pH etc..

[gego]

Spray with some Mancozeb. plus, reduce fertiliser level. Remember, Huntington (Brandon Tam , Lance Birk) fertilises with Ca-nitrate only. And they get good (sometimes fabolous) results.

Bjorn, I'm not convinced that nitrate is the native source of N with Paphs. In high altitude and almost wet all the time environment, nitrification is very minimal and with rain water flowing most of the time, this form easily get leached. Even my vandas don't like it. Leaves are yellowish and short. Spikes are short, stem in between flowers are short. Even the color of the flower is different, lighter and bland.

With just nitrates, it would be impossible to get the sizes these plants are capable of. If using inorganic, a mix of ammo/nitrate is better. Or urea/nitrate combo. But I'm seeing amino acids/urea/nitrate mix is very promising.

 

[Stone]

This is for Aussie Mike.

A couple of pictures, first one is of Doll's Kobold, the second henryanum.

Both had very dark green leaves for a while after deflasking.
Then earlier this year as they started to grow new leaves, they looked terribly light green, some even yellow with only vein left green.

I tried Cal/Mag a few times in a row at first, but nothing changed.
Then I poured some vinegar solutions, which I think helped with color almost immediately, but not very good result still as you can see.

Henry seedlings are slowly recovering, but Doll's Kobold seedlings still look terrible.
In the second picture, all the seedlings had two upper most leaves looking terrible, but as the leaves further develop and mature, green slowly returned.
This has not yet happened, or very little on the DK.

I would not discount the possibility that the coco chips are playing a part with the leaf colour there!

 

[Stone]

Remember the article "Ecology of Paph rothschildianum at the type locality in Kinabalu Park"? The soil chemistry of the rhizosphere of one roth loc 1 has 87mg/g of Fe and 2.4 mg/g of Mn. The foliar concentration showed an Fe of 0.03 mg/g and 0.024 mg/g, almost the same, although Fe is more than 400% more than Mn. Looks likes Fe in this location is way harder to take up than Mn. The pH was 6.7.

I do remember that. Iron was quite high in the geology yet a lot is probably unavailable. They did not specify what form of iron. Eg if iron oxide, it's more or less completely unavailable. pH 6.7 is not exactly low.

As iron and manganese are both affected by pH (reduced with increasing, increased with lowering), the leaf data provided by Xavier really suggests that either the iron in the (some) habitats is very low and/or the Mn is very high and/or oxidization of Fe is more common than of Mn.
Also the fact that Fe in fertilizers these days tends to be chelated, the optimum balance between the two could be being disrupted due to bicarbonates in the water affecting the Zn Mn and Cu sulphates etc and not the chelated Fe so much?
This whole chealted Iron thing came about because people couldn't keep their acid loving gardenias, azaleas and citrus green. Now they use it everywhere. I've been growing other plants for years with osomocote which is all sulphates and never have a much a colour problem.
The note at the bottom of the page is interesting supports this in a way.
http://www.spectrumanalytic.com/support/library/ff/Mn_Basics.htm

To solve the problem of having too much Fe and low Mn and Z, one option could just be adding more chelated Mn and Z at the same time raise the pH around 6.5 so Mo will be more available and Fe less.

Yes, unless the chelation favours the Fe as in the article above, where a foliar spray of Mn and Zn together with the cessation of chelates in our fertilizer might be more effective.
Or you can make your own formulation like Bjorn (which I can't do or would rather not dobecause I'm too lazy)

 

[Bjorn]

Bjorn, I'm not convinced that nitrate is the native source of N with Paphs. In high altitude and almost wet all the time environment, nitrification is very minimal and with rain water flowing most of the time, this form easily get leached. Even my vandas don't like it. Leaves are yellowish and short. Spikes are short, stem in between flowers are short. Even the color of the flower is different, lighter and bland.

With just nitrates, it would be impossible to get the sizes these plants are capable of. If using inorganic, a mix of ammo/nitrate is better. Or urea/nitrate combo. But I'm seeing amino acids/urea/nitrate mix is very promising.

No, I am not convinced either that nitrate is the chosen N-Source, actually one of my first postings on this forum was an appraisal how well urea(pure) worked in greening up things
the Cal-nitrate used by Huntintons is however not a pure Calciumnitrate, there is some ammonium in it as well (though jubelow 10% of N) Personally I use ammonium/ nitrate mix approx 2/1 so pretty high in ammonium.
Problems with nitrates could be connected to lack of molybdenum?

 

[myxodex]

No, I am not convinced either that nitrate is the chosen N-Source, actually one of my first postings on this forum was an appraisal how well urea(pure) worked in greening up things
the Cal-nitrate used by Huntintons is however not a pure Calciumnitrate, there is some ammonium in it as well (though jubelow 10% of N) Personally I use ammonium/ nitrate mix approx 2/1 so pretty high in ammonium.
Problems with nitrates could be connected to lack of molybdenum?

Yes, Bjorn and gego, I've been wondering about the same thing.

It also ties in with pH management issues. I think someone here previously posted the link (see below) to this paper on Catasetum fimbriatum, an acid growing species that uses glutamine and NH4 efficiently, but NO3 poorly. This research was conducted in in vitro culture, which is not ideal, but at least it was done with an orchid species.

The bit I found most interesting in this paper was that this plant acidifed the medium down to a pH in the 4.6 to 3.5 range depending on N source. With the nitrate and glutamine as N source the pH ended up at 4.6, but with NH4 it went to 3.5 ! The point is that the glutamine was less acidifying than the NH4, and comparable to the NO3. This makes sense as uptake of acidic and neutral amino acids involves proton symport, i.e. a H+ is taken up with the amino acid (same as with NO3). So maybe if we are looking for a non-acidifying source of reduced N, some amino acids could be the answer. The question then is whether the limestone paphs will use amino acids as efficiently as acid loving epiphytes ?

https://www.researchgate.net/public...idaceae_grown_with_different_nitrogen_sources

 

[Bjorn]

Amino-acids have been (and is) used amongst other sources is kelp extract being rich in amino-acids. So, I am convinced that amino-acids might be ideal, in many respects. One source of amino-acids could be lichen, moss and some cyano-bacter etc, which have been advocated for by Lance earlier.

