Nursery Pots, Anderson Flats, Grow Bags, or Collanders

[JBP_85]

Hi Everyone,
I've been looking around at options for repotting my seedlings/tiny trees (Tridents, Dawn Redwood, & Bald Cypress) in the spring. I have a plan for RoR for one or two of my Tridents and more traditional informal upright styling for my other trees. It has been suggested that I get them into larger pots (possibly cut down 10 - 15 gal nursery pots) in order to establish a good radial root systems. My question is what route should I go here? It seems like the Anderson Flats are popular here but I also read about people using collanders and grow bags as well. Is there a flow chart somewhere I can use to help make this decision lol? Are there advantages to one over the other? I'd be interested to hear your experiences/preferences. I'm sure I'll have questions about what substrate works well for each option immediately after this so fell free to chime in there as well. Thanks as always!

 

[Wires_Guy_wires]

I'm not a big fan of bags. I have some cheap fabric bags for seedlings, they're OK but I have them in a collander because the soil shifts a lot when you move them. They need some kind of frame to keep them steady (and off the floor so that air can actually do some work).
Yes, they work, but they aren't great.

Collanders are better. Anderson flats would work just as well but they're more expensive to make.

Also, air pruning might be something to avoid for roots over rocks, you want those fat pipe roots and not a dense mat of fine feeders. So maybe a regular container would work better. Although.. Both root types can have their advantages and drawbacks.
I'm reporting no ill effects of using regular nursery pots with a coarse soil around the rock and a finer soil around the bottom of the rock.

 

[BrianBay9]

I'm not a big fan of bags. I have some cheap fabric bags for seedlings, they're OK but I have them in a collander because the soil shifts a lot when you move them. They need some kind of frame to keep them steady (and off the floor so that air can actually do some work).
Yes, they work, but they aren't great.

Agree about the bags. Tried them and moved on.

 

[Paradox]

I also dont like the grow bags.
Prefer a more rigid container.

Id use a colander for smaller trees and the anderson flats for larger things that are too big for a colander

 

[sorce]

flow chart

Yes!

For me, everything depends on the stage of development of the roots. Of course what type of roots matter, long for ROR, or fine for things ready for fine, but the system of getting there remains the same.

It's important to remember it's a circular system.
Root growth isn't only determined by soil and pot.

Soil and Pot determine root growth, which determines top growth, which determines root growth into Soil and Pot.

I believe they are programmed to grow exactly the same on top as below, though this is impossible.

That is One Section of Consideration. The whole system including YOU!

Second Consideration, is the aesthetic Section.

How many divisions of the nebari would you like to see?
The answer to this question will determine how long something has to be in a particular pot/soil situation. How long depends on Health and the other Sections.

Third Consideration is Soil/Pot Section.

I've found that Everything Ever Said of Soils is True. Seriously. That is Important.

I feel like I can speak directly on what I'm familiar with. Though cruising around here with the purpose of gathering this information is quite expanding.

Basically, the further you lean to mud and in-ground, the more initial stage divisions you produce. The more you lean to loose soil and airy pots, the more you freeze your initial divisions at their size and produce feeder roots.

In Considering these 3 Sections, we can understand how to best move forward with what should ALWAYS be our first goal, Nebari.

It is only with a continuously feeding matt of roots that we can properly continue to develop our tops.
This whole, remove everything in spring and expect to also develop a good top doesn't work.
Completely removing everything should only be done while developing initial divisions, while doing everything possible to keep feeder roots.

Can't have a sacrifice branch without a sacrifice root.

Of Containers.

I put everything in the same soil/basket, though not the best situation, it allows a solid understanding of the water needs of individual types of trees. This allowed me to recognize how much water these Junipers actually need in fall, where placed in nursery soil that is "more retentive", I allowed them to dry out and suffer/die.

This shows the difference in a soils capability to transfer water around the pot to get to the roots. DE has no problem wicking more water towards a core using it up. Where Nursery soil, though wet an inch down, is dry AF where it matters, because it lacks this ability to transfer water around the pot to where it is needed.

That's why I can't stand the whole...."stick your finger an inch in" BS. It LIES!
Not to mention the existence of pots a half inch deep.

Just frigging water more. MORE!

More of Containers....

Wet to Dry. Thick Black Rubber containers, to Window Screen Only. That scale matters.

Another thing that kinda bothers me is the loose usage of the term colander.
Of a hundred colanders, one is a Proper Air Root Pruning Device. Once lined with screen, this double wall diminishes 80% of air pruning capability.
This is important because you can't "freeze", or more accurately, you can't fine tune the freezing of you initial divisions of you have roots circling a BS colander.

Resorce.

Sorce

 

[sorce]

Cut Back to your Division.

Don't cut back and hope for Division.

Sorce

 

[JBP_85]

Yes!

