calcium carbonate can "precipitate out" is a testimony to the fact that it can be in a solution from which to precipitate! The solution of limestone, (calcium carbonate or calcium-magnesium carbonate) by weakly acidic groundwater, allows Ca ions to be in solution, albeit in small quantities. But then, don't plants use it only in very small quantities?

3. It occurs to me that freshly collected sea shells would almost certainly be contaminated with NaCl (common salt) and would need some soaking in fresh water before use with orchids. Could salt have been the problem for those having had bad experiences with shells.

4. Many dune sands from the west of UK are commonly shell sands formed from the wind transported shell fragments formed when empty shells are smashed in the surf (not all sand is quartz sand. Use a hand lens to distinguish the opaque whie-pink shell from grey translucent to transparent quartz,often with iron oxide coating.

5 There is nothing magical about shells, other than their appearance (when the orchids are dead they still look nice!). If plants need 'lime' then limestone chips/lumps will do.

6 Just a last thought, blackboard 'chalk' is mainly gypsum (calcium sulphate) whereas Chalk (the geological formation with a capital 'C' ) is mainly limestone.

From: Geoffrey Hands
To: Orchid Talk List
Subject: Re: [OrchidTalk] Reuters.com − Dutch flower growers aim to keep pace with the times − Sun Apr 22, 2007 9:42 PM ET
Date: Fri, 27 Apr 2007 17:40

I would think it would work well − I assume the calcium in the shells would
be pretty well locked up and not leach , so it would be much the same as
growing in clean gravel − a' la' Roger.

> Reuters.com − Dutch flower growers aim to keep pace
> with the times − Sun Apr 22, 2007 9:42 PM ET

From: Geoffrey Hands
To: Orchid Talk List
Subject: Re: [OrchidTalk] Emailing: Ron Bower Orchids 31.3.07 074.jpg
Date: Fri, 27 Apr 2007 17:40

From: Geoffrey Hands
To: Orchid Talk List
Subject: Re: [OrchidTalk] Geoff's Dend
Date: Fri, 27 Apr 2007 19:40

Incidentally, arrived home tonight after a week away , and its still going
well − just one or two flowers going over. Amazing.

> I see there is an -mail also relating to this dend As Den Stardust. I found
> a pic of Den Stardust on a website.

From: Geoffrey Hands
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shell
Date: Fri, 27 Apr 2007 19:50

I have , very belatedly , realized that the so-called "limestone paphs" are
0ften found growing on karst − yes it is limestone, and I know nothing about
its solubility , but it is very like marble or even glass .Very very hard .

Some marbles are in fact water soluble ( albeit slowly ) and others not .
The stuff they used to build the Taj Mahal is the "not" variety − still
perfect several hundred years after being built. The junk merchants in the
bazaars at Agra , sell tourist trash such as boxes made of "marble" made by
the same techniques ( they say) which will waste away in the winter damp ,
it's that soluble ; or so the stone workers near the Taj − claiming to use
the real McCoy , say − and they also make tourist trash , but at 10-50 times
the price, justified by them using the proper stuff which is mor3 expensive
and much more toil to work , but they guarantee their products for your
life-time....

But back to Paphs, if they grow on virtually insoluble limestone, what is
the point ; what do they get out of it ? I suppose that the answer is that
the low degree of solubility means that they get just the right amount that
they want ?

From: Geoffrey Hands
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shells
Date: Fri, 27 Apr 2007 20:05

As I understand the matter from conversations with two different fertilizer
manufacturers , over the years, they don't put in enough Ca or Mg ( for us
orchid growers , especially when we are using rain water or RO water )
because they know that 99% of their customers will be using tap water which
invariably contains enough of both , and in the right proportions too. And
or the customers will be growing in soil - in the ordinary meaning , which
also contains enough of those.

When we don't use soil; , and even worse don't use tap water, we must add .
You can use Calcium nitrate alone, or added to your mix, or look for a two
part fertiliser − where you have to mix something from bottle A and
something from bottle B. In my experience it has to be a liquid job − I have
never seen a two part powder fertilizer . 2-part mixes always contain enough
of both.

