BaKiBonsai
Yamadori
It was clear, just coincidentally had some floating pumice. It looks a bit different from my regular pumice. Size is about 8-16mm. Pointy finger for scale
The Bonsai Soil Argument
- Thread starter Attmos
- Start date
Bonsai Nut
Nuttier than your average Nut
Here's what mine looks like...
The old grower questions...
How do you have a media with water holding capacity and high aeration?
What media is best for plants I am producing?
How do I make a media that I can afford?
Perhaps there is a misconception of what the "nursery" industry really is, at least in the US. There is a huge difference between the floriculture segment and the landscape nursery segment with many sub segments as well.
Commercial floriculture growers (potted plants and bedding) use lots of organics (peat or coco) with perlite or similar. These plants rarely end up on your bonsai benches or in the landscape. Landscape nurseries use lots of organics - mostly some sort of locally acquired aged bark. These plants are destined for the landscape with endless types of native soils. My county has over 125 different soils.
I guess the other main factors are watering preferences and the contain size, shape and material.
To generalize" tall pot= faster drainage, short pot=slower drainage.
Water every day more than once or every few days, thats up to you as well.
Take home message is there is no one magic media to fit your specific location or growing techniques. You either figure out someone else's or you make your own that works for you.
This is a quote from the Cornell article posted below, bold is my edit:
"In conclusion, we might say that the mixes are not destined to result in the elimination of soil as a growing media. They will not make a poor grower a good grower, nor are they a panacea for all of the growers production ills."
Peat-lite (from Cornell) was one of the main reason crops were able to be grown without "real soil" and plastic pots.
UC (UC Davis and Riverside) developed their own mixes designed for various crops and California.
How do you have a media with water holding capacity and high aeration?
What media is best for plants I am producing?
How do I make a media that I can afford?
Perhaps there is a misconception of what the "nursery" industry really is, at least in the US. There is a huge difference between the floriculture segment and the landscape nursery segment with many sub segments as well.
Commercial floriculture growers (potted plants and bedding) use lots of organics (peat or coco) with perlite or similar. These plants rarely end up on your bonsai benches or in the landscape. Landscape nurseries use lots of organics - mostly some sort of locally acquired aged bark. These plants are destined for the landscape with endless types of native soils. My county has over 125 different soils.
I guess the other main factors are watering preferences and the contain size, shape and material.
To generalize" tall pot= faster drainage, short pot=slower drainage.
Water every day more than once or every few days, thats up to you as well.
Take home message is there is no one magic media to fit your specific location or growing techniques. You either figure out someone else's or you make your own that works for you.
This is a quote from the Cornell article posted below, bold is my edit:
"In conclusion, we might say that the mixes are not destined to result in the elimination of soil as a growing media. They will not make a poor grower a good grower, nor are they a panacea for all of the growers production ills."
Peat-lite (from Cornell) was one of the main reason crops were able to be grown without "real soil" and plastic pots.
UC (UC Davis and Riverside) developed their own mixes designed for various crops and California.
Attmos
Chumono
Good luck with your trees.
Attmos
Chumono
I think the core difference between volcanic substrate types is the density and porosity. Each type is mined for it's particular makeup... some has little density and large air-pockets, some is more dense with smaller air-pockets.
Anyway, we all know lava rock floats if there are enough large, closed air pockets in the piece; and I think that might be why these tiny bits don't float much. The stone/glass has been broken down to the point that there aren't enough closed air pockets to keep the piece afloat. Just a guess though, I haven't done any specific reading on it.
Attmos
Chumono
In the resources section of this site, there are a few science based explanations of soil and how different types react to water, air, and nutrients.
rockm
Spuds Moyogi
It depends on the source of the lava rock. Volcanic rocks are not all the same. Some are “fluffier” than others. What you’re assuming as lava rock for soil is may not be what many are using.I think the core difference between volcanic substrate types is the density and porosity. Each type is mined for it's particular makeup... some has little density and large air-pockets, some is more dense with smaller air-pockets.
Anyway, we all know lava rock floats if there are enough large, closed air pockets in the piece; and I think that might be why these tiny bits don't float much. The stone/glass has been broken down to the point that there aren't enough closed air pockets to keep the piece afloat. Just a guess though, I haven't done any specific reading on it.
Attmos
Chumono
Right.
BaKiBonsai
Yamadori
And my German brand. I have to dry it before I sift it some more, quite the chore.
Attachments
Bonsai Nut
Nuttier than your average Nut
It is embarrassing for me to say that it is cheaper for me to buy pumice from Japan that it is for me to buy pumice from domestic sources here in the US. At any rate, I buy Hyuga pumice and it is very clean and lightweight. I can buy an 18liter bag locally for for about $32... though I get quantity discounts.
Jrmcmich
Chumono
Just recently got exact same kind from local bonsai supplier not too far from me. Other pumice I got through Amazon and other online bonsai supply was a bit larger particle size and white color.
BaKiBonsai
Yamadori
The German brand was €19 for 30L unsifted. Did get some fines but you don't see it in the volume. I can buy a big bag (1000L) for €150, but no space for it.
Not even tried.
Nobody asked you also. That's what happens in a forum.
Leo in N E Illinois
The Professor
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I used to buy a brand of pumice called "Dry Stall", which had a very fine particle size. It matched perfectly with the particle size of the Diatomaceous Earth (DE) of NAPA 8822. The 2 mixed made a nice mix for shohin and other small potted plants. For larger trees, kifu and above I use a more coarse brand of pumice I get through Ron F of Ancient Arts Bonsai, a Wisconsin vendor that I got to know through the Milwaukee Bonsai society. Ron also carries a DE with a more coarse particle size than the Napa 8822, that matches the particle size of the pumice he sells. This is important, when you make your own mix, particle size should be as uniform as possible.
