Why do bonsai pots have large drainage holes ?

[Paradox]

Paradox, anderson tray & colanders ARE a vast improvement on the ancient bonsai pot designs. Welcome to air pruning, superior drainage & superior root aeration

First I am not new to air pruning. I use containers very much like colanders as training pots. They work fine but I also use pots with solid sides and they also work fine. I have not seen one difference or advantage of on over the other whatsoever.

We are talking about 2 different things.

An Anderson flat is used as training pot and it has solid sides and a mesh bottom, I would not consider it the same as a colander or similar that has holes on the side.

The the pot you posted in the first picture and the title of the thread asks about BONSAI pots which is different from a training pot.

Scott, I totally disagree with you. Good drainage & aeration starts with the pot. Soil comes later. Making fast draining soil is good but to put that into pots having poor drainage & aeration just seems like taking 1 step forward and 1 step backwards.

Scott is absolutely correct. You can put as many holes in the pot that you want, if the soil does not drain it doesnt matter one iota.

Here is a scots pine that I have had for 5 years. This picture was taken in 2012.



See the pot it is in? Exactly what you are talking about right?
However there is window screen lining the inside of the pot and the soil is a mixture of sand and gravel.
The bottom of the pot has several 3/8 inch holes for drainage. Being sand, the soil always drained pretty fast when I watered.

The tree was repotted from its nursery container to that pot in the spring of 2012.
The tree did ok. It grew some but wasnt extremely vigorous.

Fast forward to March 2016.
I repotted the tree into a shallow, plastic bonsai shaped training pot with a mixture of sifted lava, pumice, akadama, gravel and charcoal.
When I took it out of the sand and gravel, I noted that in 4 years there had been very little root growth. There was some but certainly not what I would expect after 4 years.



I put moss over the soil to help it retain a bit more moisture. I find the mix to dry out very quickly when it is new. I removed the moss in September.
Note: This training pot has a lot less holes than the old training pot.

Here is what I noticed when I removed the moss.
The tree went absolutely nuts with root growth. There were new roots everywhere.
The tree's branches had bulked up on wood to the point where one branch almost doubled in thickness.

So the tree went from a pot with more holes and a sand mix to a pot with less holes and a larger sized (about 1/4" inch) soil mix.

I have no doubt that the response I got from the tree has everything to do with the change in soil, not the change in the pot.
Ive seen similar results just by changing the soil and keeping the same pot as in the first picture.

 

[GGB]

If I used a pot with tons of 1/4" holes in it my soil would all fall out of it. Unless I used mesh across the entire inside, but at that rate I would just use a normal bonsai pot, and I do. But I guess if you're talking about huge pots that wouldn't apply

 

[jeanluc83]

@Bonsai Hunter It just seams like you are trying to solve a problem that doesn't really exist. I don't know that anyone has ever complained about how much they hate putting mesh over the holes in their pots.

 

[sorce]

But your debate is kind....
on track.
And we all have learned.

Excellent.

Sorce

 

[M. Frary]

@Bonsai Hunter It just seams like you are trying to solve a problem that doesn't really exist. I don't know that anyone has ever complained about how much they hate putting mesh over the holes in their pots.

I do. It kills me.

 

[Bonsai Hunter]

Frost proof ceramic bonsai pots, handmade by Pötscher Walter (Austrian guy, site in German)



http://www.bonsaischalen.at/walu-system-neu/ (use this to see pics. pics don't show up in translation page)

https://translate.google.co.in/translate?hl=en&sl=de&u=http://www.bonsaischalen.at/&prev=search

 

[Bonsai Hunter]

@Bonsai Hunter It just seams like you are trying to solve a problem that doesn't really exist. I don't know that anyone has ever complained about how much they hate putting mesh over the holes in their pots.

Apart from the clogging issue (which I would like to test out myself), the ceramic pots with multiple holes have better drainage, better aeration for roots & air pruning from below. And would eliminate the mesh nuisance totally. In my video of the 2 plastic bonsai pots, which one would you choose, if both costed the same ?

 

[Bonsai Hunter]

Hmm, well if you check the pots ability to drain before using. you can drill a hole where the water might be moving more slowly.
You can also take stainless steel mesh make a pot that fits into your - exhibition pot - for showing, you can just grow
in a metal container all of the time, but so much extra inventory.
Anthony

Thats a good idea too, as the base need not be level every time. I like your idea of dual pots, one for exhibition, one for growing.

