You might try milled sphagnum as a medium also. I had good success with that. Peat/sand works for a lot of people well, but I have figured out that it does not work for me, as the silica sand I get is pretty fine, and I believe it compacts the soil too much. Tamlin's method of having the water table high may help a lot also.
Cheers,
Joe
Cheers,
Joe