FredL

Lesley, there are as many soil mixes as there are bonsai growers. I am using a mix of about 1/2 small lava rock, 1/3 mulch (any of the various bark based mulches will do) and 1/6 loam (garden soil with reasonable amounts of clay and loam included). The big thing is to make sure your mix will retain water within the granules that make it up but has space between the granules for oxygen. Which is to say, it drains rapidly (like gravel) but keeps a moist texture for some time (like mulch or clay). I personally think that small lava rock is the best "sand" component around because it is pretty "sharp" and has very irregular surfaces.

It seems like alot of people are going for mixes without soil in them these days, using some sort of calcined clay component rather than loam. The mixture I'm using is about the same that John Naka recommends in "Bonsai Techniques I". Some folks think it old fashioned, but it's inexpensive and I like it.

Fred