Water retention of akadama

[Joe Dupre']

This has always puzzled me about akadama. It's supposed to break down into smaller particles for the benefit of smaller and smaller feeder roots. I can see that. But, when the particles are that small, doesn't the pot hold water longer............almost too long? When the soil is that dense, does it drain much slower allowing the water to just build up on the surface? How about the air intake for the roots? Wouldn't it be harder for them to get air in such a dense medium?

 

[ZombieNick]

Yes, but when it breaks down to the point you are describing, it is time to repot. I feel like you already know this though, so perhaps I am missing your question?

 

[Joe Dupre']

Well, a lot of masters recommend fairly long repotting intermals..........5-10 years. I would think akadama might break down before that. When these masters repot, they leave the oldest, densest soil intact under the trunk, trim the outside roots and fill the outer perimeter with fresh akadama. Maybe the extra concentration of fine roots near the center allow for increased drainage and air uptake. Still kind of puzzling.

 

[Deep Sea Diver]

Both akadama and Kanuma percolate well when broken down. That’s also when the finest roots occur as the roots scale with the breakdown, tunneling in and around the particles, forming the Shin.

That’s why a tree can be kept in the pots long time. Also once a shin forms the tiny roots are mirrored by producing fine branching.

cheers
DSD sends

 

[Maiden69]

Both akadama and Kanuma percolate well when broken down. That’s also when the finest roots occur as the roots scale with the breakdown, tunneling in and around the particles, forming the Shin.

That’s why a tree can be kept in the pots long time. Also once a shin forms the tiny roots are mirrored by producing fine branching.

cheers
DSD sends

Also, people having some difficulties with akadama are in zones that have a lot of rainfall plus very cold temperatures, which will accelerate the breaking down of the particle. In zones 8+ akadama will last much longer.

 

[Joe Dupre']

Both akadama and Kanuma percolate well when broken down. That’s also when the finest roots occur as the roots scale with the breakdown, tunneling in and around the particles, forming the Shin.

That’s why a tree can be kept in the pots long time. Also once a shin forms the tiny roots are mirrored by producing fine branching.

cheers
DSD sends

If that's what happens, then it makes a lot more sense. A local, world-class bonsai grower says she's seen improvement in her trees since going to 15% akadama. My guess is she started there and will incorporate a higher percentage in the future.

 

[River's Edge]

they leave the oldest, densest soil intact under the trunk,

The akadama breaks down less in this area than the upper or outer areas. Often the particle size is retained the longest in this area and that is the reason why the core can be left longer. My experience has been that the akadama closest to the surface and the outer edges breaks down faster. With mature bonsai and advanced care the finer feeder roots do very well in the smaller particle size as the akadama breaks down.
Also, it is good to remember that the tree is watered when it needs it. So with experienced bonsai enthusiasts and trained masters the watering is adjusted as the media adjusts. If the moisture retention does increase this is factored into the care and maintenance of the tree.
Just my thoughts, from my experience.

 

[Maiden69]

My experience has been that the akadama closest to the surface and the outer edges breaks down faster.

Frank, do you have a Mirai account? This is something that Ryan states often, his solution... doing soji with the help of a vacuum cleaner. He cleans the top of th esoil until he reaches the area where he finds intact akadama, then top it all off with fresh particles. Doing so allows him to keep trees in akadama well past 5+ years.

I think he gives credit to Kimura for that, also to point out that Kimura's juniper Toryu-no-Mai has not being repotted since Kimura created it 35+ years ago. Don't know if it is due to the soji technique, but that is impressive to say the least.

 

[rockm]

Soji

Summer Soji - Bonsai Tonight

Summer is not the most interesting time of year in the bonsai calendar. The trees rarely look their best, and it's too hot for them to grow much. They do,

bonsaitonight.com

 

[Deep Sea Diver]

Also, people having some difficulties with akadama are in zones that have a lot of rainfall

Don’t see a lot of rainfall as a big deteriorating issue here if a tree has been properly mossed up. Sort of like a shock absorber the moss appears to soften the problem. Heat, drying the surface, definitely appears to be a issue.

Yet, especially on fine rooted plants, like maples (akadama) and very fine rooted azaleas (Kanuma) there is a large mechanical breakdown component to this issue.

plus very cold temperatures, which will accelerate the breaking down of the particle. In zones 8+ akadama will last much longer.

Been pondering the issue of very cold temperature breakdown for a number of years now, observing professionals winter/summer storage/display procedures etc. At this point I’ve come to the conclusion one must understand and respect the physical characteristics and limitations of the media one is using.

