In 1994 I started to be interested in the then "new" coconut products, namely coconut coir and coconut chips (CHC).

First problem was to find suitable suppliers. In those ancient times, coconut products were harvested from old stocks in public garbage areas in Sri Lanka, as well as from new materials. The former was of very dark brown blackish color, the latter tan-colored.

The former initially promoted good root growth of certain species, its EC was in the 100µS and under, but it was decaying very quickly, under a year most of the time. An enormous amount of dust and fine particles preventer proper drainage. The material processed from new coconut products was much better in terms of structure, but the EC of batches varied between 300µS 1:1.5 water extract and 5000 µS 1:1.5 extract. Proper washing with deionized water helped to bring down EC to acceptable level. Yet, either coir or cocochips promoted a general chlorosis with yellowing, leaf tip browning, especially in older leaves. A normal Paphiopedilum plant has a foliar analysis content of 1.3K, those grown in the CHC or coir processed with RO water only had only 0.7 K, BUT up to 0.5-0.8 Na ( sodium). There was clearly a big problem.

After investing some consequent money in 1997, I discovered that the CHC had a content of up to 800 ppm Na even when washed with pure water many times. By discussing with a large soil-manufacturer, he told me that Calcium nitrate and magnesium sulfate soaking was required, for about 10 days to 2 weeks, because the sodium and potassium ions present after the RO washing were impossible to remove with pure water.

Only an exchange with divalent ions ( Ca++ and Mg++ ) would remove them. Soaking with 8 g/L Ca(NO3)2 ( calcium nitrate) followed by a soak in 4 g/L MgSO4, 7H2O (Magnesium sulfate) would remove those ions. The EC of the resulting product would then be brought down to 400 µS with a water-calcium nitrate solution, and the product would be ready to use. He warned me that some stocks are heavily contaminated by phytium, as it is evident by some problems encountered by a carnivorous grower using this mix, and contaminated by fusarium in some others instances. The former would promote black roots and a general chlorosis of the plant, followed by its death, the latter a more chronic illness, with healthy roots growing along rotting ones, and general chlorosis, dwarfing, sometimes a lot of tiny growths appearing at the base of the plant, swollen stem... All of those symptoms due to hormones excreted by the fusarium. Both fungus have been identified in substrate and plants grown in by a major lab using PCR technics. The sodium and potassium load that could not be washed have been found by a destructive analysis using the latest tools available ( plasma analyzer). Baryum sulfate is a second choice to perform this analysis.

I then published on the AOS forum the results, many people have been incredulous, but this way of washing coconut products seems to be the norm, and some articles have been published afterwards mentioning this problem. Nowadays, had I not insisted on the AOS forum, it would never have appeared anywhere, and plants would still be slowly dying in coconut products around US.

Two notes :

- No supplier apart from those getting the Dutch RHP label has its coconut products properly washed straight from Sri Lanka.

- Standard Calcium nitrate/ CalMag fertilizer irrigation is far from being enough to wash it over time. It would require several years. People who did not see any symptoms may have their fertilizer program on the high end. If the plant is deficient in anything, it will start to pump sodium from the CHC ( yes plant roots can dissolve the sodium contained in the CHC !), become chlorotic, and there is nothing that can be done to bring it bak on the healthy side.

Thank you very much for that post. I followed the current thoughts in washing CHC using calcium nitrate and epsom salts with three soakings using DI RO water. I checked the TDS level after the final soaking and everything appeared alright. The paphs grew and rooted very well for the first 6 to 8 months and then I noticed a distinct lack of live root tips. I repotted everything into fir bark ( only the bark that floats ) and aliflor and the improvement in the health of my plants is quite dramatic. A number of individuals at the WOC in Dijon mentioned that they tried CHC and gave up after noticing a deterrioration in their plants.

Thank you very much for that post. I followed the current thoughts in washing CHC using calcium nitrate and epsom salts with three soakings using DI RO water. I checked the TDS level after the final soaking and everything appeared alright. The paphs grew and rooted very well for the first 6 to 8 months and then I noticed a distinct lack of live root tips. I repotted everything into fir bark ( only the bark that floats ) and aliflor and the improvement in the health of my plants is quite dramatic. A number of individuals at the WOC in Dijon mentioned that they tried CHC and gave up after noticing a deterrioration in their plants.

