Diatomite? Anyone know the benefit of this addition.

[Queenslander]

Anyone out there, know of any benefit in using this substance in the potting mix.? I was reading somewhere that it contains silica for the orchid roots? Your insight into this post would be appreciated. Thanks.

[King_of_orchid_growing:)]

There are a few posts about diatomite on here that you can pull up on the OB search engine.

But yes, it does contain silica because it is a sedimentary rock that was formed mostly from silica from the remains of fossil diatoms.

All plants utilize silica to some degree or another in one way or another.

The Chemical Nature of Silica in Plants.

There are other articles you can look for regarding silica and plants.

Not all orchids respond well to the use of diatomite because of its capacity to store high quantities of water due to its high porosity.

[tucker85]

I use a large diatomite as a medium for some of my Catts. They do well in it. I know one Cattleya grower who uses it exclusively. I don't think the silica makes any difference. I use it because it drains quickly and doesn't break down. On the negative side I understand that it tends to build up salts from the fertilizer. I flush the pots once a month to try and avoid that.