Using activated charcoal for orchid medium

[newflasker]

Hi RoyalOrchids,
We come here to share information and to learn from each others. Moreover, we want to talk/chat with others for fun. There’s nothing to be too serious, smile. Right or wrong it’s doesn’t matter. Fun is important. What a coincident!!! Today in plant tissue culture forum Dr. Arditti , Aeron Hicks and some people discuss about the AC and phenolic exudation problems in Phal stem and plant propagation. It’s funny that what Dr. Arditti said is not what somebody said he is. Cheers.

[Royal]

Yeah, I'm on that listserv too. I just knid of lurk in the shadows, taking in all that good info from some of the real pros like AJ and Dr. Arditi.

I didn't mean to come off too harshly. Sometimes I just get typin' and my trying to be clear and concise comes off as wordy and snooty. My bad!

You're right about the fun here! Sometimes the TC listserv gets a little .

[Louis_C]

Originally Posted by newflasker

Hi RoyalOrchids,
The correct term is adsorption which means binding particles/molecules to the surface but many people use absorption for easy to understand. It doesn't matter as long as we have an idea that some how absorber takes/traps/captures the chemical.

Activate Charcoal (or Carbon) AC is made form charcoal. Charcoal is heat at high temperature to create a porous structure which have extremely large area that can adsorb organic chemical. In tissue culture and orchid propagation, AC is preferred because it's not only darkening the media but it also adsorbs acid (old media get low pH), phenolic and unwanted organic chemical in media. There are many articles about using AC in orchid propagation. I talk to many people who use AC and they like it. However, AC powder is too expensive and not sold for a small quantity (Phytotech only sells 500g or more I believe). One time, I try to grind AC of my water filter (AC of water filter is good): It's too hard and it takes a long long time to get real fine powder so I stop doing it. It's much easy to do it with horticulture charcoal (HC) because it's soft. I tried HC and don't see much different so I ask your guys to see you try it or not. Some people talk about AC in media (not in vitro media) so the question get lost. There no doubt about charcoal in substrate is good but in vitro is good or not? Try it RoyalOrchids and let us know. Cheers

Do u think complete natural BBQ charcoal might work well?

[SADE2020]

Originally Posted by newflasker

Hi RoyalOrchids,
We come here to share information and to learn from each others. Moreover, we want to talk/chat with others for fun. There’s nothing to be too serious, smile. Right or wrong it’s doesn’t matter. Fun is important. What a coincident!!! Today in plant tissue culture forum Dr. Arditti , Aeron Hicks and some people discuss about the AC and phenolic exudation problems in Phal stem and plant propagation. It’s funny that what Dr. Arditti said is not what somebody said he is. Cheers.

I want to know if active charcole does well or not, within the potting mix or just as a filter sorce in the terrarium

[Ray]

I would not recommend it for incorporation in an orchid potting medium.

When used as aquarium filtration, the charcoal functions as intended, removing contaminants from the surrounding environment, holding them by adsorption, so they are not left in contact with the supported life in the water.

The same thing happens in potting media, except as those contaminants sit there and dry out, the deposits become greater and greater, and since they are still in the immediate environment of the root system, become pockets of toxicity.

Horticultural charcoal only has a minor level of activation, so contaminants it may trap can be more easily washed out of the pot. It’s use in media is primarily due to the fact that it rots more slowly than other components , not to purify the medium.

[K-Sci]

Originally Posted by Ray

I would not recommend it for incorporation in an orchid potting medium.

...

Horticultural charcoal only has a minor level of activation, so contaminants it may trap can be more easily washed out of the pot. It’s use in media is primarily due to the fact that it rots more slowly than other components , not to purify the medium.

Adding to what Ray said, activated carbon is heat treated and may also be chemically treated to increase its effectiveness adsorbing specific target 'impurities' depending on the intended use. 'Impurities' makes it sound as if only bad stuff is being adsorbed, but this isn't necessarily the case.

- In an orchid flask or potting media essential micronutrients might also be removed. How could you know? Failure to thrive.

- Because the intended use differs between products, one person's experience can be different from another's.

- Activated carbon may release impurities it has trapped under unspecified circumstances. Drying out, changing pH, introduction of a new chemical. How can you know? Not easily. There are a lot of variables.

[Shadeflower]

I think the original question was intended mainly for activated charcoal in flaskling media.
The question was whether it improves root growth or whether it inhibits growth more.

I think we canconclude it does not inhibit growth. Sure we can blame the AC if something goes wrong but then why does it work for thousands that do use it?

Does it actually improve root growth? Highly unlikely since that is not why it is added.

