To Chc Or Not To Chc?

[Frederick]

The resident evil in CHC--let's be reasonable.

Many French growers are wary of Sanderianum's somewhat fuzzy "science" and "final" pronouncements.

I wholly support Rick's claim but that's only my personal opinion. In any case, there can be no mysterious physical or chemical reason why CHC should be "essentially" bad for orchids. If you buy it from a reputable source, if you wash it and treat it properly (see Antec's website), if you check its conductivity (give or take 60 microsiemens), if you mix it with a neutral cultural medium (e.g. charcoal, sponge-rock, etc.), if you check it regularly for ph, how on earth could it possibly become the evil thing some people imagine it to be ? Of course if you buy CHC with a salt contents which blocks your conductivity meter (this has happened to me) and use it straight out of the bag, problems shall occur but that's only fair.

It is also true that CHC will decompose in time depending on original quality, temperature, and humidity (2 years in my conditions). The CHC particles will form a kind of mud at the bottom of the pot with charcoal and sponge-rock particles--this is bad for the roots especially if you tend to overwater.

The same heated debate has been going on since the 19th C. Every single medium that works for you is THE ideal medium but it would be wrong to apply the same rules to all circumstances and all paphs (I suspect brachys dislike CHC but I don't grow any since they are all die on me).

You'll find that bark is equally difficult to apply to all cases. Bark pellets are lethal to my plants in my conditions and chunks are very difficult to find nowadays. I have never found a bark mix which works in my conditions.

I'd be very curious to know if anyone other than the interested party has ever used Lance Birk's "Pretty Good Mix" (8 parts medium grade fir bark, 2 parts chopped moss, 1 part 16 mesh silica or river sand). For obvious reasons a 16 mesh sifter is not available in France and I keep forgetting to buy one whenever I go to the States. I am sorely tempted to experiment with this mix. Feedback please ?

Happy growing
F.

 

[Roth]

Many French growers are wary of Sanderianum's somewhat fuzzy "science" and "final" pronouncements. .

Not quite. To put the records straight, the french growers are using my technics fot most of them, even if they sometimes forget to quote me as the originator. Initial quarantine, chemicals for disinfection, the high P fertilizers as plant starters, antibiotics for some of the, the potting mixes...

Prior to my advise to several people, that spreaded afterwards, only a few people could grow paphs in France, that`s a fact. Apart from Steph on rockwhool on orchideefantome, where he discovered an ideal way of using it, most of the `advise` that is passed nowadays in France comes from me.

It is not quite fuzzy science, anyway I do not matter too much about such statements, I am working now for a major pot-plant company, from that onwards...

In any case, there can be no mysterious physical or chemical reason why CHC should be "essentially" bad for orchids.

You are wrong on that. There are chemicals reasons, but they are not related to salt concentration at all. There are ome lectins that are phytotoxic, and some other compounds, some of them are just detected but not analyzed fully. For the physical reasons, it is a very strong cation binder, and yes, if we remove this ability the things are doing better.

I was thinking of releasing as a scientifical paper the complete coconut-related problems, but now prior to that, I will take a patent on how to process it correctly. Free for hobbysts, but for sale for commercial people. It seems only fair to me.

Thinking well, if I did patent the use of calcium nitrate and magnesium sulfate to release the sequestrated sodium and potassium, I would be very, very wealthy... So now, I will patent the part II, to make CHC really an ideal product.

If you buy it from a reputable source, if you wash it and treat it properly (see Antec's website), if you check its conductivity (give or take 60 microsiemens), if you mix it with a neutral cultural medium (e.g. charcoal, sponge-rock, etc.), if you check it regularly for ph, how on earth could it possibly become the evil thing some people imagine it to be ?

Hormons at first, and second, salt release. Third, some batches are derived from greem coconut, and they have a very organic content, which eventually will be a perfect substrate for fungus and bacterias. Fourth, some batches are contaminated with pseudomonas and/or fusarium.

Last problem is instability of the media and total inconsistency in the batches. There are some aside problems with some phytotoxic lectins too...

When I did a major expert work for the french customs, we shortly realized that all the exporters that sold coconut products to France were major scammers. All shipments to France, without any exceptions, had forged documents, fake statements, etc... Some were imported as ` pillow fillers`, some as ecologic additives to concrete - enjoying tax free import, some had fake analysis... None were in fact acceptable for a reason or another. 1 container would have many types of products and qualities, and the `dessalted one` still had some thousands ppm of sodium bound to the fibers. As explained many times, this part of sodium and potassium is bound, and does not ionize in water, therefore a EC check would not detect anything special.

Of course if you buy CHC with a salt contents which blocks your conductivity meter (this has happened to me) and use it straight out of the bag, problems shall occur but that's only fair.

Not only, a major part of the monovalent cations are captured by the CHC, even with 10 rinses in pure water and a final EC of 0, problems will happen.

I suspect brachys dislike CHC but I don't grow any since they are all die on me.

