:?: I've heard that some growers in Germany are using a growing medium called Turface. Does anyone know anything about this product or have used it? A google search shows that it is a clay product often used in bonsai, among other things.

I have a bud who does bonsai and he's familiar with it. I think our golf course construction division also uses it in building greens or tees. I see that Roberts Flower Supply carries it and it's recommended as a potting medium component for Cypripediums so I may get some. He's at orchidmix.com and the price is $0.45/lb. or 50# bag $15.95

I've also wondered if I couldn't just pound up and sift into different grades the excess Hydroton I've got sitting around.

From what I can see on the web it "sounds" a lot like a local product called Oxycinty which I use. The web says Turface is "a crumbled porous ceramic product". If it is like Oxycinty then;

I purchased some about three months ago and moved some Dendrobes and Cats to it - They're powering along quite well. I've also used it as a S/H and potting medium for some Paphs and two Phrags with mixed results at this time. Two of my plants were recently "broiled" alive after I left them be exposed to the Sun at the wrong time of day. The product wicks quite well with the upper layer remaining alarmingly dry. A layer of Sphag (for those plants that can cope) will allay fears on that front.

My best result using Semi Hydro to date though is Hydroton and a Phrag Praying Mantis. It's only been in the container about two months and I can see root progress on a daily basis.

Cheers
Stephan