This means to me that if one wants to use akadama/Kanuma based media, the hobbyist must understand it needs to be properly protected and serviced to get the best effect from its use.

cheers
DSD sends

 

[August44]

Here we go again...I have a tree where the soil (33% akadama) has been in place for three years. I would say the the akadame is now what I would call granules the size of medium sand from the top to the bottom of the pot, and it's been that way since the first winter. If I put some between my fingers and rub them together, it is instantly red mud. I really don't know if that's good or bad but do know that one really has to watch how the tree is watered as the soil retains way more moisture that average soils and it could be easily over-watered.

Is akadama heated/baked now? We used to have just akadame. Now they are calling some "HARD" akadama. Does that mean they cooked it so it was harder and will not break down like it used to? So if I have cooked (hard) akadama and it doesn't break down is it still a good product for bonsai?

 

[Deep Sea Diver]

There are three grades of Akadama…. I use double or triple line types except for deciduous and water loving trees. It can be somewhat ‘wrought with danger’ when a hobbyist just asks for akadama. Understanding different brands can be a minefield as manufacturers change.

Here’s some info on each:

Depending on the quality of the Akadama bonsai soil (soft and hard) it should be replaced after 3-5 years. (This is a generalization ed note)

Akadama soft quality, Single line brand: Japanese 上質, Jōshitsu. Structural stability for up to 3 years. Can be used for bonsai trees that are frequently repotted (deciduous trees with strong root growth like Fig tree bonsai, Chinese elm bonsai, Japanese maple bonsai, but also other plants such as flowers).

Akadama hard quality, Double line brand: Japanese 硬質, Kōshitsu. Is structurally stable for longer time (4-5 years). Akadama hard quality should be taken if the bonsai remains longer than 3 years without repotting in the bonsai pots. This is especially true for older bonsai.

Akadama extra hard quality, Triple line Brand: Japanese 赤玉土. The Akadama brand with the 3 lines is broken down from slightly deeper layers, heated at 250-300°C after processing and is therefore the longest structurally stable kind of Akadama.

- DSD note when recycling Akadama media I use 450F… kind of a compromise between double and triple line. It retains the integrity of the particles without getting Uber hard.

Cheers
DSD sends

 

[Maiden69]

Don’t see a lot of rainfall as a big deteriorating issue here if a tree has been properly mossed up. Sort of like a shock absorber the moss appears to soften the problem.

I can't grow moss on my trees to save my life... I had a little moss appear on the north facing side of my house, only during winter/early spring, as soon as the heats comes in it is done.

Been pondering the issue of very cold temperature breakdown for a number of years now, observing professionals winter/summer storage/display procedures etc. At this point I’ve come to the conclusion one must understand and respect the physical characteristics and limitations of the media one is using.

This means to me that if one wants to use akadama/Kanuma based media, the hobbyist must understand it needs to be properly protected and serviced to get the best effect from its use.

This is the key, not a lot of people are willing to go through hoops and loops to do this. Serious artists do all the time, but those with time constraints, other jobs, life in the way rarely take the steps needed to maintain the water/oxygen balance needed to grow trees in akadama on those climates. Hell, if I was on a zone 6< I would probably wouldn't be using it, as I have no time during the day to properly water my trees... they are under an automated system. I'm already pulling the little bit of hair I got left thinking about when my trees enter into refinement... how am I going to be able to do pinching buds, checking pots for water balance, etc. Now all is peachy with everything in development.

 

[Clicio]

I've got two pines in Akadama - double line hardness - here in Brazil for three years now. They are doing fine and the Akadama is still holding, didn't turn into mush at all.
Watering per need and per season is a must though.

 

[August44]

I've got two pines in Akadama - double line hardness - here in Brazil for three years now. They are doing fine and the Akadama is still holding, didn't turn into mush at all.
Watering per need and per season is a must though.

Do your pots freeze there Clicio? I think us folks in freezing temp zones probably should not expect any akadama to say together with a freeze/thaw, freeze/thaw situation.

 

[August44]

There are three grades of Akadama…. I use double or triple line types except for deciduous and water loving trees. It can be somewhat ‘wrought with danger’ when a hobbyist just asks for akadama. Understanding different brands can be a minefield as manufacturers change.