I think there is also or perhaps mainly problem in getting the Mag. Correct
, if the Calcium is correct ( when not using a 2-part mix) . Again , you
can add Mg from say Epsom salts ( which is Mag sulphate ) . The right ratio
of Ca to Mg by the way is about 4 to 1. I have in the past used Calcium
nitrate in one watering , a proprietary fertilizer in the next , plain water
in the third , and then sprayed with Epsom salts − say a good spoonful in a
gallon − as a foliar feed .

But two part mixes solve all these problems and are so easy to use ,
every watering.

You may have to go to a hydroponics supplier to get two part mixes − and you
don't have to use hydroponics techniques to use those fertilizers − of
course.

From: Ron Bower
To: Orchid Talk List
Subject: Re: [OrchidTalk] Emailing: Ron Bower Orchids 31.3.07 074.jpg
Date: Fri, 27 Apr 2007 22:10

Geoff,
I cannot see your screen but it looks right on my screen and yes it is a wow
and I was just being modest in saying that it was rather nice and not a
Mealy in sight.
Ronbow.

From: John Stanley
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shell (she sells)
Date: Sat, 28 Apr 2007 03:05

Geoff and others interested in lime,
While it is true that various marbles and limestones have different
solubilities, this is mainly because they vary in texture.
For example some of the oolitic limestones you'll recall from Boxhill days,
Geoff, are not tightly compacted nor recrystallised and water gets into the
pore spaces and has a large surface area to go at causing relatively rapid
solution. More indurated, compacted, purer limestone like the Carboniferous
of the Mendips is more resistant but still prone to dissolving (Wookey
Hole?). However, it has been around rather longer (300 my) than that of the
Jurassic (150my) and was dissolved to a great extent in Permian times (22 my
+) as well as being so at present.

When limestones are recrystallised under heat and pressure they cease to be
porous (although water might get into cooling cracks or joints)rendering
them permeable allowing dissolving water to pass through. High quality
marble, polished and used skilfully on buildings, tends to shed its water
before solution is much of a problem. Solution is also of course, less of a
problem in drier environments than the UK.

You can get a measure of the solution rate of a limestone/marble by looking
in a UK cemetary at any marble monument with inlaid lead (Pb) letters. They
will stand proud of the surface as the limestone dissolves back − the older
the more the letters stand proud. Tombstones are convenient for such
observations since they are usually dated.

There are many cheap 'marble' trinkets made from variations on gypsum −
which can be polished and can look v.similar but is much softer and often
weaker. Marble as a term used by gifte shoppe proprietors should be treated
with suspicion.

Your reference to 'glass' is more misleading though; most natural glasses
are silicate complexes and are almost inert in the environments exposed to
the atmosphere. I'm sure you know that glass is not really a material of any
given composition but a non-crystalline state caused when molten rock,
slag, or synthetic mineral complexes are quenched very quickly. Technically,
the traditional "stick o' Blackpool Rock" is (sugar) glass as are boiled
sweets. I doubt that very many orchid growers have tried either of those . .
other than to suck at as they re-pot, or play with their ukeleles

No calcium carbonate has a hardness of more than 3 on Moh's scale (about
that of a copper coin). Strictly, mineral hardness refers to the
scratchability of a single crystal face, not to the ease with which crystals
are separated from a rock aggregate by, say, percussion. Some limestones are
'tougher' in these respects than others but all are essentially of calcium
carbonate.
Hope this is of some use and not too off topic!
John

From: Tricia Garner
To: Orchid Talk List
Subject: Re: Roots
Date: Sat, 28 Apr 2007 17:05

> For many years I have read and listened to many ideas on orchid roots. I
> eventually got round to reading my Orchid Review of March/April 2007 and
> found an article ''Back to your roots'. This is the most sensible article
> I have read about orchid roots.It is clear and does not gratuitously push
> any growing medium but clearly shows what an orchid requires.As the
> curret saying goes ' I commend it to you all to read'

For the benefit of those who don't take the Orchid review, the article is
online. Visit

http://www.rhs.org.uk/learning/publications/orchidreview/orchid0307/orchidreviewmar2007.asp

From: Sylvain VAN DER WALDE
To: Orchid Talk List
Subject: Re: [OrchidTalk] Roots
Date: Sun, 29 Apr 2007 14:00

"Tricia Garner" wrote:
>
> For the benefit of those who don't take the Orchid review, the article is
> online. Visit
>
> http://www.rhs.org.uk/learning/publications/orchidreview/orchid0307/orchidreviewmar2007.asp
>
> and scroll down to the link to the file.

