Media for Paphiopedilum

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This post is to discover what media is more effective for which Paphiopedilums. I can only provide my research and its conclusions of my Paphiopedilum plants and their media, but as for anyone elses plants and media, I can not account for. This is to give a basic understanding upon relationships and the effectiveness of what Paphiopedilum media is made up of. I provide information on some of the components to make some of the media, but effectiveness is not gauranteed. Different factors effect the results of the effectiveness of the media. A single medium that is used by a "windowsill grower" will not have the same results as a "greenhouse grower", as conditions effect the outcome of the media. If there are better alternatives than these, please post, it is great to learn from others. Please message me or leave a comment about any mistakes or clarifications.

The first factor to consider when repotting a Paphiopedilum is "why?". Most people are accustomed to repotting their orchids at a certain time of year, or when it is convenient for the plant. Repotting induces expansion and growth, and reduces stress and struggle, so it is usually nessecary to repot to mantain healthy plants. But on Paphiopedilum plants, it is almost the complete opposite. One must find out how these elusive beauties grow in nature to grasp a full understanding on how to cultivate them.

First question a person must ask is where Paphiopedilums grow in nature and why they grow there. The answer is relatively complex, but the explanation is rather simple. Paphiopedilum plants normally grow in humus or on dead trees. There is a reason for growing in such dumb spots, why not on the side of a live tree, or on a beautiful rock suitable for a lithophytic dweller? It is what makes the natural media that the Paphiopedilum seeks out. Symbiotic fungi decompose dead material into usable, organic matter. These same fungi also make humus and convert the cellulose from the dead wood into usable sugars. This is what separates the Paphiopedilum plants from the rest of the orchids. Most other tuberous orchids seek tree roots, where Mycorrhizal fungi dwell, and eventually the fungi mycellium spread out to surround and enter the orchid tubers. Paphiopedilums depend on the Sybiotic fungi to help keep the plant alive. The Symbiotic fungi surround the roots of the Paphiopedilum, but do not enter inside. The term applied here is 'commensalism', where the plant benefits, but the fungi are left alone and unharmed. The waste product of the Symbiotic fungi is either the nutrients left behind in the humus, or in the sugars in the dead wood, which the Paphiopedilum needs. When there is no more dead material or cellulose to convert, the fungi usually dies. Ultimately, the Paphiopedilum slowly uses up the last of the waste products, and also dies. So, the decomposing media in a cultivated pot of Paphiopedilum is normally wanted, not unwanted as in most other pots of orchids. But obtaining the right materials that the fungi like induces fungi growth, which results in Paphiopedilum growth.

Some things to be considered when selecting materials for a new Paphiopedilum medium include what conditions the Symbiotic fungi survive in and what they decompose faster. Symbiotic fungi dislike sunlight, the fungi actually decomposes at the sight of sunlight. These fungi are more "behind the scenes" workers, and tend to stay inside and hidden just below the top layer.

These Symbiotic fungi need to stay damp at almost all times, and in a relatively room temperature surrounding. When conditions are dry, they venture deeper into the ground, or in cultivation, the pot. A nessecary component for retaining water is perlite or cocoanut husk. The best component is humus, where the fungi are already growing and thriving, but a person must venture into the woods and dig under old leaf debris to find humus. Humus also retains water for a long time, but when dried out, it simply turns into dirt, and is almost impossible to reverse the effects. The fungi keep the humus, humus. Humus is basically "alive". But if there is no humus available, use some dirt from a shady spot, or even compost, then mix the husk and/or perlite in. This is your base medium for the Paphiopedilum.

The next component is the "food", what the fungi are going to convert into nutrients or sugars for the Paphiopedilum plant to obtain. Cocoanut husk, as I mentioned previously, is a very good component for retaining water, and also for being decomposed. The cellulose fibers of the cocoanut husk allow it to be easily accessed by the fungi, and be decomposed at a quick rate. Another component may also be small, chopped pieces of leaf litter. These are the dead leaves, I recomend either Oak (Quercus sp.) or Maple (Acer sp.). Chopping the dead leaves into smaller pieces allows quicker entry access into the sides of the leaf to decompose rapidly. These are to be added with the base medium for the Paphiopedilum.

