Newbie Soil discussion

[eugenev2]

Soil mediums


Hi All,

I’m relatively new to bonsai, why relative, I had some experience a few years back, but this was closer to pot plant experience rather than bonsai, long story short, all the trees died, and I put aside the hobby for another day. Covid came around a provided me with ample time to be back home and so I restarted the hobby.

Now to the real question…Soil mediums

I realize this a very controversial topic and people get very upset and emotional about it (I don’t know why…isn’t all about the trees in the end?), but the part of this discussion that I still cannot grasp is as follows…akadama and the inorganic fast draining mixes is the holy grail of bonsai, organic is the friend of root rot and should be avoided. Does this some it up accurately?

Disclaimer, I realize soil mixes are very dependent on your climate, average temperature, number of freeze/thaw cycles, your ability or inability to water frequent, availability, species of plant and finally cost…did I forget anything?

Now the part I’ve been struggling with is that everything indicates that akadama is the best for my trees, until I tell people my trees are relatively young ie less than 10 years old (although the one hand-me-down might be about 15/20 years old), the tune changes immediately and I’m told that I should rather use inexpensive fast draining organic based mediums. But why if akadama is good should it not be good for start trees as well? If organic is so bad, why is it good for starter trees? And I know everybody tells me rather ask your local experts…well I have…asked two relatively well-known local experts and their views where vastly divergent, one was pro inorganic, and one was pro-organic. Both got really upset with me and my questions. Ironically both ended the conversation with…just look at my trees, see how healthy they are.


So can someone please oh please explain the why?

 

[rockm]

Would help if you provided geographic location, as well as species you're using. Can make a difference in what might be used. There are no absolutes here. Anyone who gets upset about using organic or inorganic is misguided. It can be both, depending on what you want and what your local environment demands (your locality can play a very important role in your soil choices).

In general, what you're running up against is personal preference/what works. Akadama is hardly the best soil for all trees. It is not really meant to be used by itself. It can break down (there are many "grades of akadama), or not (high fired Akadama does not break down). Breakdown also isn't a bad thing...

Organic components have their uses, depending on species, deciduous mixes tend to have organics, conifer mixes don't. That is because conifers tend to like fast draining soil, which has to do with where many grow naturally--alpine, seaside environments...Deciduous species tend to originate in places that have denser, richer soils...This is obviously a sliding scale and can be manipulated in artificial environments such as pots.

Organic soil CAN BE the friend of root rot. It's much easier to induce conditions that foster it in soil with a lot of organic components. Also fast-draining inorganic soils can foster conditions that dry roots out. Avoiding both extremes is up to the user, not the soil

 

[Mikecheck123]

There's only one thing to know: uniform particle size. Everything else is noise.

The one thing you need to adjust for your climate is particle size. Smaller if you need to hold more water and larger if you need more drainage. But always uniformly sized particles.

The akadama thing is mostly about finished trees, so I wouldn't worry about using it. You have to be pretty far in to tell a difference, and given the cost, it's not worth it for you.

 

[dbonsaiw]

I agree that much of this is personal preference. I also don't believe this needs to be approached like rocket science. It's nothing more or less than drainage, aeration and water retention. Species, climate, stage of development etc. will all play into the calculus of what substrates we choose to make up this trinity. Organics will provide more water (and nutrient) retention as well as feeds the tree. So, your choice of soil substrate will also be intimately tied to your watering and feeding "schedule".

My rule of thumb in bonsai is that if I don't know why I'm doing/using something, I simply don't do it or use it. If Akadama was really the holy grail, you'd understand why. It's not the holy grail, it's a personal preference. In fact, many people that experience colder winters will not use akadama as it breaks down from the freeze/thaw cycle. I try to keep soil as simple as possible (basically 80% organic/20% inorganic) and change that setup if I understand why I'm adding or taking something away.

From this simple premise the issue can be complicated as much as one wants to go down the rabbit hole.

 

[eugenev2]

Would help if you provided geographic location, as well as species you're using. Can make a difference in what might be used. There are no absolutes here. Anyone who gets upset about using organic or inorganic is misguided. It can be both, depending on what you want and what your local environment demands (your locality can play a very important role in your soil choices).