From: Dennis Read
To: Orchid Talk List
Subject: Biffrenaria harrisonii'Alba'
Date: Sun, 29 Apr 2007 20:05

Apols, for not responding earlier . When I was looking for a plant for Rocky I found one of my divisions had initiated a bud. I can now give my ideas on Biffrenaria harrissonii 'Alba'. As far as I cansee you grow it like mad from April to October in a mix of predomitably perlite with alittle bark and moss, getting the largest pseudo bulbs possible. Then you let it go dormant -only enough water to keep it from shrivelling. My plant has just flowered on a two year old bulb − not last years but the year before that. Previously I had just kept growing and feeding my plant. this made many bulbs but no flowers.
From the picture you can see it is an amazing flower, but I now have to work out how to get a presentable plant and long stems to show off the flower.
It was worth the wait to see such an amazigly pure flower.
Eegards from Devon after a fantastic day

From: jan
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shells
Date: Mon, 30 Apr 2007 06:20

So, if orchids need calcium and magnesium that much, where do the
epiphytes get it from, then? Especially in a rainforest (where any local
dust is likely to get washed out of the atmosphere by the daily rains)?
I read an article not long ago that claimed to have proved that the
Amazon received large quantities of dust blown over from a certain
valley in central Africa − perhaps this is the normal way?

From: Dennis Read
To: Orchid Talk List
Subject: Biff. harrisonii
Date: Mon, 30 Apr 2007 08:50

I have just read my note and I forgot to say that the plant that flowered was on a top shelf in the south west corner and the pot was very warm to handle.
Regards

From: Dennis Read
To: Orchid Talk List
Subject: Variations
Date: Mon, 30 Apr 2007 09:00

I have often wondered about variations in orchid flowers. The first picture is of my Lycaste Cassiopeia 'Wyld Peach'.. Each flower is about 14/15 cms wide but each lip is different as you can see in two cases of pictures attached. This is for interest but it shows the dangers of plant identification from a photo only.
This plant with many others will be on show at The Devon O. S. Show at Exmouth on Saturday 5th May.
Regards fromsunny Devon

From: Tricia Garner
To: Orchid Talk List
Subject: Re: [OrchidTalk] Roots
Date: Mon, 30 Apr 2007 09:10

From: Geoffrey Hands
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shells − and where do orchids get their nutrition ?
Date: Mon, 30 Apr 2007 09:35

Where orchids get their nutrition from is an old chestnut − all kinds of
ideas are put forward without any basis in fact, observation or experimental
evidence, even by very experienced and/or learned and sensible people.

Take that piece in Orchid Review, re roots, recently quoted. Full of good
sense EXCEPT that the author assumes that animal and bird faeces will
provide the nutrition. I have also heard one of our greatest living
orchidists say, in answer to a question, that root masses form kind of
baskets, which trap fragments of leaf, and these rot to form leaf-mould ,
etc. Fine ( in theory) but clearly not universally so − orchids with bare
roots and no trace of humus , running along rocks etc, are commonplace ; and
how does a seedling grow before it gets to have a basket of roots ?

The jungle is full of life? Not that full! The chances of one plant being
supplied with animal manure reasonably regularly are very very low, and it
would have to be regularly, since the rate of rain-fall would quickly wash
away any that did get deposited. ( In doing the experiments mentioned below,
I had a rain gauge set in the middle of a clearing holding about 3inches ;
it had overflowed, during the course of an a few hours work ! ). Again,
some trees can be seen with every inch covered with orchids and other
epiphytes, which could not conceivably be covered with animal manure at any
time.

These ideas about animals and birds are sheer speculation. In some cases it
seems that the authors have never been to a place where our orchids grow in
the wild, although that cannot be the answer for all the pundits who talk
such nonsense on the subject.

No, orchids are uniformly and universally supplied with nutrient in the rain
forest by the rain itself. This is why every plant along a branch can be
well fed − if they relied on bird droppings it would be much more random and
in some forests there would be a lot of starved orchids, or more likely no
orchids at all !

