Dolomite lime for Paph. concolor

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John M

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I've got a friend who's concolor won't bloom. As well as directing her to Antec's Brachy care page, I suggested putting some limestone in the mix....not necessarily as a direct cure for not blooming; but, to help make the plant happy overall and maybe that will get it "thinking" about producing a spike. My question is: do you think that adding limestone or dolomite lime is useful and if so, how much dolomite should be added to the top of a 5" pot?
 
It was either Ray or Leo that brought up that "peletized" dolomite is really powdered dolomitic lime held together with a water soluable polymer. It falls apart almost instantly after the first watering, and can really jolt the pH.

I tried some of this out in a beaker at work, and yes it turns to mush almost instantly with a pH of 11.

I used maybe a 1/4 tsp in a 6" moss basket with one of my sanderianums when I started the basket experiment in Jan of this year. I didn't check pH initially, but was hovering in the low 6's about a month later. It probably washed out really fast.

I've been keeping my eyes open for some real dolomite for slower/longer release, but seems like the coops have all switched to the new and improved pelletized stuff, and I can't find any reasonable straight granular dolomite.

I've been perusing the aquarium trade, and found some real expensive stuff for african cichlid tanks.

PetSmart sells various Carrib Sea aquarium sand products. One is called "Cichlid Sand" . I think it was about $1 a pound and got a 20# bag of it. I can't get a confrimation what the % dolomitic lime content is, but it also has Argonite in it, which is a high % Ca material. I'll probably need to conduct my own testing with it to get the Mg content out of it.

I use it at roughly 1/4tsp per 4 inch moss basket with the "calcerious" paphs. If you've been folowing my thread on basket culture, things are going very well so far.

One thing that is consistently coming up in my research so far is that potassium is very rare in the soils of tropical rain forests. It gets cycled up into the leaf material (and back into the leaf litter) of plants, but never reaches the concentrations of calcium. Magnesium is often equal in molar concentration to K in tropical plant tissue.

Other litterature I've come across demonstatest that K is antagonistic to Ca and Mg, and the more you pour on, the more deficient the plants get in Ca and Mg. Since most of our balanced ferilizers come with lots of K, then you either need to add lots of Ca and Mg to the potting mix, or cut way down on the K in fertilizer. (After seeing all this info I've definitely quit with the Protekt).

Ca is difficult for plants to uptake relative to K and Mg. I have seen some good improvement in my plants with some shots of epsom salts (at least for getting rid of the excess K in the system), and then improving the access to Ca from the local mains water and potting amendments.
 
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I can get real dolomite and crushed coral at my local Petland. Unfortunately, every time I pull out a bag, its covered with mouse turds. So......Espoma pelletized dolomite it is......
 
I get dolomite in a powder form from Cape Cod Violetry. I top dress kovachii crosses every 3 months 1/4 tsp or less. In 2 days the leaves darken up nicely. I was using strictly RO water, but now have switched entirely to rain water. (Water and sewage bill has dropped $50 consistently :)The rain water I'm collecting from summer rains must contain nitrogen from lightning, as my whole orchid collection has "greened up".
 
I get dolomite in a powder form from Cape Cod Violetry. I top dress kovachii crosses every 3 months 1/4 tsp or less. In 2 days the leaves darken up nicely. I was using strictly RO water, but now have switched entirely to rain water. (Water and sewage bill has dropped $50 consistently :)The rain water I'm collecting from summer rains must contain nitrogen from lightning, as my whole orchid collection has "greened up".

Interestingly the rain water over karst areas in Malaysia also showed small amounts of Ca, Mg, and K ( presumably from dust). Overall the hardness of this rain was still very low (<5 mg/L as CaCO3). A year or so ago I switched from straight RO to 10% of my well water with RO. Hardness is about 20 mg/L as CaCO3.

There are some very successful growers in my area that use the local tap water just fine with a hardness of 80 to 100 mg/L. Analysis of this water indicates that it has about 25 mg/L of Ca, about 5 mg/L of Mg, and about 1.5 mg/L of K.
 
The following goes against conventional wisdom but is my experience with Paph concolor.

Until recently (the last couple of years) I haven’t had access to the range of potting media available in Australia so I’ve made do with what’s available locally.
For about 7 years we have been growing our concolors in native fern mix (similar to osmunda). This media usually has a ph of 5.5 – 6 when fresh but drops to as low as 4.5 within a few months. Repoting is generally done annually but some specimen size plants have gone 18 months - 24months.
As the plants are grown under shade cloth the plants receive heavy rainfall in summer and the occasional hand watering with rainwater in winter when its very dry.
Fertiliser is about ¼ strength applied heavily via foliar spray fortnightly during Spring and Summer.
I had thought about adding mag sulphate and cal nitrate to the fertilising program but then figured, why try to fix something that isn’t broke.