In general, what you're running up against is personal preference/what works. Akadama is hardly the best soil for all trees. It is not really meant to be used by itself. It can break down (there are many "grades of akadama), or not (high fired Akadama does not break down). Breakdown also isn't a bad thing...

Organic components have their uses, depending on species, deciduous mixes tend to have organics, conifer mixes don't. That is because conifers tend to like fast draining soil, which has to do with where many grow naturally--alpine, seaside environments...Deciduous species tend to originate in places that have denser, richer soils...This is obviously a sliding scale and can be manipulated in artificial environments such as pots.

Organic soil CAN BE the friend of root rot. It's much easier to induce conditions that foster it in soil with a lot of organic components. Also fast-draining inorganic soils can foster conditions that dry roots out. Avoiding both extremes is up to the user, not the soil

So geographic location is Johannesburg, South Africa.

Species is a wild mix (Some are for experiments...ie how far i can push before killing them)
Senegalia galpinii/monkey thorn (Age +/- 7 years)
Senegalia burkei/Black monkey thorn (Unsure about the age, gentleman that gave it to me said he grew it for the last 10 years...so 10 years +)
Jacaranda mimosifolia/Jacaranda (About 1 year old now)
Pinus thunbergii/Japanese Black Pine (Age +/- 4 years)
Random Pine seedling/Possibly loblolly pine (Age unknown)
Acer palmatum/Japanese Maple (Age unknown probably +/-5 years)
Juniper procumbens nana/Juniper (Age unknown)
Taxodium distichum/Bald cypress (Age +/- 4 years)
Acer buergerianum/Trident Maple (Age unknown came in a 20L nursery bag)
Rhododendron indicum(Possibly)/Azalea (Age unknown came in a 20L nursery bag)
Buxus sempervirens(Probably)/Boxwood (Age unknown came in a 10L nursery bag)
Bougainvillea (Age unknown came in a 10L nursery bag)
Celtis sinensis/Hackberry Celtis africana/White Stinkwood (Randomly sprouted in the garden and about 1 year old now)

 

[rockm]

So geographic location is Johannesburg, South Africa.

Species is a wild mix (Some are for experiments...ie how far i can push before killing them)
Senegalia galpinii/monkey thorn (Age +/- 7 years)
Senegalia burkei/Black monkey thorn (Unsure about the age, gentleman that gave it to me said he grew it for the last 10 years...so 10 years +)
Jacaranda mimosifolia/Jacaranda (About 1 year old now)
Pinus thunbergii/Japanese Black Pine (Age +/- 4 years)
Random Pine seedling/Possibly loblolly pine (Age unknown)
Acer palmatum/Japanese Maple (Age unknown probably +/-5 years)
Juniper procumbens nana/Juniper (Age unknown)
Taxodium distichum/Bald cypress (Age +/- 4 years)
Acer buergerianum/Trident Maple (Age unknown came in a 20L nursery bag)
Rhododendron indicum(Possibly)/Azalea (Age unknown came in a 20L nursery bag)
Buxus sempervirens(Probably)/Boxwood (Age unknown came in a 10L nursery bag)
Bougainvillea (Age unknown came in a 10L nursery bag)
Celtis sinensis/Hackberry Celtis africana/White Stinkwood (Randomly sprouted in the garden and about 1 year old now)

Put the local info in your profile. It helps for that info to follow alongside your posts.

I can't really offer much on what to use, since you're an ocean away and have a unique climate. Not familiar with many of the tree species you're using.

FWIW, bald cypress will grow in just about anything, as long as it's soggy. Japanese and trident maples do well in "all purpose" bonsai soil. Boxwood tend to like freer-draining soils and shallower pots, along with a dash of organic (I use composted pine bark)...Pines tend to do best in inorganic mixes.

 

[eugenev2]

There's only one thing to know: uniform particle size. Everything else is noise.

The one thing you need to adjust for your climate is particle size. Smaller if you need to hold more water and larger if you need more drainage. But always uniformly sized particles.

The akadama thing is mostly about finished trees, so I wouldn't worry about using it. You have to be pretty far in to tell a difference, and given the cost, it's not worth it for you.

@Mikecheck123, how do you enforce this with something like peat moss/garden compost, which is generally very fine in comparison to most components? Or do you control this by keeping the percentage relatively low?

