Soil mix decision

[badatusernames]

What decision process do you go through when deciding which soil mix to use?

As someone newly taking a look at this, it seems as though everyone has their own formula that they tend to use, and I'm curious to hear from folks as to why they settled on what they did.

So far, my experience has primarily been with tropicals, and I've simply used Tinyroots tropical blend. As I branch into conifers and deciduous trees more, I want to make sure I'm thinking about this appropriately.

To use the Tinyroots tropical blend as an example (as I know they also have conifer and deciduous blends), is the purpose for mixing your own primarily around quality of soil, or is it simply that buying pre-made soil becomes prohibitively expensive?

Anyways, I imagine that as with anything with variables that folks draw their own conclusions about, this could be opening a can of worms, but I was curious to hear if this is something I should delve into deeper for the health of my trees, or if I should keep my focus on other aspects of horticulture and styling as I get deeper into this world, saving soil mixing for when I'm ready to experiment with more variables.

 

[just.wing.it]

buying pre-made soil becomes prohibitively expensive?

Probably.
I depends on your microclimate and how much sun and wind they receive coupled with how often you intend to water.
My trees are mostly all in Lava, Pumice and Bark chips and get full sun from late morning on. I'm also on the top of a hill and usually have a breeze. That said, in the summertime I water once in the morning and once in the evening...sometimes less.

 

[Kanorin]

To use the Tinyroots tropical blend as an example (as I know they also have conifer and deciduous blends), is the purpose for mixing your own primarily around quality of soil, or is it simply that buying pre-made soil becomes prohibitively expensive?

Probably a bit of both. Some people have 50, 100 or more trees and the big ones can take close to a full 13L bag of soil.

Choosing soil components is a pretty deep (and often heated) topic. There are many threads on it. A lot of variables can influence these decisions including: What climate you are in, how often you are able to water, how deep your pot is, what species of tree it is, how long you can go between repots.

If you ask 10 different people, you'll probably get at least 6 different answers. I'd say that many of the pre-mixed blends or a mix of 1:1:1 (or close) Pumice/akadama/lava are quite good for beginners (myself included) in most climates for keeping most of the common bonsai species.

 

[sorce]

Soil is such an "issue", that I decided the best route was to use what I know I can always get, Napa #8822, and grow what lives well in it.

The fact that it fluffs up when it freezes rather than compacting is a bonus up here.

No trees hate it. Reckon a few people do though!

Sorce

 

[BrianBay9]

You can grow your trees in pretty much anything if you tailor your watering and fertilizing to they type of soil used. That's why you see so many different mixes. People are passionate about their mix because they found it works for them. The critical attributes for a generally successful mix seem to be making it free draining, retains sufficient moisture (and not too much) for your microclimate and care, and is well aerated. Lots of mixes can satisfy these attributes. If yours is working well for you, stick with it.

 

[leatherback]

This is my decision process..:

Characteristics of good bonsai substrate - Growing Bonsai

When growing bonsai, there are few subjects that are more controversial than substrates. To some the concept of not using the Japanese substrates is near blasphemy. Everything that is used …

www.growingbonsai.net

Effectively I follow Walter Palls thinking; Substrate is there to hold water till next watering. And to cover the roots. Then you want to keep fertilizer in there untill the tree has time to absorp. Not much of a thing to spend a lot of time thinking about. Then again.. We do!

 

[Bnana]

I fully agree with leatherback, substrate is there to hold water and nutrients while allowing oxygen to reach the roots.
There is a tiny addition that some trees like a low pH. For most species you can ignore that.

 

[badatusernames]

This is my decision process..:

Characteristics of good bonsai substrate - Growing Bonsai

When growing bonsai, there are few subjects that are more controversial than substrates. To some the concept of not using the Japanese substrates is near blasphemy. Everything that is used …

www.growingbonsai.net

Effectively I follow Walter Palls thinking; Substrate is there to hold water till next watering. And to cover the roots. Then you want to keep fertilizer in there untill the tree has time to absorp. Not much of a thing to spend a lot of time thinking about. Then again.. We do!

Cat litter... that's amazing. I literally couldn't tell if @sorce was pulling my leg regarding the Napa 8822 but hey, if it fits the need...

 

[Clicio]

Cat litter... that's amazing. I literally couldn't tell if @sorce was pulling my leg regarding the Napa 8822 but hey, if it fits the need...

Yeap, I've been using cat litter or DE as a component of my soil from 2017 on.
It works well in my mix.
There is Lava rock, peat+perlite and pine bark also.
But...I am in the tropics.
Pines and Junipers get more perlite and lava rock, Azaleas get more pine bark.

 

[Carol 83]

No trees hate it.

Bougies do. Stays too wet, too long.

 

[Bnana]

There are a lot of opinions on different soil components. This also depends on the species of trees, climate and watering regime.
For me the high water holding capacity of the coarse cat litter (mixed with bark) is great for thirsty larches and deciduous trees in summer. As it's an open structure that lets air in therefore wet doesn't mean low oxygen.

