Several of my dendrobes (moschatum, phalaenopsis hybrid, pierardii)
are showing noticeable reddening of pseudobulbs & foliage.
I believe this is typically due either to too much sun or to a
nutrient deficiency. In this case I doubt sun is a problem.

I have read an explanation of the nutrient deficiency - can't remember
where, or what the cause was.

Can anyone advise, & if possible point me at an on-line elaboration on
the problem please.

Dave Gillingham
------------------------------------------------------------------------------
To email me remove the .private from my email address.

I have a brief description of the functions of, and symptoms of mineral
deficiencies posted - check out "Plant Nutrition" under the Free Info link
at the URL below.

--

Ray Barkalow - First Rays Orchids - www.firstrays.com
Plants, Supplies, Books, Artwork, and Lots of Free Info!

.. . . . . . . . . . .
"Dave Gillingham" wrote in message
...
Several of my dendrobes (moschatum, phalaenopsis hybrid, pierardii)
are showing noticeable reddening of pseudobulbs & foliage.
I believe this is typically due either to too much sun or to a
nutrient deficiency. In this case I doubt sun is a problem.

I have read an explanation of the nutrient deficiency - can't remember
where, or what the cause was.

Can anyone advise, & if possible point me at an on-line elaboration on
the problem please.

Dave Gillingham
--------------------------------------------------------------------------
----
To email me remove the .private from my email address.

Thanks for your response, Ray.
After checking out "Plant Nutrition" on your website, I assume my
problem may be low phosphorus?
If so, will a higher P fertiliser reverse the colouration, or only
improve it for new growth?

On Mon, 20 Oct 2003 16:23:42 -0400, "Ray"
wrote:

I have a brief description of the functions of, and symptoms of mineral
deficiencies posted - check out "Plant Nutrition" under the Free Info link
at the URL below.

Dave Gillingham
------------------------------------------------------------------------------
To email me remove the .private from my email address.

Unless you're nutrient supply has little-to-no phosphorus, that is an
unlikely reason for the coloration. Nitrogen, phosphorus, and potassium
salts are relatively cheap, so are usually in a fertilizer in abundance. I
don't know if the coloration is reversible, but it's worth a try.

The June AOS "Orchids" magazine had an article about a Michigan State
University study in which they challenged the need for high phosphorus for
blooming. Their formula has only 3% P2O5, and that's apparently enough - my
plants have seen nothing but the MSU formula for about 6 months now, and
they're all doing fine.

--

Ray Barkalow - First Rays Orchids - www.firstrays.com
Plants, Supplies, Books, Artwork, and Lots of Free Info!

.. . . . . . . . . . .
"Dave Gillingham" wrote in message
...
Thanks for your response, Ray.
After checking out "Plant Nutrition" on your website, I assume my
problem may be low phosphorus?
If so, will a higher P fertiliser reverse the colouration, or only
improve it for new growth?

On Mon, 20 Oct 2003 16:23:42 -0400, "Ray"
wrote:

I have a brief description of the functions of, and symptoms of mineral
deficiencies posted - check out "Plant Nutrition" under the Free Info
link
at the URL below.

Dave Gillingham
--------------------------------------------------------------------------
----
To email me remove the .private from my email address.

Dave,

The following is from experience with Phals so it may or may not apply. In
addition, I tend to see phosphorus problems more in the spring, but that
could just be my growing. I see more phosphorus problems than any other
nutrition problem. I wish it was more uncommon around here than it is.

The purpling starts with the older leaves and slowly moves to the new
growths. Leaves getting more sun will tend to purple first although the
plant is not receiving too much light. In the worst case, growth stops,
lower leaves start turning a purple/red/brown. With time it will kill
plants but it is a slow death.

First, check your roots. If the plant has a severely damaged root system,
it may show up as a phosphorus deficiency. If your roots are ok and you
have been feeding regularly it is likely a problem with the pH in your mix.
Plants have a hard time taking up phosphorus when the mix pH is between 7.5
and 8.5 or less than 4.0. If you are using Rain or R.O. water it is pretty
easy to get the mix pH under 4.0. If you have hard water and do not flush
enough, it is pretty easy to get your mix in the 7.5 - 8.5 range. Using the
wrong fertilizer for your water/mix can cause either case. When I see signs
of problems I run a little R.O. water through the pot and measure the pH of
what comes out.

If the problem is being caused by a pH problem, double flush the mix. If
you expect it is a low pH problem try using a Cal-Mag fertilizer for a
while. If you expect it is a high pH problem try a bloom booster
fertilizer. The first will raise the mix pH the other will lower it, so
pick carefully. I also start misting with a balanced general purpose
fertilizer that is pretty pH neutral a couple of times of weeks. If this is
the problem the plant will turn around fairly quickly (improvement seen in a
couple of weeks). All but the very worst purpling will return to its normal
color with time.

If this was problem, you will need to look to your water and fertilizer and
make some changes. The above is corrective but not really a long term
solution.

Pat Brennan
Brennan's Orchids

From sunny south Florida -- are you sure you have a problem at all? Around
here, we consider a bit of pigment showing in the foliage to be a "healthy
suntan." I have one client who was keeping her [one live] den with her
phals, and then complaining that they never bloomed ... I moved it out into
brighter light, it started showing some red-purple in the foliage, and
promptly put on an incredible growth spurt.