Some other optional components that do not hinder the fungi may include tiny pieces of limestone, small pieces of mulch (remove from about 3cm deep, usually contains Symbiotic fungi), and small broken up twigs. These can be mixed also with the base medium.

Basically, the medium for a Paphiopedilum can be compared to organic gardening, and utilizing natures "trash" and "trashmen" (dead material and the decomposing fungi).

The last component is charcoal. I suggest two types of charcoal options, and a charcoal additive. Though charcoal is nothing more than burnt wood, it still serves as a nutrient rich component. There are two ways to give your Paphiopedilum charcoal. A person can either get charcoal pieces (the finer, the better), or can burn their own paper and have charcoal flakes (make sure the paper is black, and not grey), either way works just fine. The charcoal, instead of being mixed inside the medium, will be placed on the top layer of the pot. This is so it will break down from the top of the roots on downward. Then, have some charcoal pieces, about 1/4 of a cup full, and crush them into a very fine powder. Simply sprinkle it everywhere on top of the charcoal in the pot, and then afterwards, water it in. The powder will slowly make its way down to the base medium, where it can be further utilized.

Media to avoid with Paphiopedilum plants are Sphagnum Moss and Bark. Sphagnum moss cannot support a Paphiopedilum for long, when the moss dries out, the few fungi that live in the moss quickly die. Bark is basically used for epiphytic orchids to grasp upon. Sometimes, but rarely, fungi is growing in or on the sides of the bark chips. They provide a Paphiopedilum plant no efficient purpose.

Here is where my research is still in progress. This research on fertilizer's relationship with orchids can be disregarded, if wanted, because I am still working on hard evidence and statistics on these observations.

I have researched so far that fertilizer does nothing directly to an orchid plant. The fertilizer usually effects the microbes which live on or around the plant, or even in the air (these include fungi, algae, and bacteria), which indirectly creates commensalism between the microbes and the orchid. When fertilizing an orchid, the fertilizer does not absorb into the velamen of an orchid root. The velamen is a semi-permeable substance which allows water molecules and smaller molecules to pass by. All other molecules build up a residue on the surface of the orchid root and medium. Fertilizer is a great "energy drink" for algae, which you may notice on your orchids if you keep them wet enough. Though the fertilizer does nothing for the orchid, it promotes the spawning and growth of algae and other microbes. The algae is a very strong, but plant safe, natural fertilizer. The fertilizer may also feed the Symbiotic or Mycorrhizal fungi found within the pot, which may help the orchid plant. Fertilizer is a very dangerous substance, which can cause cancer, twitches, severe bacterial infections, death, and many other health problems. The natural algae fertilizer is a better alternative than the dangerous man-made fertilizers commonly used. Besides the algae's efficiency over man-made fertilizers, it is safer for other organisms also, and does no ruin water supplies (permanently). I am still to prove all of this, but most of this is correct.

As I mentioned before, this will work for some people, and some people it won't work. Sometimes, the fungi will dislike the temperature, the surroundings inside the pot, or even watering conditions. The main thing to focus on growing with Paphiopedilum is the fungi, and not so much the plant. The Paphiopedilum will do its thing accordingly and as directed by the fungi and their condition.

Please let me know if this is useful information. If you are going to try this medium, please use it on a replaceable or dispensable Paphiopedilum plant, maybe your conditions are not ideal for cultivating this fungus, and your plant may die as a result. I am not trying to scare anyone, but see the difference with the "before and after" switching to a more fungi-rich medium. I had a small Paph. malipoense, near death, and am growing it with my medium in shade with the temp. around 90F constant, and is thriving. Same with my rare form of Paph. micranthum and Paph. armeniacum. The medium works very well for me, and I am now deciding to share the secret to my superior Paphiopedilum success. I use the same ingredients of this medium to grow my plants of Triphora gentienoides, which is an impossible orchid to grow outside of its natural location.

-P.A. Mahon
I'm not a good person to ask this question to, as the fungal relationship with the roots is the last thing I worry about. I prefer inorganic media and nearly no supplimented nutrients. I have lost more plants to added nutrition than to minimal sustinance, and the growth is not that different in my experience. Again this is just me.

