Sand in soil.

[maroun.c]

I see many bonsai soil.mixes have sand in them. How do you manage the sand not to go down through the larger particle and accumulate down in the pot? Is it best to use sand to fill the empty spaces between larger particles soil so theres no air there to affect roots or is a little bit of air in the soil beneficial for roots?
Thanks

 

[Tidal Bonsai]

Everyone has their own mix, so I hope this doesn’t start a soil war. If you are talking about typical sand like you would use in a sandbox, this is something I only use for trees in development. I use about 2/3 broken down wood chips and 1/3 sand. The broken down bark keeps it from going through drainage holes, but these trees are in larger pots for development.

If youare talking about traditional river sand in Japanese mixes, this is a larger particle size that I believe is similar to our pumice.

 

[Yamabudoudanshi]

I have been using a mix of Akadama/Kiyru Sand (a Japanese river sand as Brewing^ mentioned) at a 70/30 ratio with the conifers. The sand particles vary in size so I match grades with my akadama particles: coarse, fine, semi-fine. So I don't have any issue with particles making their way down.

 

[Anthony]

silica based gravel 5 mm

 

[rockm]

I see many bonsai soil.mixes have sand in them. How do you manage the sand not to go down through the larger particle and accumulate down in the pot? Is it best to use sand to fill the empty spaces between larger particles soil so theres no air there to affect roots or is a little bit of air in the soil beneficial for roots?
Thanks

You're using sand that is too fine. As explained above, with bonsai soil "sand" is very different than what you typically think of. Playground sand, construction sand and most of the more commonly available stuff that's commonly used for a lot of things other than bonsai is far too fine and will wind up at the bottom of a bonsai pot, or even washed out the drain holes.

What you're after is very coarse "sand"-- Horticultural sand similar to this--although this is a bit coarse...

Amazon.com : 5 Quart Coarse Sand for Succulent, Bonsai Tree & Carnivorous Plant Soil Mix : Garden & Outdoor

Amazon.com : 5 Quart Coarse Sand for Succulent, Bonsai Tree & Carnivorous Plant Soil Mix : Garden & Outdoor

www.amazon.com

 

[Gustavo Martins]

I believe fine sand is good for cuttings.

Other than that I don’t think it’s very useful. And yes, roots need air.

 

[Shibui]

Roots definitely need air so a good potting mix needs to have air spaces in it. Spaces for water and roots and air.
Sand particles need to be similar size to the other parts of your mix. Sieve out fine particles before adding anything to your bonsai mix.

 

[Potawatomi13]

Using dry "before" mix use 1/8 filter screen and sift out before using. Otherwise guaranteed to filter self to nether regions of pot.