The most common nutrient deficiency that we see is magnesium, and applying a
bit extra [preferably chelated, but in a pinch Epsom Salts will do] will
help to green up both pale and reddened foliage.

Good growing,

--
Kenni Judd
Juno Beach Orchids

http://www.jborchids.com
"Dave Gillingham" wrote in message
...
Thanks for your response, Ray.
After checking out "Plant Nutrition" on your website, I assume my
problem may be low phosphorus?
If so, will a higher P fertiliser reverse the colouration, or only
improve it for new growth?

On Mon, 20 Oct 2003 16:23:42 -0400, "Ray"
wrote:

I have a brief description of the functions of, and symptoms of mineral
deficiencies posted - check out "Plant Nutrition" under the Free Info
link
at the URL below.

Dave Gillingham
--------------------------------------------------------------------------
----
To email me remove the .private from my email address.

Hey Kenni,

How does a magnesium deficiency show its ugly face? Does it come on fast?
We use a lot of Cal-Mag fertilizer here and I do not think I have ever seen
it.

Pat

"Kenni Judd" wrote in message
.. .
From sunny south Florida -- are you sure you have a problem at all?
Around
here, we consider a bit of pigment showing in the foliage to be a "healthy
suntan." I have one client who was keeping her [one live] den with her
phals, and then complaining that they never bloomed ... I moved it out
into
brighter light, it started showing some red-purple in the foliage, and
promptly put on an incredible growth spurt.

The most common nutrient deficiency that we see is magnesium, and applying
a
bit extra [preferably chelated, but in a pinch Epsom Salts will do] will
help to green up both pale and reddened foliage.

Good growing,

--
Kenni Judd
Juno Beach Orchids

http://www.jborchids.com
"Dave Gillingham" wrote in message
...
Thanks for your response, Ray.
After checking out "Plant Nutrition" on your website, I assume my
problem may be low phosphorus?
If so, will a higher P fertiliser reverse the colouration, or only
improve it for new growth?

On Mon, 20 Oct 2003 16:23:42 -0400, "Ray"
wrote:

I have a brief description of the functions of, and symptoms of mineral
deficiencies posted - check out "Plant Nutrition" under the Free Info
link
at the URL below.

Dave Gillingham

--------------------------------------------------------------------------
----
To email me remove the .private from my email address.

Thanks to all who have responded - greatly appreciated.

On Mon, 20 Oct 2003 21:44:08 +1000, Dave Gillingham
wrote:

Several of my dendrobes (moschatum, phalaenopsis hybrid, pierardii)
are showing noticeable reddening of pseudobulbs & foliage.
I believe this is typically due either to too much sun or to a
nutrient deficiency. In this case I doubt sun is a problem.

I have read an explanation of the nutrient deficiency - can't remember
where, or what the cause was.

Can anyone advise, & if possible point me at an on-line elaboration on
the problem please.

Dave Gillingham
------------------------------------------------------------------------------
To email me remove the .private from my email address.

Dave Gillingham
------------------------------------------------------------------------------
To email me remove the .private from my email address.

Usually, gradual fading of green color beginning at the junction between
leaf and pb, and progressing up the leaf. But if you are applying Cal-Mag
regularly, I doubt that's your problem [assuming it's a problem].

Red/purple "discoloration" has almost always been, in my experience, either
"suntan/sunburn" depending on one's definition, or minor cold damage [hard
to imagine, this time of year, at least for me here in still very warm south
Florida].

--
Kenni Judd
Juno Beach Orchids

http://www.jborchids.com
"Pat Brennan" wrote in message
...
Hey Kenni,

How does a magnesium deficiency show its ugly face? Does it come on fast?
We use a lot of Cal-Mag fertilizer here and I do not think I have ever
seen
it.

Pat

"Kenni Judd" wrote in message
.. .
From sunny south Florida -- are you sure you have a problem at all?
Around
here, we consider a bit of pigment showing in the foliage to be a
"healthy
suntan." I have one client who was keeping her [one live] den with her
phals, and then complaining that they never bloomed ... I moved it out
into
brighter light, it started showing some red-purple in the foliage, and
promptly put on an incredible growth spurt.

The most common nutrient deficiency that we see is magnesium, and
applying
a
bit extra [preferably chelated, but in a pinch Epsom Salts will do] will
help to green up both pale and reddened foliage.

Good growing,

--
Kenni Judd
Juno Beach Orchids

http://www.jborchids.com
"Dave Gillingham" wrote in message
...
Thanks for your response, Ray.
After checking out "Plant Nutrition" on your website, I assume my
problem may be low phosphorus?
If so, will a higher P fertiliser reverse the colouration, or only
improve it for new growth?

On Mon, 20 Oct 2003 16:23:42 -0400, "Ray"
wrote:

I have a brief description of the functions of, and symptoms of
mineral
deficiencies posted - check out "Plant Nutrition" under the Free Info
link
at the URL below.

Dave Gillingham


--------------------------------------------------------------------------
----
To email me remove the .private from my email address.