The seeds need fungi to sprout before they can manufacture their own food, but adult photosynthetic paphs seem to do fine in microbial poor conditions in my culture. When using organic materials to promote decomposing microbes, you are doing a very risky balancing act between beneficial ones and potentially disastrous ones that attack living tissue. Pockets in organic mixes like humus go anaerobic quickly and produce toxins that will kill the roots you are trying to make happier with the decomposing matter. The key to success in both cases is plenty of aeration around the roots to prevent the anaerobic microbes from producing too many toxins. This is why repotting is so important since mixes break down and produce situations that allow these microbes to grow quickly and produce their toxins thus inhibiting or killing root tissue.

In the wild there is a very complex system of checks and balances that allows these plants to grow without too many troubles. Imitating this in artificial conditions is risky, but if it works for you then it is worth experimenting with. I have been experimenting with very nutrient poor conditions focusing on a balance of aeration and moisture instead and have been getting rather good results without the negative side effects of destructive microbes common in organic medias.

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You have some very good points and information. Conditions are a very big factor for the microbial relationship with the Paphiopedilum roots. And also location of where the microbes were picked up from will produce either good or detrimental results.

Humus and soil is always a risky medium for any plants, the microbes in the ground are usually unknown. But I have found that most of the plants I put in a humus mix (like some of my tropical Begonia or other plants) never seem to grow. The humus at first does inhibit fast action growth for any orchid, but within a week, the humus backfires and kills the plant. But I have noticed on the Paphiopedilum plants, the same is not said. I cannot say the same for Phragmipedium, Selenipedium, or Cypripedium. There are a few exceptions to my microbial based media, like volcanic lithophytic dwelling Paphiopedilum species, or maybe one that grows on the beach (like the Catasetum in Rio de Janiero).

I am unsure why I have not encountered the bad microbes, maybe Paphiopedilum has an affitinity towards certain species of Sybiotic fungi, and maybe these same fungi kill off other harmful microbes. I am unsure, and am still researching.

I though I would share this medium for testing, because it has been way too effective for me to even comprehend. I appreciate the comments, and will take these into consideration. Any other comments or questions are welcome, learning from other's research and mistakes is what learning is all about.

-P.A. Mahon
I have a question regarding the posts above:

If fertilizer cannot be absorbed through the velamen, then how does the plant absorb nutrients at all? To me it would seem that the roots must be permeable to ions or else they would never be able to absorb anything but water from thier environment, and I'm pretty sure that they need to be able to transport many substances back and forth between the roots and their surroundings. Fertilizer is really just a dilute solution of various salts such as ammonium nitrate, and I thought that plants underwent nitrogen fixation (converting inorganic nitrogen in the environment into organic nitrogen compounds such as proteins) by first absorbing it through the roots. Am I wrong here? It's been a long time since I took any chemistry classes...

This is where I am still researching. The fertilizer does not seem to be absorbing into the velamen of the roots. Fertilizer is not always a very complex molecule, but I am assuming only elements and smaller molecules may pass through. Microbes like bacteria usually fix N2 into usable N, but I am unsure about all the other plants and orchids. Maybe on orchids, like I stated, the algae, bacteria, fungi, or any other present microbe may absorb the fertilizer, and convert the fertilizer into smaller "pieces", which is doing what they do, decompose. Paphiopedilum is the plant I believe that there is more to the microbes, especially the fungi. It seems as if the plants grow more vigorously and mature faster with more of these Symbiotic fungi. It is still being researched, but I am almost sure that there are these microbes present in everyone's pot of Paphiopedilum. I do not think that the microbes enter the root cells of Paphiopedilum, but surround. Plants like Hexalectris, Corralhorhiza, and even Spiranthes depend on microbial fungi entering the tubers so the plant can live. The fungi die off, the plants ultimately dies off. Paphiopedilum, the surrounding microbes die off, the plant maybe dies off? I have never seen a pic of a very large specimen of Paphiopedilum in the wild, but have seen super large Cattleya and Schomburgkia, and even Dendrobium.

I am unsure if there is any research done on this, as I haven't looked around. I am trying to research on my own with no help to see what I can come up with. I still need lots more research, but I truly feel that the fertilizer does not directly affect the growth or development of orchids, and that the Paphiopedilum depend on Sybiotic fungi to survive. Selenipedium and Cypripedium are dependant on the microbes, not sure about Phragmipedium. Then there are always exceptions... I could be completely wrong on all of this, but I believe that my research is somewhat correct.