The rain starts as pure water, and does not − as it falls through the
atmosphere − collect anything useful by way of nutrients, or not very much,
but then it lands on the tree canopy, washes the tree leaves, and drips over
the orchids. The tree leaves carry traces of sap exudation − from the
stomata of the leaves. This occurs because, in order to maintain turgidity,
the trees (etc − I include all the plants) pump up their sap with a certain
pressure, and some "leaks" out. This tree (etc) sap contains nutrients which
the trees have taken up from the soil , so naturally it contains calcium and
magnesium (etc) in just the right proportions for plant growth. Of course it
does − it must − or you have poorly trees!

Proof ? I have been to the rain forest (in Thailand) with measuring jugs to
collect rain from the open sky, and also rain dripping through the tree
canopy onto the ground , and again actually dripping from the roots of
Dendrobium species. I then measured pH and EC from all the samples, and I
repeated the collection and measurement at different times; at the start of
a rain-storm, an hour later and another hour later − during continuous heavy
rain when several inches fell. I have given the figures here in the past -
sufficient to say that in my greenhouse I copy nature and use pH 5.8-6.2 and
EC about 600 − very different from the rain from open skies.

Moreover, the measurements that I was getting from the leaf drippings, were
very similar at all three times, indicating that it was not just the leaves
being washed clean ( at the start) but a continuous exudation being taken
up by the rain . As obviously it must be if the trees etc. are to maintain
turgidity.

Incidentally, at the London EOC some 5 (?) years ago, I listened to a
lecture by I think Professor Bruno, or some similar name (I do not have any
transactions, to check) and he was talking about what he called the
potassium cycle -I think it was radio-active tagged potassium which had been
tracked from the soil, traveling in the sap up vines, and being washed back
to soil (after exudation) in 24 hours. He was I think interested in the rate
of travel, but it is also an illustration of the fact of exudation. Of
course it would not be just the potassium which was exuded − it would be all
the sap nutrients literally being re-cycled, and if they happened to wash
over an orchid, why, then the orchid would get just what it wanted. Note -
most epiphytic orchids grow (leaves and especially roots) below the top
surface of the tree canopy, e.g. on the branches which support that canopy,
even if a few have flowers spikes extending above it.

From: Gordon Walker
To: Orchid Talk List
Subject: Re: [OrchidTalk] Variations
Date: Mon, 30 Apr 2007 11:55

From: Gordon Walker
To: Orchid Talk List
Subject: Geoff's piece
Date: Mon, 30 Apr 2007 12:00

Congrats Geoff a very easy to understand bit of knowledge you have passed on to us.
Gordon.

From: John Stanley
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shells
Date: Mon, 30 Apr 2007 13:40

Jan,
Depends on how much is 'that' much. Almost certainly their demands will vary
and some won't need 'that' much.
I seem to remember reading somewhere about the composition of rainwater
which collects all sorts of chemical goodies (as well as nasties) in trace
proportions on its way down. Also, passing avians and bats are pretty casual
in their ablutions and maybe they contribute a little too (or too little!).
Also, since non-epiphytes and other epiphytes may take up Mg and Ca, when
they, fall, decompose and add to the accumulating arboreal litter,could they
return their Mg and Ca to the system? Someone in this illustrious gang will
tell us . . . . . . .

Certainly S.African dusts find their way to Europe (I occasionally have a
pink car after a storm). These are mainly clays of which there are very
many of different compositions. Most have Mg in their makeup and a few have
Ca. I suspect (but aren't sure!) that they would supply traces which might
not amount to 'that' much . . . . but enough(?)

I have searched what books I have and, although sea- and fresh-water
compositions are commonly dealt with, atmospheric water, except by
implication, is little considered. However, there are a few quite heavy
(tedious rather than difficult I suppose) articles. This one:
http://neon.otago.ac.nz/chemistry/research/mfc/pubs/atmosphere/halstead.pdf
is an example of one that does at least give an idea of quantities except
that it, too,boils down to a case of 'that' much or 'that' little and we
really need to have an idea of what 'enough' or 'plenty' are in numbers.
Also, amount in a given volume of water means little without knowing
rainfall, run-off, evaporation/concentration etc etc. Really, we're back
where you came in; dust, atmosphere, washing out − onto epiphytes?
Clearly, epiphytes are successful and so they must get enough of the
elements they need from somewhere and that must be largely from above . .
Cheers
John

> So, if orchids need calcium and magnesium that much, where do the
> epiphytes get it from, then? Especially in a rainforest (where any local
> dust is likely to get washed out of the atmosphere by the daily rains)?
> I read an article not long ago that claimed to have proved that the
> Amazon received large quantities of dust blown over from a certain
> valley in central Africa − perhaps this is the normal way?

