Bonsai jack soil? BYOS

[drip]

Anyone use the build your own soil from bonsai jack? Never heard of bonsai block and this other stuff, is it as good as the classic akadama/lava/pumice mixes? Chatgpt told me to use 40% bonsai block/25% monto clay/20% lava/15% fir bark for my japanese maple going into an anderson flat this spring. Any bonsai jack haters or enthusiasts out there? Thanks.

 

[Rivian]

For JM, you could use pure pumice, or pure akadama, or any mix of the two, potentially with some kanuma or bark or biochar as well.
Dont use lava for your purposes
Dont know the other things you mentioned

 

[drip]

For JM, you could use pure pumice, or pure akadama, or any mix of the two, potentially with some kanuma or bark or biochar as well.
Dont use lava for your purposes
Dont know the other things you mentioned

Apparently bonsai block is like akadama and monto clay is like pumice, or something like that. Honestly first time I heard of it. Why is lava not good here?

 

[Rivian]

I dont really trust "is like akadama", reminds me of sakadama, which no-one brings up anymore.

Why is lava not good here?

Is Lava Good For Bonsai?

This is a legitimate question. My master Shinji Suzuki never used lava (aka scoria), preferring just akadama and pumice. On coming back from Japan in 2006 I continued using the akadama / pumice mix…

crataegus.com

On Pumice: https://crataegus.com/2025/02/28/100-pumice-as-soil/

 

[Maiden69]

Apparently bonsai block is like akadama and monto clay is like pumice

Wrong,

Bonsai Block is a substitute for black lava, without all the sharp edges. Monto Clay is the same as turface, just in a rounder shape, not flat. Both are decent compounds and what I use on trees that are in development inside grow bags. For teres in anderson flats just use some kind of organic mixed with pumice at a 70% org to 30% pumice or even perlite. Inorganics need to be watered frequently, so unless you can water multiple times a day stay with more organic compounds. Akadama should be used only when the tree goes into a pot, not for development.

There is a lot more info if you search the website for either bonsai block or monto clay.

 

[Port Farmer]

What is BonsaiBlock? – Bonsai Jack ©

www.bonsaijack.com

I've mixed BYOS (Lava/Bonsai Block) with Pumice and Coco Coir (prebonsai, no maples). If you use anything with Monto, double check the size. There was a notice somewhere about them no longer being able to source the larger 1/4" size so I think they are reverting back to regular sized turface.

 

[dbonsaiw]

At the risk of being labelled a "bonsai heretic", I stopped giving so much thought to soil mixes. I use the traditional Bonsai Jack premix on basically everything and it works for me. (I do not have any "finished" trees, FWIW).

 

[Kievnstavick]

I recently bought bonsaiblock as I didn't have the time to go to my local landscape supply and sift lavarock.

The only time I have BYOS was for my potted blueberries when I was just getting into bonsai. I had this amazing idea that all potted plants should get repotted into well draining aggregate. I tailored the mixture for acid loving plants while also having a high percentage of bark for water retention.

It has worked well over the years (the blueberries are on year 6 in the same substrate), but I definitely didn't need the expensive mixture for the plants. Hindsight is 20/20. I don't regret spending the extra on the BYOS, but I am satisfied with the results so far.

 

[Wulfskaar]

I've ordered from Bonsai Jack a few times, but only the pre-mixed bags.

My conifers seem to like their conifer mix. I just add a little reptibark since I'm in a place with no rain for 3/4 of the year.

Last year I placed an order and got a different mix. I have no idea what the components are, but I used it anyways.

They also toss in a metal chopstick, which can be very useful.

 

[Bonsai Nut]

According to their product description, Bonsai Block is calcined clay... aka the exact same product as Turface, albeit in a different size/shape.

I don't have as much money as y'all to be buying all these high-end soil components that cost over $50 per 5 gallon bucket. I'm in the process of bringing in 2 cubic yards of pumice from Colorado for about $950 delivered. That's about 400 gallons for $950... or about $2.36 per gallon.

 

[Michigan Tree Murderer]

According to their product description, Bonsai Block is calcined clay... aka the exact same product as Turface, albeit in a different size/shape.

I don't have as much money as y'all to be buying all these high-end soil components that cost over $50 per 5 gallon bucket. I'm in the process of bringing in 2 cubic yards of pumice from Colorado for about $950 delivered. That's about 400 gallons for $950... or about $2.36 per gallon.

Sold! I'll take ten gallons. That's a sweet deal.