 

[eugenev2]

Put the local info in your profile. It helps for that info to follow alongside your posts.

I can't really offer much on what to use, since you're an ocean away and have a unique climate. Not familiar with many of the tree species you're using.

FWIW, bald cypress will grow in just about anything, as long as it's soggy. Japanese and trident maples do well in "all purpose" bonsai soil. Boxwood tend to like freer-draining soils and shallower pots, along with a dash of organic (I use composted pine bark)...Pines tend to do best in inorganic mixes.

Thanks for the advice, will make a note of these

 

[rockm]

@Mikecheck123, how do you enforce this with something like peat moss/garden compost, which is generally very fine in comparison to most components? Or do you control this by keeping the percentage relatively low?

The answer is don't use peat moss and garden compost. Both are too fine and wash to the bottom of the pot, where they clog drainage. They also become water repellant if they dry out.

Organic components should themselves be kind of durable and angular and chunky. "Organic" doesn't mean fine particles. For instance a good organic component can be composted pine bark, sifted to remove fines. You can find composted pine bark sold as "clay buster" soil amendments at landscape supply places. Make sure what you're looking at is pine bark, only.

Also some growers use the smallest grade of orchid bark.

Gardeners 2 cu. ft. Orchid Seedling Bark 8067 - The Home Depot

This Gardeners 2 cu. ft. Orchid Seedling Bark is a quality bark product specially selected and processed for orchid propagation and cultivation. It provides good aeration and drainage suitable for growing

www.homedepot.com

What Is a Pine Bark Soil Conditioner?

Pine bark works as a soil conditioner provided it is properly prepared. While finely...

homeguides.sfgate.com

 

[Mikecheck123]

@Mikecheck123, how do you enforce this with something like peat moss/garden compost, which is generally very fine in comparison to most components? Or do you control this by keeping the percentage relatively low?

By not using it.

 

[VAFisher]

Turface is the best! Turface is the best!

 

[mike3m]

Turface is the best! Turface is the best!

who's do you use and where do you source in VA

 

[VAFisher]

who's do you use and where do you source in VA

I was joking around because people can get so passionate about this topic, and Turface in general. People should use whatever works for them or what they can get easily. I experimented a lot in my early days and settled on Turface, small lava rock and pine bark as my 3 main ingredients. I change the ratio depending on species and water needs. I might also add some potting soil in there for things like BC and Water Elm. It works for me. I changed to this because my trees were wilting by the time I got home from work, so I needed more water retention.

I get my Turface from Amazon.

 

[rockm]

who's do you use and where do you source in VA

If you have to use it, you can get it at agricultural stores, like Southern States, seed and feed stores, etc. also landscape supply (it's used on the infields of baseball fields too)

Turface MVP | Landscape Supply

Landscape Supply Inc - We supply landscape and turf professionals with great solutions and even better service. For over 60 years, the mid-Atlantic region has depended on us as a trusted partner in the green industry.

www.landscapesupplyva.com

Turface MVP - Newsom Seed

No other infield conditioner has been used on more diamonds than Turface MVP. Its larger particle size is excellent for incorporating into infield mix, topdressing to create a consistent and level playing surface, helping prevent rain outs, and improving native soil for turf renovations. MVP is...

newsomseed.com

Personally, I've found haydite is a better choice, but harder to source. FWIW, I stopped making my own bonsai soil after 20 years or so. Too much effort for the return. Storing all those ingredients is also a pain in the ass.

Turface CAN work, it can also not. I've seen rampant growth in straight turface from collected boxwoods. I've also seen it smother and kill the roots on other trees.

 

[ShadyStump]

FWIW, I stopped making my own bonsai soil after 20 years or so. Too much effort for the return. Storing all those ingredients is also a pain in the ass.

I'm in year three of pursuing bonsai, and have little to show for it having spent most of that time experimenting with "cheap and free" soil components from whatever was around. THIS is the single biggest reason for soil wars. People are just that traumatized by trying to figure it out.