 

[Bonsai Hunter]

Ceramic colanders don't face freezing. Small holes are more susceptible to freeze damage. Ceramics become much less strong with many holes. I can fire a stoneware pot with many small holes and one with regular holes and smash them but I doubt you'd believe me. It seems you are out to prove your point and justify your youtube video questioning "intelligent" pot design. What is apparent, regardless of your motives, is that you are unfamiliar with the physical qualities of the material you are concerned with.

I havent made any point so far. I am SEEKING info/opinion on a design aspect. On my youtube video too i have merely raised a question, seeking info/opinion. I do see shortcomings on the bonsai pot design and soon intend to give my take on it - in black and white, no grey areas, in my next video. I have already admitted I havent worked with ceramic pots but who in this forum has worked with a ceramic bonsai pot with multiple holes of the the type i illustrated ? Is there even one person ?

 

[Anthony]

@Bonsai Hunter,

the mesh idea is from the 50 - 60' s a chap who used to offer advice and sales of bonsai.
He folded screens to make rectangular pots.

Which today would be the colanders. We get the colanders from India as stainless steel rice strainers.

We have written to Air-pots for some additional information, if they respond, I will place the information
here.

Are you able to grow Tamarinds ? or Gmelina or Serissas ?

Would like to see your results with those.
Enjoying your curiosity.
Good Day
Anthony

* We also make pots, vitreous and porous, but have never had a problem with drainage or soils.

 

[Bonsai Hunter]

"Good drainage" starts and ends with the soil. The size, shape, or number of drainage holes is close to irrelevant. Water needs a hole to get out. That's pretty much it.
Scott

In that case, please tell me why do bonsai pots have HUGE drainage holes ? They should all have just 1 hole as wide as your finger, covered with a mesh screen, isn't it. Why have 2, 4, 6 or 8 holes ? And why use a extremely fast draining and expensive Akadama soil imported all the way from Japan ? Why not use the locally available bonsai soil mix ? See the contradiction ?

Scott, I do agree soil needs good drainage & aeration. I also understand water table. When i tilt my pot i see it. What you seem to be ignoring is that good pot drainage = good aeration for roots. In my video of the 2 plastic bonsai pots, which one would you choose, if both costed the same ? I mentioned poor drainage, poor aeration & zero air pruning. Do you deny all 3 ?

 

[Bonsai Hunter]

Has anyone tried out this pot design by Peter Bone, a forum member here ? It certainly looks like a vast improvement to me over the ancient bonsai pot designs. Maybe not for exhibition but for the rest of the time.



http://www.shapeways.com/product/LV...and-sides?optionId=55981887&li=more-from-shop

 

[Bonsai Hunter]

@Bonsai Hunter,
Are you able to grow Tamarinds ? or Gmelina or Serissas ?
Would like to see your results with those. Enjoying your curiosity.
.

Hi Anthony, thanks. Tamarind is a slow growing species for an impatient person like me My fav is ficus religiosa, ficus racemosa & white lead tree. Please do visit my blog and youtube channel to see my crazy experiments. Though I started with blogging, I am increasingly migrating to Youtube as it has better viewership & engagement. I drop in here occasionally as its a good forum to learn/discuss/debate/fight etc

http://instantbonsaiforeveryone.blogspot.in/
https://www.youtube.com/user/VinnyChirayil/videos

 

[markyscott]

...In that case, please tell me why do bonsai pots have HUGE drainage holes ? They should all have just 1 hole as wide as your finger, covered with a mesh screen, isn't it. Why have 2, 4, 6 or 8 holes ? And why use a extremely fast draining and expensive Akadama soil imported all the way from Japan ? Why not use the locally available bonsai soil mix ? See the contradiction ?...

I'm not sure if it's a language issue or what, but we seem to have a hard time communicating. I'll try one more time. After that, you're on your own.