The process is very complicated; no matter what is published by some people. One of the promoters of its use even advertized several plant ( a Dollgoldi, and an Hookerae), claiming that the plants were repotted in fir bark aliflor and something else, but not coconut. Cocochips are excellent if you are willing to process it with the high rate of calcium nitrate and magnesium sulfate, wash it with the calcium nitrate solution... Count at least 8 washings all included.

Then... you must solve peculiar requirements regarding micronutrients. No commercial fertilizer do that, so you have to make it up by yourself. Finished ? Not yet ! Foliar analysis are required to ensure that the levels of nutrients are good enough. Usually there is a lack of some in plants produced in CHC/coir, and after a while the plants bleaches, no more root tips, and the plant is gone.

About the people who mentionned their problem to you, do you know in which country did they reside ? Some countries have got extremely poor quality CHC as well, such as the one sold by several french companies.

There were a number of individuals who mentioned that they no longer use CHC at the WOC. One was a grower in Southern Florida and another was an AOS judge from California. It was very interesting to finally talk to other growers who were experiencing the same problems in CHC as I was having. Up until that point everyone seemed to be thinking that CHC media was an improvement over bark mixes. I live in the U.K. and had imported my CHC from a U.S. source as I could not locate any good quality CHC locally.
I have a large collection of paphs (in the 1000's) and it was interesting that some plants were much more affected by the CHC than others. I imagine eventually they all would have started to go downhill.

I do have a few awarded divisions (paphs), that are still not doing well after repotting into bark approximately three months ago. Is there anything you could recommend to improve their chance of survival?

Thanks

There were a number of individuals who mentioned that they no longer use CHC at the WOC. One was a grower in Southern Florida and another was an AOS judge from California. It was very interesting to finally talk to other growers who were experiencing the same problems in CHC as I was having. Up until that point everyone seemed to be thinking that CHC media was an improvement over bark mixes. I live in the U.K. and had imported my CHC from a U.S. source as I could not locate any good quality CHC locally.
I have a large collection of paphs (in the 1000's) and it was interesting that some plants were much more affected by the CHC than others. I imagine eventually they all would have started to go downhill.

I do have a few awarded divisions (paphs), that are still not doing well after repotting into bark approximately three months ago. Is there anything you could recommend to improve their chance of survival?

Thanks

Unfortunately nothing. I faced the same problem, and the plants eventually died. You may try a very harsh fungicide soak such as thiophanate-methyl + Subdue soak overnight, as sometimes the problems are related to fungus invading the roots from the cocochips ( and the affected roots do not show any symptoms...), but most of my experience has been to send them to the garbage can, that's the place they eventually end up after a while. I guess your plants are yellow and white colored by now, or the leaves look "dehydrated" even if they are not ?

Some others oddities were a pot full of roots and no leaf anymore...

Actually, I warned everyone as soon as I could 3 years ago about the dangers of coconut products... on the OrchidWeb forum. It can be used, I still use it, but it is first time consuming, and second you must have an excellent lab to follow you at any time.

Hmm, interesting information, thanks for sharing it.
Makes me nervous.

Never heard this before... I'm more worried about the fungi than the salt, quite frankly. Especially since I fertilize continuously... Would a bleach soak of coconut, followed by a rinse or two, be sufficient to kill the nasties? I'm not autoclaving it, and I just bought ten bales...

I have heard that there are several sources of coconut, and the best is from coconuts harvested from fresh water areas, not near the seacoast. Presumably this gives you a lower salt load. I've heard varying descriptions of which location is better, usually I'm told that the Sri Lankan is the best.

Never heard this before... I'm more worried about the fungi than the salt, quite frankly. Especially since I fertilize continuously... Would a bleach soak of coconut, followed by a rinse or two, be sufficient to kill the nasties? I'm not autoclaving it, and I just bought ten bales...

I have heard that there are several sources of coconut, and the best is from coconuts harvested from fresh water areas, not near the seacoast. Presumably this gives you a lower salt load. I've heard varying descriptions of which location is better, usually I'm told that the Sri Lankan is the best.

No, because if you are using fertilizert continuously you will have heavy problems after a while... coconut accumulates some ions, to be released all at once later, to phytotoxic levels, bleach soak will in fact weakens the coconut

Never heard this before... I'm more worried about the fungi than the salt, quite frankly. Especially since I fertilize continuously... Would a bleach soak of coconut, followed by a rinse or two, be sufficient to kill the nasties? I'm not autoclaving it, and I just bought ten bales...