The results so far; I haven’t lost a plant in 7 years, beautiful health leaves, really great roots and regular blooming (often with a Spring and then an Autumn flush of flowers).

Regards, Mick
 
I think most people using plant parts as potting mix don't realize that that's were orchids get most of their nutrition to start with (in the jungle).

I wish I could upload some of these articles I'm finding, but most of a jungles nutrition is just recycled leaf litter with very little input from geologic sources.

This is particularly important for most orchids that grow epiphytically, in humus pockets or in forest duff.

The Ca/Mg/K ratio of plant leaves, bark, twigs, even roots is fairly similar for very wide ranges of habitat types.

So once your potting mix gets the right mix of bacteria and fungi breaking things down, your orchids are going to get Ca/Mg/K in the ratios that are almost universal for all plants. I found papers on the mineral content of sphagnum moss that show that sphag contains the same ratios of nutrients as other plants.

Quiet Australian also shows extreme prudence for application of fertilizer only applying at 1/4 tsp per gal for maybe 6 months of the year (every other week!). K accumulation is much less likely at that application rate and for the type of substrate he is using.

Contrast with many of us who may use (or used to use) 1/2 tsp weekly in summer to 1/4 tsp weekly in winter with a CHC material that is known to accumulate K like crazy. If using RO water, that K will stay there until the plants pick it up (or burns their roots off). If Mg sulfate is spiked into the irrigation water, it will flush the K out the mix, and get into the plant. K will also be offset with addition of some type of calcerous material in the potting mix, or increase of soluble Ca in the irrigation water. But Ca (unlike Mg) pretty much only gets into plants through healthy root structures, so if the plant gets behind the 8ball then Ca additions may be to little to late.
 
Some of these papers I'm presently looking at develop total annual nutrient budgets per hectare of forest.

From the paper on nutrient budgets for rainforest over karst formations in Malaysia the total input for Ca from rain, soil, and leaf litter decomposition (recycle). Is about 300 kg/hectre/year.

For a 10 cm soil/leaf litter depth that translates to about 300 mg/L/year of soil.

Generally Nitrogen is present at equal to 2 times the amount of Ca in leaf litter. So maybe up to 600 mg/L of N hits the forest floor per year.

So if we feed weekly at maybe 100mg/L N concentration into pots with X volume.......with 52 weeks in a year.....you can guess that we tend to feed our greenhouse orchids at much higher rates than they would get to eat in the wild.

K in leaf litter is even a much smaller fraction than N or Ca, so using a balanced NPK fertilizer we are really plowing huge amounts of K into our potted slippers (relative to what they receive in the jungle).
 
Rick, isn't that the point? Wild plants adapt to what's available, not what's optimal.We are trying to grow our plants faster, bigger and better than nature so they need more nutrition/light/CO2/water per unit time. For instance line bred species are said to be 'easier' to grow than jungle collected plants. To me that means they grow faster and are more disease resistant and flower earlier/younger - hence the need for more nutrition.
I agree we don't know the balance or specific amounts. That will only come with scientific trials of various elemental combinations. With paphs we are at a distinct disadvantage because, unlike cymbidiums, we can't subject batches of clones to various treatment/growing options to find the best results. Further the genetic diversity in the genus paphiopedilium would suggest there wont be one right answer. Then we cross brachys with multies just to complicate it all....
It might be interesting to do a leaf composition analysis on a jungle plant vs a well grow cultivated plant of the same species. Any one with a mass-spectrometer?
 
Rick, isn't that the point? Wild plants adapt to what's available, not what's optimal.We are trying to grow our plants faster, bigger and better than nature so they need more nutrition/light/CO2/water per unit time. For instance line bred species are said to be 'easier' to grow than jungle collected plants. To me that means they grow faster and are more disease resistant and flower earlier/younger - hence the need for more nutrition.

Actually I find that organisms optimally evolve to conditions that they can live in non-competitively, making restricted range organisms much less adaptive to change. If your above theory was correct, then we would find paphs growing like weeds in agricultural areas, and all the plants in our GH's would all be monster specimen plants.


The paper on plants growing over serpentine was especially enlightening. Serpentine has tons of Mg, low Ca, lower yet K and PO4. Yet for the 30 or so trees analyzed non are "adapting" but all are modifying their intake to balance their ions for optimal metabolic requirements. They end up with high Ca, lower and even Mg and K, and more P than found in the soil. As the authors point out, the "adaptive evolution" is to evolve protein and enzyme systems that can manipulate the external environment to make it optimal for the internal environment. However these enzyme and protein systems are now in their genes, and most of these species are now stuck living over serpentine, and will never be competitive in a cornfield no matter how much fertilizer you pour on them.
 