For me, everything depends on the stage of development of the roots. Of course what type of roots matter, long for ROR, or fine for things ready for fine, but the system of getting there remains the same.

It's important to remember it's a circular system.
Root growth isn't only determined by soil and pot.

Soil and Pot determine root growth, which determines top growth, which determines root growth into Soil and Pot.

I believe they are programmed to grow exactly the same on top as below, though this is impossible.

That is One Section of Consideration. The whole system including YOU!

Second Consideration, is the aesthetic Section.

How many divisions of the nebari would you like to see?
The answer to this question will determine how long something has to be in a particular pot/soil situation. How long depends on Health and the other Sections.

Third Consideration is Soil/Pot Section.

I've found that Everything Ever Said of Soils is True. Seriously. That is Important.

I feel like I can speak directly on what I'm familiar with. Though cruising around here with the purpose of gathering this information is quite expanding.

Basically, the further you lean to mud and in-ground, the more initial stage divisions you produce. The more you lean to loose soil and airy pots, the more you freeze your initial divisions at their size and produce feeder roots.

In Considering these 3 Sections, we can understand how to best move forward with what should ALWAYS be our first goal, Nebari.

It is only with a continuously feeding matt of roots that we can properly continue to develop our tops.
This whole, remove everything in spring and expect to also develop a good top doesn't work.
Completely removing everything should only be done while developing initial divisions, while doing everything possible to keep feeder roots.

Can't have a sacrifice branch without a sacrifice root.

Of Containers.

I put everything in the same soil/basket, though not the best situation, it allows a solid understanding of the water needs of individual types of trees. This allowed me to recognize how much water these Junipers actually need in fall, where placed in nursery soil that is "more retentive", I allowed them to dry out and suffer/die.

This shows the difference in a soils capability to transfer water around the pot to get to the roots. DE has no problem wicking more water towards a core using it up. Where Nursery soil, though wet an inch down, is dry AF where it matters, because it lacks this ability to transfer water around the pot to where it is needed.

That's why I can't stand the whole...."stick your finger an inch in" BS. It LIES!
Not to mention the existence of pots a half inch deep.

Just frigging water more. MORE!

More of Containers....

Wet to Dry. Thick Black Rubber containers, to Window Screen Only. That scale matters.

Another thing that kinda bothers me is the loose usage of the term colander.
Of a hundred colanders, one is a Proper Air Root Pruning Device. Once lined with screen, this double wall diminishes 80% of air pruning capability.
This is important because you can't "freeze", or more accurately, you can't fine tune the freezing of you initial divisions of you have roots circling a BS colander.

Resorce.

Sorce

Wow! Thanks for the detailed reply! There is a lot here for my ADD brain to unpack and process lol. I’ll be in touch with stupid questions soon I’m sure lol.

 

[Prozart]

Another thing that kinda bothers me is the loose usage of the term colander.
Of a hundred colanders, one is a Proper Air Root Pruning Device. Once lined with screen, this double wall diminishes 80% of air pruning capability.
This is important because you can't "freeze", or more accurately, you can't fine tune the freezing of you initial divisions of you have roots circling a BS colander.

Resorce.

Sorce

Hey Sorce, quick question regarding your post. I've got a few trees that are currently in various forms of nursery pots that I plan to put in colanders this spring. Right now I have a few from the dollar store that seem to have big enough holes (some toward the top are actually a little too big but I think it'll be alright). I'm looking to buy a few more and I was just curious which colanders you use or if you just have an amalgamation of different ones that have the right sized holes.

Thanks!

 

[sorce]

@Prozart when it comes right down to it, nothing beats these.

Those Pot Materials!

Tired of going downstairs to pick up trees that test gravity in the wind, and understanding the benefits of colanders, I decided to solve a couple problems. Crappy pots, and crappy broken pots! One 4in clay completely destroyed, in a sock holding it together. Ham containers, small nursery...

www.bonsainut.com

Here is my Walmart Ficus after a couple seasons growing out into the ground.



I'll be able to tie that flap back and keep using this for a hundred more years.

The non-UV protected zip tie I used to hold it together, like a "colander", fell apart years ago, the basket remains rigid enough for use.

I have been thinking recently of building up pillars on the corners, probably around a thin rebar, to be able to extend the size capability. Doing everything possible to keep the slab as thin as functionally possible to reduce weight. Holes are a possibility...

But I can't get over how well these drainless flat bottoms produce. A "tile" without the hassle.

Sorce

 

[Firstflush]

I have tried the 15-30 gal nursery pot cut down. I find it way too flexible which would disturb the roots too much.
You would have to frame it for it to work or place it on a bench and leave it undisturbed.

 

[Prozart]

@Prozart when it comes right down to it, nothing beats these.

Those Pot Materials!