I've smashed pots and brick and rocks into bits when I've needed courser material, and I've climbed mountains to sift sand and pack it all home, and I've tried everything in between. I have a pretty decent feel for what will and won't make good soil components in a given situation, but in the end it just isn't worth all the effort when I could be doing something more productive.
Seriously, try breaking up enough old bricks small enough to fill a pot or two, and you'll understand why bonsai was a thing for the elite in pre-industrial days. I'm glad I did it all, and I'm glad for what I've learned from it, and I'm glad I live in a place where I have other options.

OP, I'm working with calcined clay floor dry materials right now. I have a good bunch of tropicals in calcined Fuller's earth, and calcined diatomaceous earth on standby when that runs out. Joberg doesn't freeze, so these sorts of products should do alright for your climate. They're available at auto parts shops, hardware stores, livestock feed shops and the like. They come in very small particle size, and you'll need to sift the fines out to keep it from clogging up, but without freeze/thaw cycles to worry about it won't break down in your pot too terribly quickly. Adding a fibrous organic additive, I've found, helps keep the particles from settling too much. I use coco coir, and occasionally other materials depending on the tree's needs. Coco coir- the ground husk of coconuts- expands when it gets wet, and helps push the inorganic particles away from each other, preventing compaction and opening the way for air and roots. This stuff can stay wet for a long time also, while still draining and aerating. It's not the best- especially for trees you're trying to develop nebari on- but it's cheap and effective for my current needs.

 

[mike3m]

If you have to use it, you can get it at agricultural stores, like Southern States, seed and feed stores, etc. also landscape supply (it's used on the infields of baseball fields too)

Turface MVP | Landscape Supply

Landscape Supply Inc - We supply landscape and turf professionals with great solutions and even better service. For over 60 years, the mid-Atlantic region has depended on us as a trusted partner in the green industry.

www.landscapesupplyva.com

Turface MVP - Newsom Seed

No other infield conditioner has been used on more diamonds than Turface MVP. Its larger particle size is excellent for incorporating into infield mix, topdressing to create a consistent and level playing surface, helping prevent rain outs, and improving native soil for turf renovations. MVP is...

newsomseed.com

Personally, I've found haydite is a better choice, but harder to source. FWIW, I stopped making my own bonsai soil after 20 years or so. Too much effort for the return. Storing all those ingredients is also a pain in the ass.

Turface CAN work, it can also not. I've seen rampant growth in straight turface from collected boxwoods. I've also seen it smother and kill the roots on other trees.

I don't mix my own, only been at this since 2018. Best thing I heard early on in my self instruction re soil was to learn from successful local growers what works well for my region. As such, I have been using a mix produced by a local commercial bonsai nursery. They have two kinds, deciduous and conifer, and it has worked well for me up to now. Keeps things pretty simple. VAfisher seems to have figured out what works for him and his trees speak for themselves. Landscape Supply is just down the road but I'm not ready for a 50lb bag of MVP at this point. Gonna leave well enough alone.......

 

[rockm]

I'm in year three of pursuing bonsai, and have little to show for it having spent most of that time experimenting with "cheap and free" soil components from whatever was around. THIS is the single biggest reason for soil wars. People are just that traumatized by trying to figure it out.

I've smashed pots and brick and rocks into bits when I've needed courser material, and I've climbed mountains to sift sand and pack it all home, and I've tried everything in between. I have a pretty decent feel for what will and won't make good soil components in a given situation, but in the end it just isn't worth all the effort when I could be doing something more productive.
Seriously, try breaking up enough old bricks small enough to fill a pot or two, and you'll understand why bonsai was a thing for the elite in pre-industrial days. I'm glad I did it all, and I'm glad for what I've learned from it, and I'm glad I live in a place where I have other options.

OP, I'm working with calcined clay floor dry materials right now. I have a good bunch of tropicals in calcined Fuller's earth, and calcined diatomaceous earth on standby when that runs out. Joberg doesn't freeze, so these sorts of products should do alright for your climate. They're available at auto parts shops, hardware stores, livestock feed shops and the like. They come in very small particle size, and you'll need to sift the fines out to keep it from clogging up, but without freeze/thaw cycles to worry about it won't break down in your pot too terribly quickly. Adding a fibrous organic additive, I've found, helps keep the particles from settling too much. I use coco coir, and occasionally other materials depending on the tree's needs. Coco coir- the ground husk of coconuts- expands when it gets wet, and helps push the inorganic particles away from each other, preventing compaction and opening the way for air and roots. This stuff can stay wet for a long time also, while still draining and aerating. It's not the best- especially for trees you're trying to develop nebari on- but it's cheap and effective for my current needs.