 

[Arlithrien]

What decision process do you go through when deciding which soil mix to use?

As someone newly taking a look at this, it seems as though everyone has their own formula that they tend to use, and I'm curious to hear from folks as to why they settled on what they did.

So far, my experience has primarily been with tropicals, and I've simply used Tinyroots tropical blend. As I branch into conifers and deciduous trees more, I want to make sure I'm thinking about this appropriately.

To use the Tinyroots tropical blend as an example (as I know they also have conifer and deciduous blends), is the purpose for mixing your own primarily around quality of soil, or is it simply that buying pre-made soil becomes prohibitively expensive?

Anyways, I imagine that as with anything with variables that folks draw their own conclusions about, this could be opening a can of worms, but I was curious to hear if this is something I should delve into deeper for the health of my trees, or if I should keep my focus on other aspects of horticulture and styling as I get deeper into this world, saving soil mixing for when I'm ready to experiment with more variables.

Needs of the tree come first. Cost and availability determines what I have in my arsenal. I prefer components I can source cheaply and readily. You wont see me using akadama or anything imported unless it's on sale.

If the species isn't picky, I'll throw it in pure DE. If it doesn't like wet feet I'll add a drainage component like chicken grit or lava. If the tree needs some acidity or organic component Ill add pine bark. If it's a recently collected tree in recovery I'll throw it in pumice and shredded sphagnum moss.

 

[Rivka]

The term pumice seems to mean a lot of different things. Some being softer than others. Can anyone explain that a bit?

 

[canoeguide]

You can grow your trees in pretty much anything if you tailor your watering and fertilizing to they type of soil used. That's why you see so many different mixes. People are passionate about their mix because they found it works for them. The critical attributes for a generally successful mix seem to be making it free draining, retains sufficient moisture (and not too much) for your microclimate and care, and is well aerated. Lots of mixes can satisfy these attributes. If yours is working well for you, stick with it.

This should be stickied at the top of every thread about soil. Fantastic summary and explanation of why everyone has their own thoughts.

 

[Kanorin]

The term pumice seems to mean a lot of different things. Some being softer than others. Can anyone explain that a bit?

I just heard an explanation for this on the bonsai wire podcast. Apparently the density of pumice changes depending on how deep it is in the particular vein that is being mined. So even from the same company the 2019 pumice may be quite a bit different than the 2021 pumice, for example.

 

[Leo in N E Illinois]

Not everyone can water daily. All my trees are potted one way or another so that they can be watered every 3rd day. This allows a weekend away from home. Larger pots or a more water retentive mix is the way I go. For some trees, whose natural habits allow it, sit in trays of water while I am travelling. For example bald cypress, willows, red maples, metasequoia, and others that tolerate standing water. Not everyone can live a life and water daily.

 

[leatherback]

Not everyone can water daily. All my trees are potted one way or another so that they can be watered every 3rd day. This allows a weekend away from home. Larger pots or a more water retentive mix is the way I go. For some trees, whose natural habits allow it, sit in trays of water while I am travelling. For example bald cypress, willows, red maples, metasequoia, and others that tolerate standing water. Not everyone can live a life and water daily.

How do you deal with extended periods of rain?
I cater for not drowning plants in those 3-week rain periods we can get. Which means that in summer I am watering a lot..

 

[ShadyStump]

Not everyone can water daily. All my trees are potted one way or another so that they can be watered every 3rd day. This allows a weekend away from home. Larger pots or a more water retentive mix is the way I go. For some trees, whose natural habits allow it, sit in trays of water while I am travelling. For example bald cypress, willows, red maples, metasequoia, and others that tolerate standing water. Not everyone can live a life and water daily.

This is where I'm aiming as well. Added are the facts that I'm flat broke and live in the ROCKY Mountains so find it hard to justify spending money on aggregate when so much of it abounds around me. Consequently, a good chunk of my tree losses involve experiments with soil components from the yard, the ditch, the roadside, etc. Eventually I'll know exactly what to expect from any given soil mix, and never pay the stuff ever. The stickiest issue so far has been drainage vs nutrient containing components. Mix in anything that might be considered the regular soil from the ground and it turns to anaerobic sludge as soon as it's wet. SO MUCH CLAY IN OUR SOIL.

 

[Paradox]

Bottom line how healthy your trees are is dependent on your soil.
Root problems due to bad soil conditions are one of the main causes of illness and death in your trees.
It doesnt pay to compromise on good soil IMO. I tried the "Im not going to pay for dirt and use what is available around me" and it didnt work great.
Trees that are not vigorous, sick or dead trees cant be made into bonsai.

Yes like most hobbies, you have to spend some money to participate.
Scale (ie the number of trees you have) is the way to keep costs under control.
Having fewer, healthier trees in good soil is better than a lot of unhealthy trees in crap soil.

 

[leatherback]

flat broke and live in the ROCKY Mountains

THis makes me think.. Yamadori collecting, selling & earning money for pots and wire!