Potting Mix Tests Results Abbreviated
Posted: August 11th, 2010, 3:36 pm
Hi Everyone,
Here are the abbreviated results in a PDF. Just click on the file and save to somewhere; then you can view it.
.
Soil Mix Component Test Results. (Components only!)
I thought I would use Akadama and Kanuma as a known reference point to start with. The reason being that Kanuma and Akadama have been tried, tested and used by the Japanese for a long time and so the properties/performance of the component/soil on its own is known for both Akadama and Kanuma. This may not be directly comparable but it is a start. Kanuma is used 100% on its own for Azalaeas and Akadama can be used on its own for a wide range of plants. Akadama can also be used in blends of components to create your own tailored mix.
I am not advocating that Akadama or Kanuma be your bonsai mix or part of your mix! I am just looking at how it performs and then comparing it to other materials that we can also readily source in Australia.
Proprietary Bonsai mixes made by the Bonsai nurseries and Debco, Amgrow etc are treated as a component or stand alone mix as well. I cannot say exactly what is in each blend and to a certain extent it is irrelevant as I am looking at its performance; not what it is made up of.
How I did it.
Firstly with Akadama and Kanuma, and some other products, you buy them in bags of a certain size. Names of sizes can be confusing so I have designated a particle size that is being used. I sieved out all dust that is .6mm in size and disposed of it. I then graded the rest into size ranges to find out what percentage has been wasted as dust and then what size particles are left.
Particle size and shape are important to its performance; weight not so important except to lighten mix.
I have sieves that give me + .6mm to -2mm, 2mm to -4mm, 4mm to -7mm and over 7mm(Approximate)
The test results below firstly show the performance of the component with all its sizes in the ratios found and put into the pot in layers in 5”/125mm pots. Coarsest part of the component on bottom, then middling coarse then smallest on top. With some components like the propagation sand/ 3mm brown pebble they are just used straight out of the bag.
I also tested each individual particle size’s performance as well, but there is too much info at this point. I can discuss the individual components and individual component’s particle sizes as we go on. It is important! Particle size is everything! (Well almost)
Each of the components behave differently in interesting ways and it is hard to describe. Some are very easy to dry; some are hard to dry; some behave very differently in small and large size particles; some not so much; some hardly at all.
Labels.
Medium/Component. Name of the component I am testing
KG Dry. How much a pot full of the dry component weighed. We then put in water to lip of pot to soak
KG Drained. After 10 minutes of soaking we then let drain for 10 mins then weighed.
Water Gain KG. Weight of water gained/held/absorbed after draining for 10 mins
(NOTE. Some components are very light and increase in weight dramatically when wet but still hold/gain/absorb the same amount as some other components; so we have not expressed water gain as a % of dry weight of the component!)
PH. I used the Manutec test kit, liquid then powder, and these are our results on the day. Please allow for some leeway.
Water Table. Amount of water that freely drained out of the component when it was tipped on its side after 60 mins. Expressed as grams although we could do % of KG
AFPT. Air Filled Porosity Test. Component was placed into an open top container (1 ltr) immersed into water; wet then water allowed to drain, captured and weighed. If 300 mls of water were captured it is expressed as 30% AFP
Results....
Well, what do we make of it all?
Firstly, Kanuma. A mix for Azaleas. I have always had a brown thumb when it came to Azalea but we now have a Satsuki azalea growing in 100% Kanuma at the collection and it is happy as Larry. I will probably grow all my Azalea at home and in the Collection in Kanuma from now on.
The difference in performance from my tests show that Kanuma and Akadama have same PH; same water table and similar Air Filled Porosity (at least on day one). Kanuma is lighter and absorbs/holds more water however.
Going by PH I definitely would not try Mt Sylvia Diatomite, Spongalite or Attapulgite on their own as a replacement for Kanuma. Maidenwell Diatomite is right PH but has lower water table, higher air filled porosity and higher water gain/ absorbing quality(which surprised me!) Worth trying? Yes in my opinion.
Perlite? Don’t know! But probably not practical.
Akadama. A general mix or component?
Moderate weight, moderate water gain/holding, slightly acid PH, low water table and moderately high Air filled porosity.
The folks in WA are using it in various ways and it seems to perform OK over there with extra water holding components added. It will compact over time I presume and lose some air filled porosity. I will be repotting 2 WA trees this year and will let you know how they look in the Akadama after a few years in WA and a few years here growing nicely.
My feeling is that most of the other components could compliment Akadama or replace the Akadama in Australia in most cases. In Japan they have a summer monsoon and the trees drain quick enough not to water log bonsai; they would tilt the tree to aid drainage if necessary. In Australia we can have hot, humid, wet summers; or hot, arid dry, no rain summers; or cool, dryish, dry summers; depending where you live.
Apparently it is no good in countries/ areas that have long, cold, wet winters as the Akadama turns to mush.
Unsurprisingly Crushed brick isn’t way wide of the mark.
Also Chinese Akadama behaves similar to Akadama but without as much water gain. As it is a hard, baked product I am not surprised.
By reputation alone Maidenwell Diatomite may be our equivalent to Akadama. It is light, gains/absorbs water, has a low water table, highish Air filled porosity and same PH or similar, and a nice brown color.
My growing trials will answer some of these questions.
I have more information on the performance of the various particle sizes in each product. Size of particle can slow or increase drainage as needed.
