If you're purchasing it already packaged for bonsai, you'll pay through the nose. If it is still in its original bag (40-50#) it will be more reasonable.

Yep, I became aquainted with Turface around twenty five years ago while attending conferences and industry shows relating to the golf course industry as a consultant. Turface is first and foremost an amendment or construction material for sports fields.

I started adding it to my potting mix after that. My first bonsai mixes didn't remotely resemble what it is today and I really don't know when it became popular for that use. Quite a long time, I expect. I've pretty much lost my infatuation with Turface at this point but know where it can be purchased locally.

Alot of people use the oil absorbing clays also. From what Ive read, its the same thing but way cheaper and easier to find.

It was a 50lb bag for something like $25.00. I've sifted half of it and will use it in the 1:1:1 gritty mix for my Meyer lemon. First time I've had or transplanted a lemon. Wish me luck.