In fact, they love it if you keep it evenly moist

You'll find that bark is equally difficult to apply to all cases. Bark pellets are lethal to my plants in my conditions and chunks are very difficult to find nowadays. I have never found a bark mix which works in my conditions.

I put somewhere on a forum the way to process bark, the main problem in France is that most of the good quality bark is presold to the Netherlands, second it has to be pretreated to be used, and third, there are many types of pine bark... Last, bark is better when mixed with something to retain water in a different way - not droplets type- such as coconut, sphagnum, peat or otherwise

I'd be very curious to know if anyone other than the interested party has ever used Lance Birk's "Pretty Good Mix" (8 parts medium grade fir bark, 2 parts chopped moss, 1 part 16 mesh silica or river sand). For obvious reasons a 16 mesh sifter is not available in France and I keep forgetting to buy one whenever I go to the States. I am sorely tempted to experiment with this mix. Feedback please ?

I am trying actually as a way to reduce costs locally. I found out so far after 3 months that moss is far superior for barbata to sphagnum in paphs potting mix.

For the 16 mesh you do not care to get it from the US, it is the french 1.2mm sieve, you can get one at many places in Paris, close to the universities, geology students use it very frequently.

 

[Ray]

I think it is impractical to equate terrestrial plant performance with powdered coir with orchid performance in husk chips. I'm not saying that there may not be a correlation, but reactive surface area plays a huge role.

One can easily grow orchids on marble gravel, but if you try to use it in a 'sand" particle size, the pH will knock out the plants in no time!

 

[Rick]

I found out so far after 3 months that moss is far superior for barbata to sphagnum in paphs potting mix.

For the 16 mesh you do not care to get it from the US, it is the french 1.2mm sieve, you can get one at many places in Paris, close to the universities, geology students use it very frequently.

Do you mean peat moss versus long leaf sphagnum moss? I thought both are sphagnum, but peat is aged and shredded versus fresher and whole for long leaf.

 

[Rick]

Moer CHC carnage.

I thought I'd repot a baby supardii I got from Fox Valley in 4/05. I think it was about 6-8 inches at the time and in bark. I repotted in my chc mix and haven't repotted since, but added some oyster shell on top from time to time.



Its a bit over 18" across now, and I think the roots look pretty good.

 

[SlipperFan]

They look great!

 

[davidvaldez33]

WOW! I never thought I would get this much debate and input from my question! Thank you all so much! I have since repotted all of my paphs into a fir bark mix in clear pots. I have seen a lot of new root growth on some of my plants and the roots have root hairs! They never did in my chc mix. My plants have always had pretty strong growth in chc, but I was always worried about the roots. In Ricks post of his supardii, It looks like he is having the same problem that I had. I might be wrong, but I think that the long roots in his pics are the original ones that the plant had when he purchased it in the bark mix. If you look closely at the bottom pic you can see that they the ling roots have root hairs. Right above these roots you can see a multitude of very short dark roots that no longer have active growing tips. I think that these are the roots that tried to grow in the chc after the initial repotting. Above those, there are some new roots starting that still have active root tips, but I think these too will stop growing soon and their active tips will die also. I had this same problem also and this was the reason I originally posted my question. I do not know why, but the top growth seems to do nicely, but root growth is stunted.

 

[Rick]

I might be wrong, but I think that the long roots in his pics are the original ones that the plant had when he purchased it in the bark mix. If you look closely at the bottom pic you can see that they the ling roots have root hairs. Right above these roots you can see a multitude of very short dark roots that no longer have active growing tips. I think that these are the roots that tried to grow in the chc after the initial repotting. Above those, there are some new roots starting that still have active root tips, but I think these too will stop growing soon and their active tips will die also.

Afraid you do have it wrong. Keep in mind this plant has tripled in size in 3 years while potted in the same batch of chc. That's a tough feat for a plant with dead roots. Also the original roots on the seedling (typical of young plants)were thin and wiry. The hairy roots in the photo are less than 3 years old, and some of the pieces of the original roots are the black things with no tips. Typically my multis do not grow roots during winter, and will not have active growth tips until late spring - summer. Then they go wild. Those new roots should have no problems with the CHC this year either. I have 4 sanderianum, and 4 stoneis, all in CHC and most in clear pots, and there is lots of active root growth going on now. I just repotted my kolo (which went from a single growth 18" plant to 7 growths up to 28") which has been in the same CHC mix for 4 years, and its roots had packed the pot.

I have other species potted up in bark mixes too for different reasons, but I think I'm getting good to superior results with my multis without the annual repotting hassel of standard bark mixes.

 

[Rick]

Supardii update

Here's a couple of pics of my supardii that got repotted in the PO4 enchanced CHC mix. Those aerial in the previous post that were supposed to turn black and die seem to have done quite well, and the plant has started 2 new growths. I think its on schedule to bloom this spring.



The stonei I pictured on the previous page also went crazy after repotting and the sheath is starting to thicken with spike. Also those wardii seedlings from Gilda's post were potted up in a CHC sphagnum mix that seemed to work well for those guys.