Bonsai soil

[Brent99]

Good evening everybody,

I asked a while ago about bonsai tips and you guys gave me great tips and tricks. Thanks again! But I also started reading about bonsai (I got myself a book, "The bonsai handbook"). But I was reading about bonsai soil and there was a lot of useful information but also a very easy "recipe" to make your own bonsai soil. It said that the roots can rot if I only use normal potting soil. But they said that using 50% organic material (for example humus) and 50% grit (for example lava stone) is a easy, cheap and good recipe for most bonsai. Can this work? And what's important to look after (layers for example or is it just a mix)? I of course understand that using akadama, kanuma etc will be better after a while but I was curious if this method would also work. Thanks already for your help!

Kind regards,
Brent

 

[MSU JBoots]

This is a question many have asked and everyone has an opinion on. I think it’s generally accepted that you want a well draining soil and often mostly inorganic. I personally just buy bonsai jack organic mix. It’s mostly inorganic with some pine bark mixed in so I don’t have to worry about watering as much as I work full time and have 2 young kids. Lots of things can work. The best thing is just try some different things and find what works for you with your trees, your climate, and your time. So really… it depends.

 

[TrevorLarsen]

I use a perlite coco coir mix. Just make sure you sift the perlite which means you will waste a lot of dust. Here is a good video.

 

[Brent99]

This is a question many have asked and everyone has an opinion on. I think it’s generally accepted that you want a well draining soil and often mostly inorganic. I personally just buy bonsai jack organic mix. It’s mostly inorganic with some pine bark mixed in so I don’t have to worry about watering as much as I work full time and have 2 young kids. Lots of things can work. The best thing is just try some different things and find what works for you with your trees, your climate, and your time. So really… it depends.

Haha, I saw it indeed that the type of soil is a pretty risky topic because everybody has their own opinion about it but thanks a lot for your answer!

 

[Brent99]

I use a perlite coco coir mix. Just make sure you sift the perlite which means you will waste a lot of dust. Here is a good video.

Thanks a lot, I'll watch the video!

 

[River's Edge]

Check out the resource section of this website! Introductory soil physics part 1 and 2. Will help you to weigh the variety of opinions with some facts!

 

[Paradox]

50% organic material might work for trees that like to stay on the moist side, but will probably stay too wet for pines and juniper.

 

[Orion_metalhead]

Grow Out: 1:1 compost, perlite... I add an extra part pea gravel for conifers.

In pots:
Deciduous: 1:1:1 compost, perlite, saf-tsorb
Conifer: 1:1:1 perlite, pea gravel, Saf-tsorb with some crushed pine bark mixed in.

Has worked well past couple years for me and gets me through the hot days with not much wilting/drying out. For trees that like to be wet, I increase the compost to perlite ratio.

 

[ACooke]

Sorry to hijack this.
How crucial is sifting the perlite (or similar)?
As time has gone on, my sifting has gone from diligent to does-not-do-at-all (lazy/messy).
I haven't really *noticed* any issues with not sifting but I presume the potential issues would be 'caking', and drainage blockages?
Is there anything else I should be concerned about? Soil clumping?

As far as soil - I've experimented a little but typically use a mix of Perlite and a big-box-store 'bonsai' soil; sometimes some peat.
I'd like to add the disclaimer that: I have minimal idea what in the hell I'm doing, and I have no trees in later development stages yet, or that would be tragic to lose.

 

[TrevorLarsen]

Yeas the problem as far as I know is that the drain holes would be clogged sooner or later probably sooner. It’s an even bigger problem if you have a pine that you won’t repot for 3 years. Also the powder will hold more moisture than you want and won’t allow air that the roots need to breathe. It’s a big deal.

 

[Deep Sea Diver]

Sorry to hijack this.
How crucial is sifting the perlite (or similar)?
As time has gone on, my sifting has gone from diligent to does-not-do-at-all (lazy/messy).
I haven't really *noticed* any issues with not sifting but I presume the potential issues would be 'caking', and drainage blockages?
Is there anything else I should be concerned about? Soil clumping?

As far as soil - I've experimented a little but typically use a mix of Perlite and a big-box-store 'bonsai' soil; sometimes some peat.
I'd like to add the disclaimer that: I have minimal idea what in the hell I'm doing, and I have no trees in later development stages yet, or that would be tragic to lose.

This all about H2O/O2 exchange via the interstitial spaces between particles. Tree roots give off CO2 and take on H2O and O2. There needs to be air spaces for this exchange to be efficien…. or even occur.

We strongly encourage newer hobbyists to download a copy of @markyscott ‘s Introductory Soil Physics 1.2 as @River's Edge suggested.
In addition Inorganic Soil Reference Sheet 1.2.

Media is both a complicated topic….and on all bonsai forums recommended media can be controversial that has many facets and caveats.

Many folks have a couple or three perfect mixes/sizes that work for their trees and their level of tree care. But there are many others with different media mixes they have found work extremely too in their own areas.