I have heard that there are several sources of coconut, and the best is from coconuts harvested from fresh water areas, not near the seacoast. Presumably this gives you a lower salt load. I've heard varying descriptions of which location is better, usually I'm told that the Sri Lankan is the best.

No, because if you are using fertilizert continuously you will have heavy problems after a while... coconut accumulates some ions, to be released all at once later, to phytotoxic levels, bleach soak will in fact weakens the coconut

Hmmm. Well, it is something to think about. I have been starting to move away from my usual coconut mix for paphs and phrags (2:1:1 medium coconut, #3 charcoal, and similar perlite). My main beef is that it was staying too dry. I did lose some plants to symptoms similar to what you describe (chlorosis, dessication, etc), but I was attributing that to dryness. Plants kept wet (in a variety of ways), or in larger pots (6" or greater) are all fine. It could be that constant moisture keeps salts from precipitating out back into the coconut husk. Or it could be something else. I was planning on switching to a smaller grade coco chip for slippers, to increase moisture retention. For cattleyas and the like, the coconut mix has been very good, I have yet to see a problem with it.

My long term goal is to get away from coconut and bark entirely. I'd really like to grow in an entirely rock based mix, for most things, and a 'mud' type mix for everything else. That is partly due to ease of repotting (or lack of repotting, in rock), and partly because I have serious concerns about the quality of bark I've been seeing. Now you go and ruin my backup coconut on me... Sheesh.

I haven't had as much luck with the 'semihydropics' as I would like, but I'm experimenting with some blends of different things (LECA and diatomite, lava rock, shredded tires... you name it). I might try some blends with rock wool.

Hmmm. Well, it is something to think about. I have been starting to move away from my usual coconut mix for paphs and phrags (2:1:1 medium coconut, #3 charcoal, and similar perlite). My main beef is that it was staying too dry. I did lose some plants to symptoms similar to what you describe (chlorosis, dessication, etc), but I was attributing that to dryness. Plants kept wet (in a variety of ways), or in larger pots (6" or greater) are all fine. It could be that constant moisture keeps salts from precipitating out back into the coconut husk. Or it could be something else. I was planning on switching to a smaller grade coco chip for slippers, to increase moisture retention. For cattleyas and the like, the coconut mix has been very good, I have yet to see a problem with it.

My long term goal is to get away from coconut and bark entirely. I'd really like to grow in an entirely rock based mix, for most things, and a 'mud' type mix for everything else. That is partly due to ease of repotting (or lack of repotting, in rock), and partly because I have serious concerns about the quality of bark I've been seeing. Now you go and ruin my backup coconut on me... Sheesh.

I haven't had as much luck with the 'semihydropics' as I would like, but I'm experimenting with some blends of different things (LECA and diatomite, lava rock, shredded tires... you name it). I might try some blends with rock wool.

Actually I grow my plants nearly dry, compost varies from a bit wet to "on the dry side". You can use Canna Coco A+B at very low rates, around 200µS if you do not want to bother with a sophisticated formulation.

One formulation that is average is there:

http://www.cocopeat.com.au/technical/hydroponics/reports/liquidFeedForRoses.asp

You must adjust the macronutrients to 300mg/L, not more, and use micronutrients full strenght. Get analysis performed of your running water to watch for the increase in B, Fe and Zn that occurs after a while... and adjust the micronutrients levels accordingly.

It is too long to explain, but if a substrate retains 1L of water for 5 L of substrate :
- If you water it with a 1g/L fertilizer solution, after a while, when 900mL of water will have evaporated from the pot, not taking plant transpiration into account, the result would be the same as watering with a 100mL solution of a 10g/L fertilizer.

Figures of 100ppm N to start with are way too high to care properly for paphs in many substrates, if you let them dry out between watering, which is the way to do in cocoproducts.

Can you address Antec's use of CHC for 4+ years without any apparent problems?

http://ladyslipper.com/coco3.htm

Can you address Antec's use of CHC for 4+ years without any apparent problems?

http://ladyslipper.com/coco3.htm

Yes, they recommended on Ebay a mix of bark + perlite for Paph hookerae, and on their shop, there were quite a few community pots comporting a fair amount of stunted seedlings as well. It is not accessible yet, but it is very, very obvious.

Thanks, Papuanum. I just made some divisions last night. Maybe two can make in bark as a control over the next 2 years.

Papuanum, what do you recommend as a media for Paphs?

So is CHC the same as the blocks of stuff they call "Coco peat"?

It comes in big blocks that you soak to break up and then mix it with perlite.

Just wondering if this is the same thing.