It is added for the same reason it is added to fish filtration systems. To theoretically trap impurities that could foul the water.

It would not absorb any more nutrients than a piece of bark would and to me the argument that it might absorb beneficial nutrients is not something I would ever worry about just like I would not worry about bark absorbing nutrients either.

What I was interested in recently was why sugar was added and it seems sugar can act like a plant growth hormone so you can grow seedlings without sugar, you can grow it with some sugar but too much sugar starts to cause deformed growth and higher mortality in seedlings. The correct ratio seems to be 10g/l

What is vitally important to this is if you start making your own seedling mix. I saw one recipe online mix 200g banana, 200g tomato, 200g coconut and 10g/l sugar.

That is way too much sugar as one has to realize fruit contains fruit sugar. Quite a lot actually. That is why a banana seedling mix works well. But people ignore the sugar content in banana and just add more sugar (a plant gorwing hormone) to the mix.

This results in reduced growth after about 5 months apparently. I am just quoting what I have learnt so far as I am just gathering information which is readily available online. One article I found was very helpful understanding what all the ingredients do and if gibberelic acid is good or bad to add:

(PDF) Techniques and applications of in vitro orchid seed germination

[katsucats]

On sugar... of course you could grow orchids in any kind of fertile medium. But the whole point of getting it out of the agar in the first place is that agar attracts other pathogens if it is not kept clean. And so replacing it with some other nutrient medium kind of defeats the point, wouldn't it? You might as well keep it in the agar and move it to seedling trays with the agar.

As for absorbing nutrients, I'm sure all medium absorbs some nutrients. And then the nutrients precipitate to the surface and form salts. For example, how do we observe salts on the tops of dry LECA if the LECA doesn't absorb nutrients from the reservoir, then pass it up somehow?

As for releasing impurities, all those "impurities" must have existed in your medium in the first place to be trapped. Trapping is a chemical reaction with carbon. At some point the molecular sites are filled, and additional impurities are not absorbed. But that doesn't mean the charcoal suddenly dumps everything it absorbs at once (and I doubt that it could be "washed out" once chemically bonded, unless you use acetone or something, kidding of course).

[Shadeflower]

Katsukas,
sorry but I didn't understand a word you said there.
Is it me?
It is far too early. seedling media is made out of water, sugar, agar, vitamins, minerals and nutrients.
It is a great media that seedlings can stay in for years with no watering. It is a bit of a miracle breakthrough in easy seedling watering tbh.
There is no urgency to remove seedings from this mix as you put it. Only if the mix goes off.

Now I had a think about any fruit I would pick and probably the last candidate I would pick is banana when it comes to picking something that won't go off. Think how easily a banana goes brown. It start rotting the moment you buy it. Literally a bruise makes a banana go brown.
So if you use banana in your seed mix, you open your container - goodbye seedlings - unless like Kat says you have to rescue them.

But like Kat I know I have far too little experience to know the benefits or not of sugar, honey, banana, cocnut water - why does nobody use orange juice? Is it too acidic? So I won't claim to but I just had to point out there is no point trying to make a point when like me you have too little experience to do so. I'm trying to gather information to help me.

[Ray]

Originally Posted by Shadeflower

Katsukas,
sorry but I didn't understand a word you said there.
Is it me?
It is far too early. seedling media is made out of water, sugar, agar, vitamins, minerals and nutrients.
It is a great media that seedlings can stay in for years with no watering. It is a bit of a miracle breakthrough in easy seedling watering tbh.
There is no urgency to remove seedings from this mix as you put it. Only if the mix goes off.

Now I had a think about any fruit I would pick and probably the last candidate I would pick is banana when it comes to picking something that won't go off. Think how easily a banana goes brown. It start rotting the moment you buy it. Literally a bruise makes a banana go brown.
So if you use banana in your seed mix, you open your container - goodbye seedlings - unless like Kat says you have to rescue them.

But like Kat I know I have far too little experience to know the benefits or not of sugar, honey, banana, cocnut water - why does nobody use orange juice? Is it too acidic? So I won't claim to but I just had to point out there is no point trying to make a point when like me you have too little experience to do so. I'm trying to gather information to help me.

You're probably right about the orange juice being too acidic. I know folks have done a lot of experimentation trying to find the "right" substrate for germinating seed, and then another for the replate flasks, and apparently they can vary genus to genus.

The nutrient content of the agar is limited, so eventually, the seedlings will starve to death if not replated or removed from the agar.

Back to the thread subject for a moment, my understanding about the activated charcoal use in agar is that it traps the phenols the plants secrete as a means of limiting competition, allowing more of the seedlings to survive.