For example @Orion_metalhead has really nice results with his mixes in his area. We get similar results with different mixes in our area.

A lot of this variation has to do with availability of product, climate and many other things. (Mentors, goals, micro climate, experience, age/type/development of trees, budget etc) It gets even more problematic when folks in the very same area discuss their own go to mixes!

Since you are in Sydney, perhaps @Shibui can add some suggested mixes for your area.

cheers
DSD sends

 

[Orion_metalhead]

I think in general, as you start getting trees further along in development and past the grow out phase, mixes will change to suit the tree. The more refined the tree, the less repotting it will be experiencing, and so you will need to adjust mixes for structural longevity. Spending $100 on soil components that you're replacing every year is a lot, but that cost seems worth it when you're not repotting an advanced tree for four or five years.

Also, thanks @Deep Sea Diver, for the compliment! I don't think I'm doing anything particularly incredible but it's sometimes tough to tell when branches are poking you in the eye.

 

[ACooke]

Thanks for the replies to my questions.
I should have watched the above video before i commented as perlite (or pumice in this case) clumping was partly mentioned.

The substrate mix i’m using seems to be working quite well here in Sydney so was more a question specifically as to perlite dust/sifting. Regardless, i’ll certainly read the articles posted - thank you!

 

[Shibui]

Since you are in Sydney, perhaps @Shibui can add some suggested mixes for your area.

Only that it has been demonstrated that we can grow great bonsai in a wide range of mixes provided we can match watering and fertilizer to the specific mix used.
Open, inorganic mixes seem to give the best insurance policy against less than perfect care.
There's far more leeway when growing trees in larger and deeper grow containers than in small, shallow bonsai pots so potting mixes are less critical in the early, growth stages.

 

[The Warm Canuck]

Good inorganic Bonsai soil can be an investment though. You can re-use it. Pumice and Lava that is.

 

[Paradox]

Good inorganic Bonsai soil can be an investment though. You can re-use it. Pumice and Lava that is.

Yes. I've cleaned and reused lava and pumice after repotting a healthy tree. A lot of the time it sits in a bucket for a year before I get around to cleaning (resifting) it

 

[dbonsaiw]

There’s a lot involved in soil and this tends to lead to arguments, but we can keep it simple. You want drainage, aeration and water retention. Bonsai jack universal organic mix works well for me and my trees in development. It’s priced much better when buying in bulk. I will also reuse the soil after a repot for other trees in larger containers and mix it with more organics.

 

[Deep Sea Diver]

Yes. I've cleaned and reused lava and pumice after repotting a healthy tree. A lot of the time it sits in a bucket for a year before I get around to cleaning (resifting) it

We process and recycle akadama, pumice and lava constantly. Akadama recovery is usually 50-75, the rest 90-95% due to particle breakdown. Heat treating in the process actually makes the akadama a bit harder, temperature dependent.

Occasionally we get a lot from someone who does not know how to properly work akadama that has lower percentage… one where the trees weren’t repotted in a decade….

Just finished a 3 gal batch…. Needs sifting


Cheers
DSD sends

 

[MSU JBoots]

@Deep Sea Diver and @Paradox do you mind sharing briefly how you clean used soil?

 

[Deep Sea Diver]

Sure. My method is a bit more time consuming then others.

1. Rinse out roots & fines. We use wheelbarrow or bucket for small lots.

2. Scoop Media (some fines will still be present.) into colander and finish rinsing.

3. Drain much as possible.
********
At this point one can simply doe spread out and dry the media in the sun. We don’t have this luxury during the major part of the growing season,

4. Put in old aluminum/steel baking pans. 12x17? (Got from Salvation Army 5 yr ago. Heat to 350-450 90 mins max. (Using 450 mostly) Run exhaust fan. We use four pans at once for largest load. Take out, cool.
******
5. Sift media larger to smaller sizes.
Larger drainage layer,
Mid bonsai media,
Smallest Projects
Fines for muck

6. Assess final result.
Add akadama etc as needed, Conifer/Deciduous etc,
Also at same time add Biochar 5%
Mix in small lots into water tight storage. (5g bucket and the black flex lids work well. Home Depot lids not as well.)

Upsides.
-Much less sifting.
- Media is dry and ready to handle in 1-2 hours
- Relatively sterile mix. Never had issues
-Akadama hardens becomes a bit more durable. (If kept dry.).
- Especially good if someone ships you a load with softer akadama. In fact once I just heated the entire bag. All was good.
- Yields about 3+ gallons
- Can do with kanuma too. Need to be gentle. Can use lower temps 350.
- Biochar/Hortchar won’t burn at these temperatures.
- Only purchase 1/3 akadama. Went two years before we thought to get more.

Downsides
-Can smell if rinsed inadequately. Don’t use method if media has wood in it. If so wait until wife and kids have left! May be best to air/sun dry these mixes. Btw
- Some partners don’t like using the oven for this! My better half does bonsai and likes to save money. All it took to convince her was to show the receipts for the raw ingredients!

Cheers
DSD sends