Questions about akadama

[Joe Dupre']

I have no doubt that akadama has worked for many people all over the world. I'll probably never use it because of the expense and the fact that my soil does everything I ask of it. For the people that use it, does the fact that is seems to break down into smaller and smaller particles affect the water holding ability? I mean, less space between particles normally means a denser medium that, I would think, holds water longer. Has anyone noticed this?

Another thing. If it does hold water longer because of it's density, does it follow that less air is transferring through the root system than a tree that gets freely watered every day?

 

[Paradox]

It really depends on what you have it mixed with and how much. It also is important to have good quality hard akadama

I use 1:1:1 akadama : pumice : lava for my pines, junipers and 2:1:1 A : P : L for my maples and others that like a bit more moisture.

The reason people use akadama is because it holds a bit more moisure than pumice and lava but isnt sopping wet. Thats the point. In the ratios I use, the lava and the pumice hold the soil structure and keep it draining freely and air moving through which is what you want.

By the time I see the akadama break down to really small particles, its time or even past time for a repot anyway.

 

[Joe Dupre']

Thanks, Paradox. I really meant the use of pure akadama. Somehow, it just makes me think that pure akadama would end up as a solid, soggy brick. The only thing I can maybe conjure is that the overabundance of fine roots allows the soil to drain and breathe............acting like a free-draining aggregate.

 

[Deleted member 32750]

Pure Akadama works well with high water mobility species like Japanese and Trident maples. Thats about the only scenario I would use just Akadama. As Paradox mentioned It's typically mixed with other components like Pumice, Lava, Kiryu, or Kanuma depending on what species you are dealing with.

 

[Lorax7]

Didn’t occur to me at the time, but I really should’ve taken a picture this weekend when I was repotting a lilac that had been in its pot for a few years. It was a cheap, mass produced pot and the pot cracked over the winter and a piece fell off the side. Anyway, when I pulled the rootball out of the pot, it was a textbook example of everything you could hope for in terms of roots for a bonsai. Just this incredibly ramified uniformly dense network of fine feeder roots everywhere. I haven’t seen anything like that in another growing medium that lacks akadama. That’s why I still pay for expensive Japanese dirt.