Sharp
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Can you expand why well draining soil is better soil for bonsai? I know that sounds very noobish of me to ask but I've yet to see a good reason for it.

Does it avoid root rot? I know if you have a heavier soil the water and moisture will stay longer, but wouldnt that just mean you water it less?

Im a novice when it comes to soil.

thanks in advance for any replies. :)

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Gnome
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Sharp,

Tree roots require both oxygen and moisture to thrive. A coarse soil that dries on a daily basis will obviously require watering on a daily basis. What may not be so obvious is that when you water a tree growing in coarse soil a fresh charge of air is drawn into the pot as the water drains away.

Secondly, growing our trees in shallow wide pots, as we do in bonsai culture, tends to maintain the level of water in the pot higher, relatively speaking, than if we were using tall narrow pots. In other words shallow pots don't drain as readily as taller pots.

So you can see that by using large sized particles we ensure not only proper drainage but the proper aeration neccessary for optimum growth.

These concepts are discussed in more detail here.

[url]https://www.evergreengardenworks.com/earthpot.htm[/url]

Here is a page of links, including the one above, regarding bonsai soils.

[url]https://www.fourseasonsbonsai.org/allthereis/soil.htm[/url]

I hope this begins to answer some of your questions.

Norm

Petra26
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Location: Chicago, IL

Gnome wrote:Sharp,

Tree roots require both oxygen and moisture to thrive. A coarse soil that dries on a daily basis will obviously require watering on a daily basis. What may not be so obvious is that when you water a tree growing in coarse soil a fresh charge of air is drawn into the pot as the water drains away.

Secondly, growing our trees in shallow wide pots, as we do in bonsai culture, tends to maintain the level of water in the pot higher, relatively speaking, than if we were using tall narrow pots. In other words shallow pots don't drain as readily as taller pots.

So you can see that by using large sized particles we ensure not only proper drainage but the proper aeration neccessary for optimum growth.

These concepts are discussed in more detail here.

[url]https://www.evergreengardenworks.com/earthpot.htm[/url]

Here is a page of links, including the one above, regarding bonsai soils.

[url]https://www.fourseasonsbonsai.org/allthereis/soil.htm[/url]

I hope this begins to answer some of your questions.

Norm
very cool, i did not know that. norm, great explanation as normal :D

ynot
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Thank you webmaster! :)

Sharp wrote:Can you expand why well draining soil is better soil for bonsai? I know that sounds very noobish of me to ask but I've yet to see a good reason for it.

Im a novice when it comes to soil.
Gnome has posted some excellent links above, I have allways found Brent Walston to be a goldmine of well articulated easilly digested information. :D
Gnome wrote:Tree roots require both oxygen and moisture to thrive.
Gnome has hit it right on the head here. [And as allways he is more succinct than I.:)]

You may have heard the term 'Drowning the plant'? it would be more accurate to say 'Suffocating the plant'.

Consider hydroponic or water gardening for a moment.[Plants grown in water.]
They survive because their enviroment [water] is manipulated to provide them with all they require. IE: Oxygen, Nutrients, ect. [More on this in a moment.]

A free draining soil consisting of larger particle sizes allows more space for oxygen/air between the particles. This proper mix of moisture/oxygen and loose structure promotes the growth of the fine white feeder hair roots that actually feed and sustain your tree.
Having that healthy feeder root mass is a key component to a trees survival in the small/shallow pots used for bonsai.

In a soil that contains 'fines' [Small particles] there is a lack of airspaces due to the smaller particles filling in all the available spaces between the larger ones. This 'smaller sized soil' will compact/breakdown quickly as well which will only further reduce the available airspaces within the soil.
Removing these smaller particle sizes via sifting means that there are now many tiny airspaces within the soil.

When your soil has alot of 'fines' in it, [That would be an example of NOT well draining soil.] There is no room for the required gaseous exchanges to take place [Part of the function of the root system]. This lack of airspaces within the soil can lead to an allways wet condition and eventually roots damaged so badly they can neither take in water or oxygen. Subsequently It is a lack of moisture and oxygen that kills the tree.
Keep in mind that this usually happens while growing in a soil that retains water quite well.
Which do you think the tree was failing to get it's daily requirements of?

It is not semantics, Note that hydroponicly grown plants don't drowned despite the fact their root systems are submerged.
This is because the water they grow in is oxygen enriched [IE: DWC] so they do not suffocate.

A looser soil mixture helps to draw more [airborn] oxygen into the pot during drainage while watering, Air contains far more oxygen than water.

