Air Prune pots? Never again!

[Clicio]

Well, I have fallen for the siren's chant and purchased 2 air prune pots, one XXL and one XL, from AliXPress.
During the winter of 2021, one and a half years ago, I've reppoted a big Malus and a fairly big Dawn Redwood into the pots, to get more fine roots closer to the trunk.
It worked pretty well, and the trees have been doing great so far.
But not the pots.
The pots are made of a thin black plastic that is NOT anti-UV, so they deteriorate faster than I thought.
The consequence is, now I must repot both trees in the Summer - I am in the Southern hemisphere - because the pots are literally falling apart.
A waste of time, energy, substrate, and risky for temperate deciduous and conifers.
Some pictures of the Malus and the self destroying pot below.

Tree in training, recovering from a hard pruning in the previous winter.


Botton of the pot falling apart.


Detail 01


Detail 02


My conclusion is, they don't meet my standards for bonsai in training, where the same pot could be in use for a few years, or sometimes many years. They just put the health of the trees in risk and that is unacceptable.

 

[Shibui]

Agree that plastic planters should last much longer than a couple of years. Surprised to see those pots deteriorating so quick. I've used the same style but the plastic has lasted for many years. Must be a different manufacturer?

Transplant now should not be such a big deal. You should find lots of air pruned roots all round the perimeter which will hold the soil together. The type we use open right down one side so very easy to peel it off with minimal disturbance to the root ball. Just pop them into a new pots and backfill the space. Your tree should not even notice the change.

 

[It's Kev]

I tried it once, then had a bit of a too firm grip when I picked it up, and cracked everywhere my hand touched.

Aaaaand my stupid gif wouldn’t upload

 

[Clicio]

Surprised to see those pots deteriorating so quick. I've used the same style but the plastic has lasted for many years. Must be a different manufacturer?

Surely, I got mine from Ali XPress which means China. I was expecting a heavier, thicker walled plastic and UV resistant, but the product I received was very thin.
Yes, they open from the side, so it will be a slip potting I guess.
Thanks for sharing your experience, Shibui.

 

[Maiden69]

@Clicio the problem you have is that you bought from AliExpress instead of the original one. While they work well for a year, those ones are not made with quality ABS or polystyrene. This is where I buy mine , even the construction is different. I don't know how much will be the shipping to Brazil... so that is one thing to take in mind. Also, I had great success with the Rootpouch brand as in-ground grow bags for my above ground planters. Does the same thing, but instead of air-pruning, it prunes by entrapment. I know they have a few global distributors, so they may be available to you locally. Rootmaker also have bags, but they are for above ground only while Rootpouch gave both above and in-ground.

 

[Clicio]

@Clicio the problem you have is that you bought from AliExpress instead of the original one. While they work well for a year, those ones are not made with quality ABS or polystyrene. This is where I buy mine , even the construction is different.

Yes, you are right. It's not the same product at all.
Thanks for the link and for the tips, I will check the fares and taxes due so they can ship them to Brazil. I appreciate your suggestions!

 

[Clicio]

UPDATE:

1-) As @Shibui and @Maiden69 have said, it's a matter of me buying the cheap product, NOT the technology itself.
2-) The plants are full of fine feeding roots, none circling the pot (as expected), and I am very satisfied with the results.

During and after repotting, today:

Roots, lots of roots!


After slipping it into the new conventional plastic pot.

After guy-wiring it again.

 

[Clicio]

Today I have finished the same procedure on a Dawn Redwood, that was also in a Chinese air pruner pot falling apart.
Back it went to a plastic training pot.
It's a big tree, almost as tall as myself.

 

[BrightsideB]

Today I have finished the same procedure on a Dawn Redwood, that was also in a Chinese air pruner pot falling apart.
Back it went to a plastic training pot.
It's a big tree, almost as tall as myself.

View attachment 466691

Very nice Dawn redwood. I would never be able to keep one alive in a small pot like that. every time I look at mine the soil is dry.

 

[Eckhoffw]

Very nice Dawn redwood. I would never be able to keep one alive in a small pot like that. every time I look at mine the soil is dry.

Today I have finished the same procedure on a Dawn Redwood, that was also in a Chinese air pruner pot falling apart.
Back it went to a plastic training pot.
It's a big tree, almost as tall as myself.

View attachment 466691

Beautiful trees @Clicio! Thank you for sharing.