Here’s some info on each:

Depending on the quality of the Akadama bonsai soil (soft and hard) it should be replaced after 3-5 years. (This is a generalization ed note)

Akadama soft quality, Single line brand: Japanese 上質, Jōshitsu. Structural stability for up to 3 years. Can be used for bonsai trees that are frequently repotted (deciduous trees with strong root growth like Fig tree bonsai, Chinese elm bonsai, Japanese maple bonsai, but also other plants such as flowers).

Akadama hard quality, Double line brand: Japanese 硬質, Kōshitsu. Is structurally stable for longer time (4-5 years). Akadama hard quality should be taken if the bonsai remains longer than 3 years without repotting in the bonsai pots. This is especially true for older bonsai.

Akadama extra hard quality, Triple line Brand: Japanese 赤玉土. The Akadama brand with the 3 lines is broken down from slightly deeper layers, heated at 250-300°C after processing and is therefore the longest structurally stable kind of Akadama.

- DSD note when recycling Akadama media I use 450F… kind of a compromise between double and triple line. It retains the integrity of the particles without getting Uber hard.

Cheers
DSD sends

Great info...thanks!

 

[Clicio]

Do your pots freeze there Clicio? I think us folks in freezing temp zones probably should not expect any akadama to say together with a freeze/thaw, freeze/thaw situation.

No.
It gets cold, but maybe only one or two frosts a year, nothing more than that.

 

[River's Edge]

Frank, do you have a Mirai account? This is something that Ryan states often, his solution... doing soji with the help of a vacuum cleaner. He cleans the top of th esoil until he reaches the area where he finds intact akadama, then top it all off with fresh particles. Doing so allows him to keep trees in akadama well past 5+ years.

I think he gives credit to Kimura for that, also to point out that Kimura's juniper Toryu-no-Mai has not being repotted since Kimura created it 35+ years ago. Don't know if it is due to the soji technique, but that is impressive to say the least.
View attachment 483631

No I do not have a Mirai account. Soji is a common practice for me, old school, no vacuum. Just the hand method taught by most Japanese masters. My climate has the tendency to freeze, thaw a bit so Soji is even more important. Also I use organic fertilizer both in tea bag and crumble on the surface. This also tends to increase the need for Soji.

 

[Deep Sea Diver]

Yep, we do it too at home and on the trees where we volunteer as a matter of routine. Just the pollen and dust falling from the sky and accumulating in Puget Sound region, let alone fertilizer, is enough to clog the soil in a year or two.

Not discounting Mr Neal at all….. yet not sure soji extends repotting repot timing . It just keeps the media permeable through the the normal period until the root growth gets such that a repotting is indicated …by avoiding the factor of impermeable media as a triggering factor for an early repot.

soji should also be done to non akadama medias. These medi clog from dust, pollen, organic media and what not too.

btw as an oceangoing sailor for many of 21 years, I’ve often heard the term Soji applied to what some folks call “a white tornado” It’s when we “scrub the ship down fore and aft!“. Never connected it to bonsai until I got into the hobby.

Happy Friday!
DSD sends

 

[August44]

There are three grades of Akadama…. I use double or triple line types except for deciduous and water loving trees. It can be somewhat ‘wrought with danger’ when a hobbyist just asks for akadama. Understanding different brands can be a minefield as manufacturers change.

Here’s some info on each:

Depending on the quality of the Akadama bonsai soil (soft and hard) it should be replaced after 3-5 years. (This is a generalization ed note)

Akadama soft quality, Single line brand: Japanese 上質, Jōshitsu. Structural stability for up to 3 years. Can be used for bonsai trees that are frequently repotted (deciduous trees with strong root growth like Fig tree bonsai, Chinese elm bonsai, Japanese maple bonsai, but also other plants such as flowers).

Akadama hard quality, Double line brand: Japanese 硬質, Kōshitsu. Is structurally stable for longer time (4-5 years). Akadama hard quality should be taken if the bonsai remains longer than 3 years without repotting in the bonsai pots. This is especially true for older bonsai.

Akadama extra hard quality, Triple line Brand: Japanese 赤玉土. The Akadama brand with the 3 lines is broken down from slightly deeper layers, heated at 250-300°C after processing and is therefore the longest structurally stable kind of Akadama.

- DSD note when recycling Akadama media I use 450F… kind of a compromise between double and triple line. It retains the integrity of the particles without getting Uber hard.

Cheers
DSD sends

DSD...Just so I understand, would you speculate that I am going to have the problem as pictured above with any akadama in my zone if the pot/tree are left exposed to the elements? If I will, is there any reason that I should even use it?