From: John Stanley
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shells − and where do orchids get their nutrition ?
Date: Mon, 30 Apr 2007 14:15

Geoff,
I agree with most of what you say except; "rain starts as pure water" not so sure about that but let's not get into a philosophical discussion of when it 'starts'. Certainly (certainly) it picks up many elements from the atmosphere and I'd speculate (I'm uncertain) that some droplets may condense by nucleating on clay dust, NaCl, pollen; but I'm guessing/surmising. See the article; http://neon.otago.ac.nz/chemistry/research/mfc/pubs/atmosphere/halstead.pdf I just whizzed off (via this forum) to Jan, which is one of (apparently) a very few on atmospheric water composition.

I also agree about the vaguaries of bird droppings, noting as I pass, however, the generous quantity of well-aimed Ptrodactyl guano that lands on my car every time I wash it (and the pollen, catkins, exuded sugar, dead aphids and leaves that stuff up the wiper mechanism, window slides and drain 'oles). I suspect that there is quite a volume of insectivorous and arachniferous faecal stuff as well. But this is unmeasured(?) and speculative when applied to epiphytic orchids. Maybe my car'd keep cleaner if parked in the local rain forest, and maybe all this stuff'd get "washed off" there(?).

I also agree that there is much verbal rubbish that has accumulated about roots. It is offered probably by 'authorities' whose speculation is converted to dogma by their readers on the strength of their well earned reputations in other spheres.

I suspect (but don't know) that the truth lies somewhere in the story of the processes by which cloud droplets (small and therefore of large surface area to volume) capture elements from clay particles and trace elements in the atmosphere. What I don't know (do you?) is whether or not these processes account for the quantities used by our epiphytic friends. In other words, credibility.

We get back to thinking aloud without experiment or quantitative evidence, as indeed you've just done. But until someone gathers info on how much concentration of Mg Ca is needed and how much water, of a given Ca, Mg concentration passes over the leaves/roots then that's about all we can do. I guess that the important thing is not to sound/seem pompously sure but to accept that all we can do is surmise . . . . until someone does the work (or their writings are discovered).

ps. why do you use Courier designed for steam typewriters and placing all characters in mesmerising columns rather than proportionally-spaced almost anything else?
John

From: Peter Fowler
To: Orchid Talk List
Subject: Bifrenaria harrisoniae var. alba 'Susan' CCC-AM/RHS
Date: Mon, 30 Apr 2007 14:40

This was my plant which I put forward to the RHS Orchid Committee; 32 fragrant flowers. First time a Bifrenaria harrisonia of any type had been awarded. Divided it up into many small plants at £1 a throw (early 90's). Requires lots of light and heat and a fairly long rest in the Winter.

From: Dennis Read
To: Orchid Talk List
Subject: Re: [OrchidTalk] Variations
Date: Mon, 30 Apr 2007 16:45

She is Molly, my greyhound x afghan lurcher cross. She was abandoned by 'travellers' and found starving. She is a great dog/bitch anda fantastic house dog. Nobody crosses our threshold without approval. Regards

From: Dennis Read
To: Orchid Talk List
Subject: Re: [OrchidTalk] Bifrenaria harrisoniae var. alba Â 'Susan' Â CCC-AM/RHS
Date: Mon, 30 Apr 2007 16:50

Peter, that looks like the plant that set me off. I think it is a fantastic bloom that shows all the required points of an orchid. Regards

> This was my plant which I put forward to the RHS Orchid Committee; 32
> fragrant flowers. First time a Bifrenaria harrisonia of any type had
> been awarded.