Tired of going downstairs to pick up trees that test gravity in the wind, and understanding the benefits of colanders, I decided to solve a couple problems. Crappy pots, and crappy broken pots! One 4in clay completely destroyed, in a sock holding it together. Ham containers, small nursery...

www.bonsainut.com

Here is my Walmart Ficus after a couple seasons growing out into the ground.

Ohhh yeah, you're the guy with those pots! I've read your thread, I forgot that was you. I actually looked into making them, and may still, but for now since I've only got a few plants I'll probably just stick with my cheap colanders until they inevitably fall apart on me, lol.

 

[casun]

All of my trees are in either nursery pots or colanders (approx. 50/50). The nursery pots seems to retain more moisture which, for me, is a negative so I prefer colanders. Once my trees get large enough I plan to try Anderson flats.

 

[Shibui]

All the products mentioned have uses for bonsai. Some people prefer one, others another and they will all tell you the one they use is the best. Truth is more like all have similar success rates if used correctly.
Trees here do not do as well in very shallow containers. I get better results in deeper pots with regular decisive root pruning to direct the roots and encourage lots of root division as I believe @sorce alluded to earlier.
Deeper containers are definitely better to start roots for ROR but don't let the trees and roots get too thick or they may not bend well and conform to the shape of the rocks.

Don't get too hung up an which is better. You can grow great bonsai in most containers. When starting out I would try a few different options as one or the other may be better for your ways and your local conditions than for others growing in far places.

 

[Bonsai Nut]

I use Anderson flats because they are larger than many alternatives (15" square), are the proper dimensions (wide and shallow), and are extremely thick plastic so that I can reuse them more or less indefinitely.

Otherwise they are just a container with tons of drainage. Any other container with similar dimensions and tons of drainage would work equally well.

 

[jeef16]

I use Anderson flats because they are larger than many alternatives (15" square), are the proper dimensions (wide and shallow), and are extremely thick plastic so that I can reuse them more or less indefinitely.

Otherwise they are just a container with tons of drainage. Any other container with similar dimensions and tons of drainage would work equally well.

how do you feel about anderson flats for enlarging or rapid development? I have a bunch of trident maple seedlings that I want to grow in a raised bed, but another consideration is growing them in anderson flats that are semi-buried so the roots can escape from the bottom? or am I just overthinking this and should just go straight to planted on a tile in the garden bed?

 

[Brian Van Fleet]

how do you feel about anderson flats for enlarging or rapid development? I have a bunch of trident maple seedlings that I want to grow in a raised bed, but another consideration is growing them in anderson flats that are semi-buried so the roots can escape from the bottom? or am I just overthinking this and should just go straight to planted on a tile in the garden bed?

If you want to fatten a trunk, nothing is faster than planting in the ground and letting it run. Just be sure to get the roots right first.

 

[penumbra]

I'm not a big fan of bags. I have some cheap fabric bags for seedlings, they're OK but I have them in a collander because the soil shifts a lot when you move them.

I use a lot of bags. I pack them tightly into a flat and don't move bags individually. I also have many bags in growing beds.

 

[Bonsai Nut]

how do you feel about anderson flats for enlarging or rapid development? I have a bunch of trident maple seedlings that I want to grow in a raised bed, but another consideration is growing them in anderson flats that are semi-buried so the roots can escape from the bottom? or am I just overthinking this and should just go straight to planted on a tile in the garden bed?

They are better than pond baskets, and definitely better than bonsai pots, but not nearly as good as ground growing in that respect.

However, a short-cut is to put your Anderson flat on the ground, and the tree roots will pass through the bottom of the pot and into the soil. Just make sure to lift the flat once a year and trim all the roots going out the bottom!

 

[penumbra]

However, a short-cut is to put your Anderson flat on the ground, and the tree roots will pass through the bottom of the pot and into the soil. Just make sure to lift the flat once a year and trim all the roots going out the bottom!

Last year I had all of my pond baskets and flats on pallets to help prevent soil pathogens. It is probably something I did not need to do. This year I am getting rid of som of the pallets and putting the baskets on a mixture of wood chips and mulch. I will not do all of them but certainly the well established ones. Hopefully it will cut down on watering requirements a bit.

 

[Bonsai Nut]

Last year I had all of my pond baskets and flats on pallets to help prevent soil pathogens. It is probably something I did not need to do. This year I am getting rid of som of the pallets and putting the baskets on a mixture of wood chips and mulch. I will not do all of them but certainly the well established ones. Hopefully it will cut down on watering requirements a bit.

It all depends on what I am doing. Most of the time I have my pond baskets and flats off the ground because it helps with drainage. But some of my bigger trees I have on the ground because I want the strength and growth of letting the roots run out the bottom. This includes three trees that have nasty low grafting scars and which I am using in the short term for cutting stock and which (when the trunks thicken enough) I will eventually air-layer.