A looser well draining mix helps your tree meet its requirements better than a less aerated mix which does not have as much oxygen available,
After all a tree can only grow an amount equivilant to the amount of the least available resource required for growth.
Sharp wrote:Does it avoid root rot? I know if you have a heavier soil the water and moisture will stay longer, but wouldnt that just mean you water it less?
As stated above, It is not about the watering schedule. It is about what you are actually providing for your tree.
This is why I say in the soil sticky:
ynot wrote:This is why it is important to understand the function of your soil wrt its components.
If you want to water less often simply use a more organic mixture as it will retain more moisture, The large particle size is what facilitates the drainage aspect of your soil.
A looser soil structure helps it get the oxygen it requires into the soil and helping to insure it's health as well by not promoting the conditions for root rot.
Root rot is a fungus and while I can't say it will prevent it, [As all things are possible] A well draining soil will help prevent you from having the types of conditons that fungi thrive in.
From The Ag college plant pathology extention at NCSU

[Emphasis mine]
Factors Favoring Disease Occurrence

Phytophthora root rot is favored by high soil moisture and warm soil temperatures.The disease does not occur as frequently and may not be as severe on well-drained sandy soils as in heavy clays or poorly drained soils, etc.
The disease is common and severe in areas where run-off water, rain water from roofs, etc. collects around plant roots. Shallow soils with underlying rock or compacted hard pans, setting woody plants deeper than the soil level in the nursery or container, over-watering plants, or long periods of heavy rain also favor disease development
Source= https://www.ces.ncsu.edu/depts/pp/notes/oldnotes/odin13/od13.htm
I know this has been an extremely repetitive post...lol. I want this point to sink in. [Your trees will thank you! 8)] :D
Hope this helps a bit.
ynot

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Gnome
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Petra wrote:
norm, great explanation as normal
Ynot wrote:
Gnome has hit it right on the head here. [And as allways he is more succinct than I.]
Thank you both very much. Ynot, sometimes more IS more.

Norm

ynot
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Gnome wrote:. Ynot, sometimes more IS more.
Norm
:lol: ...Yep, And on a completely related note:

Sharp,
I found a couple of pictures that sort of demonstrate the benefits of a larger particle soil... In my experience.

This is one example of why you will hear me 'beat the Proper soil drum' often and loudly.
[IMO If more people were informed {or applied the info} on this issue and the fallacy of the effectiveness of 'Watering on a schedule' {Don't even get me started :!: } there would be alot less sick bonsai.]

Anyway, on to the pictures:

August 11, 05 I was bored with this 14" Ficus benjamina which was essentially taking up space in a pot, No taper, No prospects, No potential...etc.

[img]https://i7.photobucket.com/albums/y291/novusordo1/Ficus/Raft%20Ficus/Pre-Raft/FicusBenj2.jpg[/img]

Later that day I chopped the top off of it, Just above the lowest branch.

[img]https://i7.photobucket.com/albums/y291/novusordo1/Ficus/Raft%20Ficus/raftdonor.jpg[/img]

After removing all the branches from one side of the top and wiring a few others away from the 'bald side',
I also gave it a sprinkle of rooting hormone as you can see from the picture.

August 12th, Remember, There are no roots at all on it at this point. It was the top of the tree.

[img]https://i7.photobucket.com/albums/y291/novusordo1/Ficus/Raft%20Ficus/raft1.jpg[/img]

I then planted it into a nice free draining large particle mix.
[Raft style, Where it looks as though a tree fell in the forest and the trunk rooted and the branches became trees themselves.]

[img]https://i7.photobucket.com/albums/y291/novusordo1/Ficus/Raft%20Ficus/raft6.jpg[/img]

The next three pictures were taken 9 days later on August 23, 05.

[img]https://i7.photobucket.com/albums/y291/novusordo1/Ficus/Raft%20Ficus/Raftroots12_07.jpg[/img]
[img]https://i7.photobucket.com/albums/y291/novusordo1/Ficus/Raft%20Ficus/Raftroots12_05.jpg[/img]
[img]https://i7.photobucket.com/albums/y291/novusordo1/Ficus/Raft%20Ficus/Raftroots12_04.jpg[/img]

When I wired the branches I knew I would eventually have to disturb the planting to remove them. I didn't know it would be so soon. 8)

This is September 5, 05:
24 days after I planted it with no root system whatsoever.

[img]https://i7.photobucket.com/albums/y291/novusordo1/Ficus/Raft%20Ficus/RaftRootage.jpg[/img]

Here is the raft as it looked at the beginning of October 06, 10" high from the soil.

[img]https://img515.imageshack.us/img515/6638/ficusraftoct060003to0.jpg[/img]

Full disclosure: :wink:
Feel free to stop by this link and click on the photos that I posted to check the Exif Data which contains all the camera information.
IE: The date of the photo, Exposure, etc...[The Exif Data is just below each picture after you open it.]

https://s7.photobucket.com/albums/y291/novusordo1/Ficus/Raft%20Ficus/

Just thought I would share a bit of how arrived at my opinion about soil :D.

Actually I allready had this viewpoint even then but it did reinforce it.:lol:

In my experience the results speak for themselves, Your mileage may vary. 8)

ynot

ps- In case your wondering what happened to the bottom half of the tree. [Remember the second picture of this post?]

Here it is 9 months later, 7" high from the soil which is about the same size as your toothbrush. 8)

[img]https://img224.imageshack.us/img224/9048/6693ficusbadvicepleaseficusshohinmay060002yp5.jpg[/img]

If interested, The step by step of this one is at https://www.helpfulgardener.com/forum/viewtopic.php?p=18379#18379

Sharp
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Joined: Sun Aug 14, 2005 12:42 pm

Perfect, thanks everybody!!


(sorry about the double post, i completely missed this one and based on a convo ealier with Ynot i was gonna remake) :)



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