From: Geoffrey Hands
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shells − and where do orchids get their nutrition ?
Date: Mon, 30 Apr 2007 20:00

John, to reply to the most important point first of all , my e-mailer uses
Word 97 ( I think it's 97 − that was a vintage year) , with the default font
set to Arial !

Any suggestion of Courier impeaches my honour ( sorry if I'm a bit OTT − its
our wedding anniversary and a bottle of the bubbly stuff went down well ,
just an hour or so ago.} Maybe its your e-mailer which converts to Courier
?

Can we set them to fight it out, fonts for two at dawn , coffee ( with a
little Cognac in it please) for 1 afterwards. ? sorry...

And as for columns, I gave them up when I left the army − and that's more
than a few days ago . Maybe Tricia can make sense of the nonsense I'm typing
and make some suggestions − not that kind Tricia , remember , others may be
watching.

Now to turn to something more sensible − a technical argument. Ha ha , I
made my living with technical arguments − great stuff − I'll argue about
anything ( or at least I did when clients paid for my services at an
exorbitant amount per hour − although when I won , it was not exorbitant of
course ) . The flaw in your beautiful logic about pink dust and bird or bat
s*** on your car , is that I compared EC and pH between water falling from
an open sky , and water dripping from root tips . I also suspect that after
2 or 3 hours of constant heavy ( in fact, of course, tropical ! ) rain at a
rate of 30mm or more per hour , the sky would be pretty well washed clean of
dust − but the EC and pH changes in the water − comparing that falling in a
jungle clearing and that falling through the canopy, remained the same -
more or less. In the Geoff Hands theory of orchid nutrition, this proves
that all is derived from plant exudates .

Ps. Thinking it might be of interest more generally, I e-mailed Isobyl (
Editor , Orchid Review ) and now have a piece to prepare for that august
Journal − won't be ready for August I suspect , as first I have to find my
field notebooks , then some illustrations, but I'll get there one day.

From: Geoffrey Hands
To: Orchid Talk List
Subject: Re: [OrchidTalk] Bifrenaria harrisoniae var. alba 'Susan' CCC-AM/RHS
Date: Mon, 30 Apr 2007 20:00

A beauty of course , and so very well grown. I wonder if it was a piece of
that which I got from Peter White , flowers certainly very similar. There
may be a pic on my web-site, although I can't find that on the web , and
when I can spare the time I think I'll move it to a different host , the one
I use at present can't be called helpful when I have problems !.

From: Ron Bower
To: Orchid Talk List
Subject: Re: [OrchidTalk] Sea shells − and where do orchids get their nutrition ?
Date: Mon, 30 Apr 2007 20:55

Well said Geoff. I read the article in the Magazine which I get as a RHS member, and was not particularly impressed with it and frankly thought it as not up to the standard one expects from the RHS. It seemed to me to represent the efforts of some one who has been growing orchid for a few years (14) and had decided to pass on some observations. After a life time of growing many verities of plants, part as a professional, I am of the opinion that most if not all perform better when man has a hand in their environment and development. One only has to consider the improvement seen in Phalaneopsis in the short time I have been growing them to illustrate what I mean. Plants in the wild generally have to struggle to survive on a usually Spartan diet, just consider the improvements that can be seen in the fruit and vegetables that we eat, quite apart from the flowers most of which bear little reassembles to the standard what/that used to be excepted only as short a time ago as when I was a lad.

As Geoff and Rocky have said and illustrated most Orchids do not need soil, or bird droppings or decomposing leaves et al, water and something to hold on to, it seems, is quite adequate.

> Jan said − if orchids need calcium and magnesium that much, where do the
> epiphytes get it from, then?

MONTH	DATE	DATE	DATE	DATE	MONTH	DATE	DATE	DATE	DATE
January	1-7	8-14	15-21	22-31	February	1-7	8-14	15-21	22-28
March	1-7	8-14	15-21	22-31	April	1-7	8-14	15-21	22-30
May	1-7	8-14	15-21	22-31	June	1-7	8-14	15-21	22-30
July	1-7	8-14	15-21	22-31	August	1-7	8-14	15-21	22-31
September	1-7	8-14	15-21	22-30	October	1-7	8-14	15-21	22-31
November	1-7	8-14	15-21	22-30	December	1-7	8-14	15-21	22-31

2007 Archived Messages

22—30 April