It might be interesting to do a leaf composition analysis on a jungle plant vs a well grow cultivated plant of the same species. Any one with a mass-spectrometer?

Wasn't that the whole point of the MSU fertilizer with Phalaes? Actually I don't think they ever compared to a wild plant, just a well grown GH plant.

Lots of us (including myself) are using MSU fert, but obviously its not working adequately or our expectations are too high.
 
Rick, isn't that the point? Wild plants adapt to what's available, not what's optimal.We are trying to grow our plants faster, bigger and better than nature so they need more nutrition/light/CO2/water per unit time. For instance line bred species are said to be 'easier' to grow than jungle collected plants. To me that means they grow faster and are more disease resistant and flower earlier/younger - hence the need for more nutrition.
I agree we don't know the balance or specific amounts. That will only come with scientific trials of various elemental combinations. With paphs we are at a distinct disadvantage because, unlike cymbidiums, we can't subject batches of clones to various treatment/growing options to find the best results. Further the genetic diversity in the genus paphiopedilium would suggest there wont be one right answer. Then we cross brachys with multies just to complicate it all....
It might be interesting to do a leaf composition analysis on a jungle plant vs a well grow cultivated plant of the same species. Any one with a mass-spectrometer?

Xavier has done some work on leaf analysis. The thread below is worth a look.
http://www.slippertalk.com/forum/showthread.php?t=7692

Regards, Mick
 
Actually I find that organisms optimally evolve to conditions that they can live in non-competitively, making restricted range organisms much less adaptive to change. If your above theory was correct, then we would find paphs growing like weeds in agricultural areas, and all the plants in our GH's would all be monster specimen plants.

That's a gross exaggeration of my argument. But goes to my point - they aren't the same plants; wild vs greenhouse line breds or hybrids. The plants we grow that are line bred grow larger, more flowers and flower years earlier than the the majority of jungle collected plants. That seems to be most peoples impression of Paph. rothschildianum and delenatii line bred plants (as examples). Look at modern cymbidiums - multispiking, flower in 3 years. They don't do that in nature. In the case of humans, we are nearly 10-15cm taller than 200yrs ago - same species, same genetic makeup, but with removal of nutritional restrictions (gone too far the other way , in fact) and elimination/treatment of disease.
The term 'hybrid vigor' has meaning. We have selectively bred plants that are less bound by their habitat and natural restrictions. They MAY not have the same requirements. That's all I'm saying. So, while studying their natural requirements is the sensible place to start, it may not provide the answers to getting the best out of 'modern' plants. Scientific application of theories and trial and error are.
 
Wasn't that the whole point of the MSU fertilizer with Phalaes? Actually I don't think they ever compared to a wild plant, just a well grown GH plant.

Lots of us (including myself) are using MSU fert, but obviously its not working adequately or our expectations are too high.

Has someone actually done the experiment? The next step after that would be do alter one nutrient at a time to determine which is rate limiting and redo the analysis.

Yes, we are all greedy - bigger, faster, better.
 
Repotting thousands of plants alone so I am not in a funny mode...

However:
- dolomitic lime, or the lime we want to use is calcium/magnesium carbonate, CaCO3 MgCO3. Usually it dissolves only according to the acidity of the environment, therefore, if you put real carbonate lime in water, you should expect a pH of at most7.5.
- when pelletized, dried, or whatever, if you get a high pH, like 9, it means the calcium carbonate has been partially converted in calcium hydroxide ( same for magnesium), and it is not what you want.

I went further than anyone else in the world with foliar and root analysis. Some results start to be more clear, however:

- At 100ppm N, MSU provides way more micronutrients than a Peters or Plant Prod. I think it is one of the reasons why people got 'amazing results' with MSU at first.
- MSU is not suitable for many growing environments. I agree it can work with some potting mixes, but for me and some other people ( including the largest phal seedling grower in the world in the Netherlands), it proved to be a mess, plants would grow slowly after a while. All the serious professionals agree that a ratio NH4/NO3 has to be matched to the crop being grown, and MSU is nearly only nitrate, pretty useless for some species and even toxic ( nitrate increases the requirement of molybdenum by the plant, something some species cannot cope with as they don't take molybdenum at a regular rate).

Fern roots + rain releases something that can make the paphs grow very well, actually a gas ( ammonia). I think many paph species evolved to take up ammonia through the roots, in fact I have evolved a new setup and growing conditions, and the plants have never been better... At least for some species.
 

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