-P.A. Mahon
Mahon said:
Selenipedium and Cypripedium are dependant on the microbes

Got a source for that? I think it'd be hard to say anything at all about Selenipedium.

Sure, Cypripediums(as do all orchids) need a symbiotic fungi to progress beyond the seed stage, but I think it's hasty to say they are fully dependent upon fungi for adult survival. There have been reports of C. irapeanum(and C. molle and C. dickensonianum, presumably) needing its fungal symbiont for survival. However I don't think it's safe to come to that conclusion without any doubts.
I can only account for Selenipedium aequinactiale through a grower's research, which needs some type of Symbiotic fungi to survive. The plant also needs good drainage and aeration through the roots to live as well.

But what I originally posted is not based upon speculation (except for the developing research on fertilizer), if that is what is being get at. Though I am working under the "Birk" type of research, with no information sightings, I still am researching by experimentation.

I am almost sure that there are microbial fungi in rather small amounts in all cutivated plants of Paphiopedilum. I believe that if the microbial fungi popoluation increased, then the Paphiopedilum plant's growth would too increase. These have been my studies in cultivated Paphiopedilum species in my conditions. Perhaps the fungi may act different in other temperatures, in drier coniditions, or different microbial fungi found in different areas. The research is still being done, and I am going to be looking deeper at points that were discussed and posted.

Has anyone ever heard of Paphiopedilum species, in nature, growing elsewhere than dead logs, cliff sides, river banks, or in the ground? I know that Paph. malipoense is a lithophyte, but pictures of the plants show that there is accumulated humus or moss in the areas it grows.

-P.A. Mahon
I believe it has been documented that P. lowii has been found in tree croutches (sp?). There is often a bit of humus found there.

I grow all my multifloral with fine bark, perlite #4, sphagnum mixture of the top five inch of the pot. I use lava rock, perlite and gravel stone for the bottom half of the pot to provide good drainage. They grow real fast but I repot them 1 to 1.5 year.

I also have a Paph phillipinense that has been growing the the same pot for three years in a mixture of sponge rock #4 and sphagnum moss. The plant produced five flowers on its first blooming with two new growths.

I'd be most interested in knowing what people are using to pot their paphs in. Today I'm re-potting every one I have. Yes, even the ones that are blooming which I know is a big no no. I've used a mix from Kelly's Korner on some of the larger paphs and a paph & phrag blend from that has finer bark in it for some of the smaller paphs.

I've found a few threads, this one included, that do mention specific blends for paphs such as Paphman910 just above me but I'd like to hear from more people. Growing in 100% hydroton is out for me... too low of humidity in the house. I tried it an some of my plants were very unhappy even with me watering them at least once a day if not twice.

Also too, I believe there is something beneficial to paphs when microbial fungi is present in the mixes of cultivated plants as mentioned by Mahon. Does anyone out there add a few chips of the old potting medium in close to the roots when they re-pot their plants to capitalize on any microbial fungi that may be present?
We're coming into the holidays and then we're going to be leaving for a few vacations and I've got to toss DC in a few times throughout winter. Add kid stuff that is ongoing and I'm to my limits. Some of these mixes are breaking down and some of the plants I bought are totally rootbound. We're talking plants in bondage. I weighed the pros and cons and figured better now than next summer.

What is in that mix from Terry's at this Pine Ridge? Just curious.

By the way, can anyone tell me how to add an avatar. The very first paph I bought is blooming and that's the one I want for my avatar. It was my first.
Most of my mixes start out with Antecs basic CHC mix, but I may add oyster shell or chopped sphagnum depending on whether I think the plant would prefer a more basic or acidic mix.

Recently I've been moving my Barbata species (and a few other acid loving species) over to Lance Birk's "pretty good" mix. This is a simple bark mixture, but includes some sand for better drainage.

Overall I haven't found any mix that seems to be universal for all species or culture methods.
Overall I haven't found any mix that seems to be universal for all species or culture methods.
Basically, that's been my understanding which is why I'm sort of experimenting and poking around for what has worked for others. I truly don't have anything rare so if I lose one, I'll be upset but it won't be the end of the world.