Potting medium for Phalaenopsis
 

I've been using sphagnum moss as the only medium for my phalaenopsis orchids, with a little charcoal at the bottom to elevate it. Unfortunately I find that when the monsoon season comes and it rains heavily (I live in the tropics), the sphagnum moss gets so wet the plant rots in the end.

Since the biggest problem I face is the orchid rotting from the bottom, I'm thinking of putting a porous medium like perlite at the base of the plant, which is then placed on a top layer of sphagnum moss. I'm not sure what to put in the bottom layer, maybe charcoal. Do you guys think this idea is good? I want the medium to be moist but not end up too damp during very wet weather.

I live in South Florida. I lost several phals because the roots stayed to wet.

I have been using bark mixture in a wooden basket lined with either screening material to keep it contained or pieces of the fiber from cocoanut tree branches. That way I don't have to worry about too much water. I've even taken an old tossed out phal and revived it in a basket. It bloomed for me as a thank you gift. Mine are all under cover and have to water yhem myself but the basket lets the excess to leave and air to move around to. Oh, the roots still manage to wind through the slats. Try one and see how it goes.

Lorraine

I'm not sure about using bark and fiber, I think I might overwater them, and with the many ants in my area I think if I use bark or fiber my pot will end up as an ant nest.

Other than wet weather, my phals normally end up dry, so I need a mix of medium to ensure they stay moist, but airy enough to prevent them from remaining wet.

I was also going to suggest bark. You can mix this up with sphag moss.
I cut up sphag in small pieces and add coarse rok (perlite) 50/50 mix. This mix stays fairly moist, dries evenly and does not compact overtime - drainage is excellent.

Sounds good, though I'm thinking of cutting down on the use of sphagnum moss, as it seems to me that the roots don't really grow down into the pot, any other recommendations for the bottom layer?

If you tend to overwater then definitely get them out of sphag. Bark will drain much quicker. Or you could do as Gloria suggests and do a bark sphag mix. If you are experiencing root rot then sphag is not working for you, it's working against you.

You can use styrofoam packing peanuts (the type of stryo they use to make hot cups from - this type shouldn't dissolve) I use those to line the bottom of my pots to keep any water from collecting. You can also use stones for drainage. The peanuts keep the pots light but if your plants are top heavy, the stones help to balance out the the plant's weight.

Sorry if this question sounds a bit stupid, but can you use spagnum for "adult" orchids like you use it for the tiny ones?

bye Agnes

I don't really like to use sphagnum now, but bark is not really a good alternative to me at the moment, as there are ants here which really like to make bark their home.

No not stupid at all, Rather a good question I think.
Absolutely, you can use sphag on larger grown plants aswell - They just like to dry out abit more then seedlings.

Have you seen the newer formulation of schultz mix? It seems much better then the older version, has larger chunks and more rock. The bark is larger in size but much less then it use to be.
Personally I don't care for bark anymore, just had too many problems with it.

You can also try crushed up lava rock, really good on the bottom of the pots.