Question: Charcoal in potting mix for neps

[alpiner]

To all neps guru,
To increase media airiness for neps, I'm thinking of adding charcoal as one of components. Question is, what's the good size for charcoal bits (or not important) and relative quantity do you use in the mixture? Do you hv good recipee for bottom part of the pot?
I'm unsure whether I shd stick to perlite+sphagnum moss(~1:1) for bottom, and top 1" with pure dried sphagnum moss. Or add charcoal with SM, or charcoal/perlite/sm, ... Is it advisable to use charcoal for orchid, soaked overnight? Those are normally quite chunky. Of course, with brute force I can smash them left right center.
Materials that are readily available to me: SM, coco peat, perlite, charcoal. Your advice is very much appreciated. Thx in advance.

[paphioboy]

Depends on what neps you are using them for. If veitchii and other epiphytes, I use charcoal (~1cm) + coarse burnt earth + limestone. Same mix for northiana. Charcoal is supposed to be beneficial in the mix, but I think it also can cause your media to be unevenly wet, as it obviously does not absorb as much water as sphag. I think it is good as crocking; place a layer at the bottom of the pot just so that when the moss ages and starts to compact, it does not cause anaerobic conditions which may lead to roots rotting. My 2 sen...

[edwardyeeks]

Keep ur charcoal bits around 1cm in diameter. I smash mine to smaller bits, big chunks can disrupt the flow of water and aren't too beneficial for the roots. Charcoal works really well on neps that need good airflow, but I doubt it's good with the neps that reside in the swamp, like bical and amp. Works really well with my northiana.

[alpiner]

paphioboy, edward,
Thx for your guidance. I'll definitely smash my charcoal to small pieces in future. Do you think adding perlite to charcoal+SM at bottom will help? I don't hv other materials, as listed in my first post. Of course, I've coco peat, but personally I don't think mixing it will increase airflow.
How about hybrid btw HL and swamp neps? Does it follow father/mother side, or mostly follow LL condition?

[edwardyeeks]

Using charcoal on most neps is ok, but if you mix charcoal with fine media like cocopeat or unwashed burnt earth, be prepared for the fine media to "go through" the larger charcoal pieces. Charcoal is good for neutralizing chlorine, otherwise, it's a neutral media that helps improve airflow. Perlite is fine, but bear in mind that perlite absorbs water while charcoal does not.

[sooxiwei]

I do not have good experience using combo of charcoal with shpagnum moss as I loss some VIP plants to it including my Campanulata...

if you were to compare charcoal to the traditionally used perlite:
-Perlite float easily when you water, causing a mess over time if you mix it with medium like sphagnum moss while charcoal won't
-Size wise, charcoal is more flexible as they come in all sizes while perlite proves too fine for bottom filling(flow of a lot after watering if the bottom of the pot does not touch the ground)
-Perlite absorb water while charcoal don't, but stack up charcoal tends to provide space that keep water from totally flush off, where by those part that expose to air near the surface will dry off faster while those in the middle will still remain wet
-I've seen charcoal in humid condition, white mold/fungus is spotted on those that are on the surface(samething will happens to smashed bricks, with extra cheese smell) when mix with sphagnum moss, not sure if it harms or not, but so far my albomarginata "Cameroon Highland" cutting still yet to settle in it after 2 months

[paphioboy]

I have used cocopeat +crushed charcoal before. Works well on the more common things like ventrata, raff, Miranda etc. I do not have the exact composition but I guess about 70% cocopeat to 30% charcoal. You can add perlite if you wish. Personally, I do not use perlite as I find it doesn't really do much...

[edwardyeeks]

My potting mix is sphagnum peat moss, burnt earth and a little perlite. Plan to replace perlite with charcoal.

[sooxiwei]

Originally Posted by edwardyeeks

My potting mix is sphagnum peat moss, burnt earth and a little perlite. Plan to replace perlite with charcoal.

the problem with perlite is that it is light and float once you water, find it very troublesome, but then for cp like cephalotus that is more sensitive, I still go for perlite as it is proven instead of take a big risk with charcoal unless I got lot of extra plant later on

[alpiner]

All,
Thx for your responses.
From what I gathered, I'm planning to put ~2-3cm of crushed charcoal as bottom layer for airiness, mixture of perlite+sm in btw, and top 2-3cm pure sm. Maybe btw charcoal and perlite/sm, I'll add transition layer of charcoal/perlite/sm. Do you see any problem with this setup? If it's working, I'll adjust layer thickness for diff nep type, e.g. if swamp neps then thicker perlite+sm layer, HL then thicker charcoal layer.