 

[Stone]

I'm also a believer in organic N. It's part of the natural system and it's only natural that orchids use it. Especially those that grow like this!:
http://www.slippertalk.com/forum/showthread.php?t=40573&highlight=appletonianum+situ
I think there would be little in the way of nitrification going on there. I could be wrong....

 

[Happypaphy7]

I would not discount the possibility that the coco chips are playing a part with the leaf colour there!

Can you tell me more?
I am aware of coco chip being a cation exchanger.

Btw, others of the same cross in orchiata mix look the same.

 

[Happypaphy7]

I'm also a believer in organic N. It's part of the natural system and it's only natural that orchids use it. Especially those that grow like this!:
http://www.slippertalk.com/forum/showthread.php?t=40573&highlight=appletonianum+situ
I think there would be little in the way of nitrification going on there. I could be wrong....

Me, too!

The problem is how to apply it in home culture without too much smell. lol
In the past, Maudiae type hybrids did very well in the "rotten" mix.
I was never sure, of course, if it was because they were old and stronger, or if it was the natural fertilizer from the breakdown of the mix.
I'm talking no repotting for several years.
Then, you miss the perfect timing for repotting and the roots get all mushy. lol

 

[Stone]

Can you tell me more?
I am aware of coco chip being a cation exchanger.

Btw, others of the same cross in orchiata mix look the same.

Then it's probably something else but as I understand it, the fresh (or even treated) CHC can be extremely high in K and Na and very low in Ca and S.
High enough to cause imbalances with other elements. I'm testing some some which are now 3 years old and have had ferns growing in them. But not alone. They have the fern roots in them and I will add a bit of that to sphag and hard treefern. I think it could be a good product but not in the new/fresh state.
Try spraying your plants every few days with very weak Mn sulphate for a month and see if they green up.

 

[Stone]

I wouldn't recommend this but I have the time and space (and craziness) to do it.
This is the CHC which has been in a pot with the fern for about 2.5 years. (after the usual 3 month soaking in water with gypsum)
The fern grows very well in it. It is fed with osmocote and blood and bone.


The centre of the root ball.



It separates quite easily but most chips have fern roots penetrated through them.



After washing 3 times to remove a build up of humus along with the odd worm and other bugs.



The pH has now stabilized at about 5.8 from the original 7. (on the surface as well as inside the chips)


Theoretically, after 3 years of bacterial - and especially fungal action, it should now be quite safe to use. All of the easily rotted skin is gone and tannins no longer leach from it like when it is fresh.


The roots make the best of all basket lining material and is also good as a medium for many orchids too.


The fern can go back into a fresh pot of chc..

 

[PaphMadMan]

...
Try spraying your plants every few days with very weak Mn sulphate for a month and see if they green up.

I presume you mean Mg sulfate. Manganese (Mn) is an important micronutrient, but Magnesium (Mg) is probably what you want here.

 

[Happypaphy7]

I used cal mag a few weeks in a row with no effects.

Mike, where can one get Mn sulfate???
Or should I just spray mancozeb since it's mildly toxic?
No, I don't want to use anything toxic. I would freak out worrying about myself. lol

 

[gonewild]

I used cal mag a few weeks in a row with no effects.

A few weeks is not enough time to see results unless you used a heavy dose.

 

[Happypaphy7]

The label says it is.

 

[gonewild]

The label says it is.

Well then it must be true.

 

[Happypaphy7]

Thanks for sharing, Mike.

I would do it, but no space.

I wouldn't recommend this but I have the time and space (and craziness) to do it.
This is the CHC which has been in a pot with the fern for about 2.5 years. (after the usual 3 month soaking in water with gypsum)
The fern grows very well in it. It is fed with osmocote and blood and bone.


The centre of the root ball.



It separates quite easily but most chips have fern roots penetrated through them.



After washing 3 times to remove a build up of humus along with the odd worm and other bugs.



The pH has now stabilized at about 5.8 from the original 7. (on the surface as well as inside the chips)


Theoretically, after 3 years of bacterial - and especially fungal action, it should now be quite safe to use. All of the easily rotted skin is gone and tannins no longer leach from it like when it is fresh.


The roots make the best of all basket lining material and is also good as a medium for many orchids too.


The fern can go back into a fresh pot of chc..

 

[gego]

Very nice. Let us know how your plants grow on it.

Sent from my HTC One using Tapatalk

 

[Stone]

I presume you mean Mg sulfate. Manganese (Mn) is an important micronutrient, but Magnesium (Mg) is probably what you want here.

No, I mean Manganese sulphate. Mg deficiency always shows up in the old leaves first because it is very mobile. Mn tends to show up on the new - and particularly - newly expanded leaves.
Fe deficiency is similar to Mn but have another look at the Fe/Mn ratios in wild paphs in post 14 and 19 here.http://www.slippertalk.com/forum/showthread.php?t=7692&page=2
I think a Mn supplement would be a good starting point. A very dilute drench and/or spray.

 

[Stone]

I used cal mag a few weeks in a row with no effects.

Mike, where can one get Mn sulfate???
Or should I just spray mancozeb since it's mildly toxic?
No, I don't want to use anything toxic. I would freak out worrying about myself. lol

You can get it on ebay now I think. If not, get in touch with any citrus grower.
They will have it.