Currently, for most conifers, I use at least 50% pumice, with the rest being akadama, and either DE or fir bark or lava, depending on whether I want more or less moisture holding. More water holding, more akadama, less water holding, more lava.
Currently, for most conifers, I use at least 50% pumice, with the rest being akadama, and either DE or fir bark or lava, depending on whether I want more or less moisture holding. More water holding, more akadama, less water holding, more lava.
Wulfskaar
Masterpiece
A couple years ago, I got 3 white willow sticks as a gift. I'd add those to bald cypress.
2 are in potting soil and 1 is in bonsai soil. The 2 in potting soil have outgrown the one in the bonsai soil by 3 or 4 times.
So yeah, white willows also love potting soil as far as I can tell. I believe it's because they are water-loving trees, like BC.
Glaucus
Omono
I have been on this forum for almost 20 years. You literally added nothing and are trolling and being toxic for no reason.
You are way out of line!
I have tons of patience with people that make incorrect reasoning or false arguments. I have zero tolerance for people that just want to push ignorance and be pricks.
You literally made no post on this forum ever that is more than 3 sentences.
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Leo in N E Illinois
The Professor
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Particle Size
The aspect of media does not get the emphasis it deserves. It is very important to strive for a near uniform particle size. If particle size is uniform, the soil media can breathe, allowing air to penetrate bringing oxygen to the roots. If your media has a wide range of particle sizes, the media will settle and compact, leaving little or no voids for air penetration an water movement.
This issue is independent of the type of media. ALL bonsai potting mixes are vastly improved by using a sieve to eliminate fines and excessive large chunks. Get rid of the "dust". If you do not have a purpose made set of bonsai media sieves, you can at least get rid of fines using a piece of window screen used to keep mosquitos out of the house. Amy media that goes through the window screen should be discarded as too fine to use in a pot. It can be added to the vegetable garden, earthworms and other creatures will consolidate it into the garden loam.
So no matter what media types you choose, use a sieve to eliminate fines, and if the range of sizes is more large, a screen to eliminate "big chunks" too.
Most bonsai media sieves have 3 screens, allowing you to make 2 grades of media, a small for mame and shohin , and a medium for larger trees, the 3rd screen is the one to eliminate large chunks, too large for either category of media.
Sift all components while dry. I tend to sift components separately as I make up my mixes. But I often sieve again after I have combined all my components, because for some reason, there always seems to be a large amount of dust and fines generated by the act of mixing. Whether mixing is just "knocking loose" fines stuck to larger particles or whether pumice and such are breaking up as I mix, I don't know, but sifting more than once seems prudent.
The resulting media will be very free draining, allowing good water penetration and air penetration, you will enjoy working with the finished media.
The aspect of media does not get the emphasis it deserves. It is very important to strive for a near uniform particle size. If particle size is uniform, the soil media can breathe, allowing air to penetrate bringing oxygen to the roots. If your media has a wide range of particle sizes, the media will settle and compact, leaving little or no voids for air penetration an water movement.
This issue is independent of the type of media. ALL bonsai potting mixes are vastly improved by using a sieve to eliminate fines and excessive large chunks. Get rid of the "dust". If you do not have a purpose made set of bonsai media sieves, you can at least get rid of fines using a piece of window screen used to keep mosquitos out of the house. Amy media that goes through the window screen should be discarded as too fine to use in a pot. It can be added to the vegetable garden, earthworms and other creatures will consolidate it into the garden loam.
So no matter what media types you choose, use a sieve to eliminate fines, and if the range of sizes is more large, a screen to eliminate "big chunks" too.
Most bonsai media sieves have 3 screens, allowing you to make 2 grades of media, a small for mame and shohin , and a medium for larger trees, the 3rd screen is the one to eliminate large chunks, too large for either category of media.
Sift all components while dry. I tend to sift components separately as I make up my mixes. But I often sieve again after I have combined all my components, because for some reason, there always seems to be a large amount of dust and fines generated by the act of mixing. Whether mixing is just "knocking loose" fines stuck to larger particles or whether pumice and such are breaking up as I mix, I don't know, but sifting more than once seems prudent.
The resulting media will be very free draining, allowing good water penetration and air penetration, you will enjoy working with the finished media.
Brain Treez
Mame
My choice to never use akadama is rooted (
) in consideration of its carbon footprint. I'm not paying to have some diesel mega-container-ship chug across the Pacific ocean to bring me some dirt. We are each obviously free to decide based on whatever parameters we prioritize.
Yes, I am aware reducing the demand for akadama by a single bag won't "make a difference" but we can each only do what we can do and control what we can control.
) in consideration of its carbon footprint. I'm not paying to have some diesel mega-container-ship chug across the Pacific ocean to bring me some dirt. We are each obviously free to decide based on whatever parameters we prioritize.Yes, I am aware reducing the demand for akadama by a single bag won't "make a difference" but we can each only do what we can do and control what we can control.
Bonsai Nut
Nuttier than your average Nut
I don't disagree. I live in North Carolina, the home of iron-rich clay soil. Why can't I get tumbled, fired clay product like akadama? It isn't from lack of me trying to find a source. The closest I have come to is "Statesville Brick" and their brick fines.My choice to never use akadama is rooted (
There is a local company that makes fireplaces using Icelandic pumice. They bring it in by the boatload (literally) to the East Coast. I have contacted them several times about buying pumice from them in bulk... and they always say "we already sell horticultural pumice - and send me a link for quart bags at $14.99 each.
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