1. The key physical properties of the soil which affect plant growth are the air-filled porosity and the water-holding capacity, not the rate at which water falls out of the bottom of the pot. I supplied numerous references in my resource you can read if you choose to not take my word for it.
2. Bonsai growers use the term "fast draining" because we can see it. Whereas we can't see AFP and WHC. "Fast-draining" soils tend to have a high AFP, which is good. But "fast-draining" alone is not a useful measure of soil quality because, as you have shown, it is a function of lots of things like the number and arrangement of drainage holes. So you've made a good observation - the rate of gravitational drainage is a function of the pot. But you're conclusion, the number of holes in the bottom of the pot is the most important thing for "drainage", is just wrong. You're video clearly illustrates why drainage rate alone is not a very useful measure of soil quality.
3. Ones choice in soil type has nothing to do with "drainage speed". That's meaningless as you've clearly demonstrated. It should have everything to do with AFP and WHC along with the soil chemistry and the care the grower is willing to dedicate to his or her plants. That's the thing that you still need to figure out.
4. Why do pots have a big hole on the bottom? Well they need a hole, so that water comes out. And it needs to be big, because if it was a pinhole I'd have to stand by the pot for 20 minutes until it's done draining to make sure it's been thoroughly watered and that it doesn't clog and leave the tree sitting in water all day.

...What you seem to be ignoring is that good pot drainage = good aeration for roots...

This is what I love about the internet. Some yokel from halfway around the world with one year experience growing bonsai and a backyard washbasin can tell someone whose worked in the field for 30 years, has a PhD and several patents along with a dozen or so papers in peer-reviewed journals and couple of book chapters he doesn't know what the hell he's talking about. What can I say - the internet is full of bad information. Adding yours to it won't hurt anything.

...In my video of the 2 plastic bonsai pots, which one would you choose, if both costed the same ?..

Can I choose neither? I choose pots based on what I think my trees look best in and I don't like the looks of either of those plastic bonsai pots.

...I mentioned poor drainage, poor aeration & zero air pruning. Do you deny all 3 ?

I mentioned that poor AFP and poor WHC of have nothing to do with number and arrangement of holes in the bottom of the pot. You can go on believing that they do - you can also believe that the world is flat and gravity happens because our skin is magnetic. Or you can test it yourself as I suggested in my last post. It makes no difference to me.

Air pruning is another conversation. Best to get this issue figured out before we move on to that topic.

Scott

 

[PiñonJ]

All the drainage holes need to do is let water out without it pooling, and let air in. The balance and distribution of water and air in the soil is determined by the soil composition, as @markyscott has said. What people commonly call the drainage layer on the bottom of the pot is actually the aeration layer.

 

[Anthony]

@Bonsai Hunter,

okay I understand you are at an average of 542 m [ 1,778 feet ] weather is presently 20 deg.C

Tamarinds on our side can pack on 2.5 cm to 8 cm [ 1 to 3 inches ] in a year or two on our side,
but we won't reach 20 deg.c until next month and that is only 3 to 4 times a week rest of the
time will be 22 deg.C and these are night temperatures. Days will be around 30 deg.c for a high
of half an hour or less.

BUT we also ground grow and you are in an apartment.

Your cold would slow the Tamarind. Interesting to see you use ficus.

Will take some time and look at the you tube and blog.
Thank you.
Good Day
Anthony

 

[Anthony]

Mark

I think Vinny has only been doing Bonsai in an apartment for one year.
Newbie. Lots of patience as he finds his way ??

Remember 3 to 5 years [ if doing daily ] to master Horticulture / watering / soil / Health.

Experimenting to understand.
Good Day
Anthony

 

[markyscott]

Mark

I think Vinny has only been doing Bonsai in an apartment for one year.
Newbie. Lots of patience as he finds his way ??

Remember 3 to 5 years [ if doing daily ] to master Horticulture / watering / soil / Health.

Experimenting to understand.
Good Day
Anthony

Thank you for the reminder, Anthony. I'm usually a patient person, but frustration got the better of me today. My name is Scott, by the way.

Scott

 

[namnhi]

Mark

I think Vinny has only been doing Bonsai in an apartment for one year.
Newbie. Lots of patience as he finds his way ??

Remember 3 to 5 years [ if doing daily ] to master Horticulture / watering / soil / Health.

Experimenting to understand.
Good Day
Anthony

You got me confused about Scott's name.

 

[Solange]

I havent made any point so far. I am SEEKING info/opinion on a design aspect. On my youtube video too i have merely raised a question, seeking info/opinion. I do see shortcomings on the bonsai pot design and soon intend to give my take on it - in black and white, no grey areas, in my next video. I have already admitted I havent worked with ceramic pots but who in this forum has worked with a ceramic bonsai pot with multiple holes of the the type i illustrated ? Is there even one person ?

Who has? I have. They are weaker. Frost proof is a buzz phrase by the way. It does not mean freeze proof, which no ceramic on earth is. If ice can explode steel pipes it will explode your bonsai pot, unless you are using well drained soil.