I will post separately and discuss separately,
Grant
Here are the abbreviated results in a PDF. Just click on the file and save to somewhere; then you can view it.
.
Soil Mix Component Test Results. (Components only!)
I thought I would use Akadama and Kanuma as a known reference point to start with. The reason being that Kanuma and Akadama have been tried, tested and used by the Japanese for a long time and so the properties/performance of the component/soil on its own is known for both Akadama and Kanuma. This may not be directly comparable but it is a start. Kanuma is used 100% on its own for Azalaeas and Akadama can be used on its own for a wide range of plants. Akadama can also be used in blends of components to create your own tailored mix.
I am not advocating that Akadama or Kanuma be your bonsai mix or part of your mix! I am just looking at how it performs and then comparing it to other materials that we can also readily source in Australia.
Proprietary Bonsai mixes made by the Bonsai nurseries and Debco, Amgrow etc are treated as a component or stand alone mix as well. I cannot say exactly what is in each blend and to a certain extent it is irrelevant as I am looking at its performance; not what it is made up of.
How I did it.
Firstly with Akadama and Kanuma, and some other products, you buy them in bags of a certain size. Names of sizes can be confusing so I have designated a particle size that is being used. I sieved out all dust that is .6mm in size and disposed of it. I then graded the rest into size ranges to find out what percentage has been wasted as dust and then what size particles are left.
Particle size and shape are important to its performance; weight not so important except to lighten mix.
I have sieves that give me + .6mm to -2mm, 2mm to -4mm, 4mm to -7mm and over 7mm(Approximate)
The test results below firstly show the performance of the component with all its sizes in the ratios found and put into the pot in layers in 5”/125mm pots. Coarsest part of the component on bottom, then middling coarse then smallest on top. With some components like the propagation sand/ 3mm brown pebble they are just used straight out of the bag.
I also tested each individual particle size’s performance as well, but there is too much info at this point. I can discuss the individual components and individual component’s particle sizes as we go on. It is important! Particle size is everything! (Well almost)
Each of the components behave differently in interesting ways and it is hard to describe. Some are very easy to dry; some are hard to dry; some behave very differently in small and large size particles; some not so much; some hardly at all.
Labels.
Medium/Component. Name of the component I am testing
KG Dry. How much a pot full of the dry component weighed. We then put in water to lip of pot to soak
KG Drained. After 10 minutes of soaking we then let drain for 10 mins then weighed.
Water Gain KG. Weight of water gained/held/absorbed after draining for 10 mins
(NOTE. Some components are very light and increase in weight dramatically when wet but still hold/gain/absorb the same amount as some other components; so we have not expressed water gain as a % of dry weight of the component!)
PH. I used the Manutec test kit, liquid then powder, and these are our results on the day. Please allow for some leeway.
Water Table. Amount of water that freely drained out of the component when it was tipped on its side after 60 mins. Expressed as grams although we could do % of KG
AFPT. Air Filled Porosity Test. Component was placed into an open top container (1 ltr) immersed into water; wet then water allowed to drain, captured and weighed. If 300 mls of water were captured it is expressed as 30% AFP
Results....
Well, what do we make of it all?
Firstly, Kanuma. A mix for Azaleas. I have always had a brown thumb when it came to Azalea but we now have a Satsuki azalea growing in 100% Kanuma at the collection and it is happy as Larry. I will probably grow all my Azalea at home and in the Collection in Kanuma from now on.
The difference in performance from my tests show that Kanuma and Akadama have same PH; same water table and similar Air Filled Porosity (at least on day one). Kanuma is lighter and absorbs/holds more water however.
Going by PH I definitely would not try Mt Sylvia Diatomite, Spongalite or Attapulgite on their own as a replacement for Kanuma. Maidenwell Diatomite is right PH but has lower water table, higher air filled porosity and higher water gain/ absorbing quality(which surprised me!) Worth trying? Yes in my opinion.
Perlite? Don’t know! But probably not practical.
Akadama. A general mix or component?
Moderate weight, moderate water gain/holding, slightly acid PH, low water table and moderately high Air filled porosity.
The folks in WA are using it in various ways and it seems to perform OK over there with extra water holding components added. It will compact over time I presume and lose some air filled porosity. I will be repotting 2 WA trees this year and will let you know how they look in the Akadama after a few years in WA and a few years here growing nicely.
My feeling is that most of the other components could compliment Akadama or replace the Akadama in Australia in most cases. In Japan they have a summer monsoon and the trees drain quick enough not to water log bonsai; they would tilt the tree to aid drainage if necessary. In Australia we can have hot, humid, wet summers; or hot, arid dry, no rain summers; or cool, dryish, dry summers; depending where you live.
Apparently it is no good in countries/ areas that have long, cold, wet winters as the Akadama turns to mush.
Unsurprisingly Crushed brick isn’t way wide of the mark.
Also Chinese Akadama behaves similar to Akadama but without as much water gain. As it is a hard, baked product I am not surprised.
By reputation alone Maidenwell Diatomite may be our equivalent to Akadama. It is light, gains/absorbs water, has a low water table, highish Air filled porosity and same PH or similar, and a nice brown color.
My growing trials will answer some of these questions.
I have more information on the performance of the various particle sizes in each product. Size of particle can slow or increase drainage as needed.
I will post separately and discuss separately,
Grant