I figured it out. Made my own soils for years. Did it until one year, I dreaded having to mix 400 lbs of soil and just said "F it" too much effort.

putting a soil mix together isn't really all that hard once you understand WHY things work and why they don't.

Basically, anything with a 3 mm ish particle that is mostly inert (won't bleed or leach undesirable stuff when wet) durable (keeps its shape for years even after being frozen if that's where you live), porous (to capture and retain water and fertilizer and release it over time) combined with an other "sharp" ingredient (pool filter sand works wonders), and if you're looking for organic components, something that's reasonably chunky and mostly durable (sifted pine bark and/or the smallest orchid bark work very well).

There are alternatives (crushed brick is one --and it comes already crushed, or you can ask to sift through brickyard waste. crushed granite can work too--it's HEAVY)...but experimenting can be a problem and finding all those alternatives is time-consuming. the hassle is getting all that stuff in one place, then storing it for long term, then combining it when needed (I used big plastic drums, lifting and spinning----ssoooooo much lifting and spinning and scooping). Also, dealing with the mess all this creates (breathing the dust from all those durable, sharp particles can eventually kill you if you don't wear a mask) . Making your own pays if you have more than a dozen trees, but it will wear you out. Some clubs have soil parties where they gather and mix soil in bulk and sell it to members--do that if you can. It pays in time and effort.

 

[dbonsaiw]

Basically, anything with a 3 mm ish particle that is mostly inert (won't bleed or leach undesirable stuff when wet) durable (keeps its shape for years even after being frozen if that's where you live), porous (to capture and retain water and fertilizer and release it over time) combined with an other "sharp" ingredient (pool filter sand works wonders), and if you're looking for organic components, something that's reasonably chunky and mostly durable (sifted pine bark and/or the smallest orchid bark work very well).

I think this post should be embedded into all soil war threads. KIS - keep it simple. The principles are much more important than a list of specific substrates.

 

[VAFisher]

I'm still making my own. I buy the components from Amazon Prime so I don't have to pay for shipping. I have 25 trees right now and only a couple are what you would call big. Plus they all don't get repotted every year. I tend to mix about 5 gallons at a time when I need it over a few weekends. It can be beneficial for a smaller number of trees as well.

 

[ShadyStump]

Bringing things back to the OP's original thoughts, I'll try to break down my personal understanding into the basics.

Organic material in your soil is NOT necessarily bad.
It's dead matter that can rot, so it can contribute to root rot. It doesn't magically make all living roots rot; you need the right set of circumstances to get it rotting, largely meaning perpetually wet and lack of air.

Your pot is half the reason organic material can become problematic.
Small, shallow pots naturally don't like to drain as efficiently as deeper pots, but can also dry out faster, and there's less room for air to move around also. (It's a physics thing. Read up here for a deep dive) To compensate for these issues, we need a material in the shallow pot that drains easily, but doesn't dry out easily.
If you can find a well draining material that dries out too fast, you can mix in the right organic material to help compensate. If you find your soil is holding too much moisture, you can adjust your watering to compensate, or in some cases find the right material to open the soil up more. There are 1000 ways to compensate for less than ideal soil, and none of them are a magic bullet against disease.

Akadama is NOT the best thing out there.
The best thing out there is what works for you. If it's stupid but works, it isn't stupid. Unfortunately the only way to find what works for you is to experiment a little.
Akadama was what was discovered in Japan some time ago, and when Japanese masters traveled to teach they brought akadama with them and taught that, but that doesn't mean it's the only thing or even the best thing depending on your situation.

And we're back to this...

Basically, anything with a 3 mm ish particle that is mostly inert (won't bleed or leach undesirable stuff when wet) durable (keeps its shape for years even after being frozen if that's where you live), porous (to capture and retain water and fertilizer and release it over time) combined with an other "sharp" ingredient (pool filter sand works wonders), and if you're looking for organic components, something that's reasonably chunky and mostly durable (sifted pine bark and/or the smallest orchid bark work very well).

Don't over think it, and don't be lazy about it.