So what I’m getting, is that these Air prune pots are effective - You had great root development. However, one should buy the original heavy duty version.
may have to try some.

Would you say you prefer this style of container over a pond basket?
Species dependent.

 

[Clicio]

Beautiful trees @Clicio! Thank you for sharing.

Thanks, I try my best, and our climate helps...

So what I’m getting, is that these Air prune pots are effective - You had great root development. However, one should buy the original heavy duty version.
may have to try some.

Exactly, the roots are fine, healthy, close to the trunk and plenty.

Would you say you prefer this style of container over a pond basket?
Species dependent.

It seems weird, but we can't get pond baskets here in Brazil. Colanders yes, but not the baskets, so our options are limited, that's why we had to try those.
But they work alright.
Thanks for commenting.

 

[Clicio]

Very nice Dawn redwood. I would never be able to keep one alive in a small pot like that. every time I look at mine the soil is dry.

We water it three times a day during the summer months.
And...
It rains every single day.

 

[cmeg1]

Wow…love the redwood @Clicio

Hands down I still say Rootpouch Brand fabric pots are the best…… they prune by entrapment pruning not air pruning which means the root gets tangled in the fabric and while you may still get circling roots,a very few ,and some may still poke out a little bit ….they sell different weave options that you can actually sink the pot into the ground over winter while they still are pruning themselves by entrapment in the fibers inside the pot ……and then uplift the pot after winter storage ……the regular AirPods do not do this! even the fabric air pruning pots, as the roots grow through and defeat the purpose of become a ground tree which is not good cause’ you will have to do a regular tree lift from the ground then anyway……
Rootpouch are great……they have 5-7 year? Weaves of fabric type.
I used little 1 pint…. 1-2 year weaves for this pine.

I actually kind of miss using them a little bit……..it’s just the stonewool so much more economical in time and expense.

 

[R0b]

Well, I have fallen for the siren's chant and purchased 2 air prune pots, one XXL and one XL, from AliXPress.
During the winter of 2021, one and a half years ago, I've reppoted a big Malus and a fairly big Dawn Redwood into the pots, to get more fine roots closer to the trunk.
It worked pretty well, and the trees have been doing great so far.
But not the pots.
The pots are made of a thin black plastic that is NOT anti-UV, so they deteriorate faster than I thought.
The consequence is, now I must repot both trees in the Summer - I am in the Southern hemisphere - because the pots are literally falling apart.
A waste of time, energy, substrate, and risky for temperate deciduous and conifers.
Some pictures of the Malus and the self destroying pot below.

Tree in training, recovering from a hard pruning in the previous winter.
View attachment 466552

Botton of the pot falling apart.
View attachment 466553

Detail 01
View attachment 466555

Detail 02
View attachment 466554

My conclusion is, they don't meet my standards for bonsai in training, where the same pot could be in use for a few years, or sometimes many years. They just put the health of the trees in risk and that is unacceptable.

I was under the impression these are ment to be dug into the ground.

 

[Bonsai Nut]

I was under the impression these are ment to be dug into the ground.

It would defeat the purpose if they were dug into the ground. The idea behind an "air-pruning" pot is that the tree roots grow and expand to occupy all the moist soil space - but the moment they reach the exterior of the root-ball (the pot) they dry out and cannot extend further. They are literally pruned by contact with air. If you were to put that pot in the ground, roots would run through all the holes, and in a year or two they would bust the pot apart.

 

[It's Kev]

@Clicio i saw your air prune pots in a shop today(sorry, no pics taken). One buy’s them by length in flat sheets and stick it together with zip ties. In that case, I’m better off with the plastic colanders that the grannies strain their peas in here.

 

[Clicio]

Wow…love the redwood @Clicio

Thanks @cmeg1 , it's a big baby.

Hands down I still say Rootpouch Brand fabric pots are the best…… they prune by entrapment pruning not air pruning ...
Rootpouch are great……they have 5-7 year? Weaves of fabric type.

Aha, sounds like a very good idea!
I'll try to get some here and try them.
Thanks for your useful tips!

 

[Clicio]

@Clicio i saw your air prune pots in a shop today(sorry, no pics taken). One buy’s them by length in flat sheets and stick it together with zip ties. In that case, I’m better off with the plastic colanders that the grannies strain their peas in here.

Yes, flat sheets and you get to choose the bottoms, that's how I have got them from China. Convenient but the plastic is very weak.