Charcoal?

[ang709]

I've been looking at some commercial mediums for flasking, and I've noticed some mention specifically that they do or don't include charcoal. What are the pros and cons of having charcoal in the medium? What is it suppose to help with? Sorry, I'm very new to this aspect of orchids.

Also, if anyone wants to PM me the name of a specific medium you've had success with, that would be great too. Thanks!

[catttan]

In Malaysia our main potting medium is charcoal.Here our rainfall is around 100ins a year and it rains almost every late afternoon. We grow our orchids outdoors 24/7 in lathe houses for shade-loving orchids, or right out in the open with no shade for semi-terete and terete vandas,arachnis, aranda, mokaras. The high rainfall and temperature cause most conventional potting medium to rot and break down very quickly but charcoal remains intact for quite a long time. Moreover it remains 'sweet' over a much longer period of time. Sometimes we add broken bricks for better retention of water and also, if placed on top, to prevent excessive absorption of the sun's heat which might result in the burning of new emerging root-tips.

[delphiguy]

i think angie is asking for medium to use for flask.... i have no idea, i thought that flask
uses an agar or gel based medium. anyways if it was potting medium your asking i do
agree, charcoal is a nice medium to use for potting.

[Halloamey]

Angie, charcoal is added to tissue culture media as an adsorbent. Calli secrete some compounds that are inhibitory for their own growth when they accumulate in the media. The charcoal simply removes these wastes these from the media, so that the time between reflaskings can be increased. Another important function of charcoal is that it stimulates rooting, so it is added to media in which rooting of the plantlets is desired, usually the last flasking step. Earlier on only multiple shoot formation is desired and hence charcoal is skipped.

[catttan]

Sorry Angie for misunderstanding and thanks Amey for the info.Must read the posts more carefully next time.

[catttan]

A friend who does a lot of flasking informs me that he uses charcoal in his medium when he reflasks.He uses the charcoal pills he buys from pharmacies[the type we take for upset tummies] and crushes them to add to the medium. He also uses coconut water from young green coconuts in the medium.

[ang709]

Thank you, Amey, for the info, and thank you everyone else for the responses too. Yes, the medium is agar based, but one says it also contains charcoal.

[dawn_green]

As catttan said :
"the charcoal pills he buys from pharmacies[the type we take for upset tummies] and crushes them to add to the medium."

I guess its not charcoal.... but activated carbon....a norit maybe, and yes they are adsorbent, for unwanted gasses and liquids