Ground Growing vs. Colanders

[Ohmy222]

One of the biggest difficulties with ground growing is that people may not have the ground

For some folks, it is hard enough to have enough room to grow trees outside, let alone stick them in a plot of soil.

agreed, also if you have it, what is the area like. If you want to grow pines or junipers then you need some good sun. Doesn't work if your land is in shade. Even maples want sun.

 

[DrTolhur]

In my experience air pruning does not always produce magnificent root development for bonsai. The vast majority of root division occurs near the growing ends so in a colander root division happens near the outer ends of the roots, at the colander mesh, rather than close to the trunk where we, as bonsai growers, want it. Lrger colanders just move the ramification further from the trunk.

Isn't that why you'd need to match colander size to tree size? I've heard something about a 4" rule, where an air-pruned root tip will send out new growth up to 4" behind the tip. So you'd want a plant the tree in a colander no more than 4" in diameter larger than where you want root proliferation. Then, as you get a good root mass and the tree grows, you go to a larger colander to expand the ramification out.

 

[Shibui]

Isn't that why you'd need to match colander size to tree size? I've heard something about a 4" rule, where an air-pruned root tip will send out new growth up to 4" behind the tip. So you'd want a plant the tree in a colander no more than 4" in diameter larger than where you want root proliferation. Then, as you get a good root mass and the tree grows, you go to a larger colander to expand the ramification out.

Not sure where the 4" rule comes from? My experience is that most new roots come from up to 1/4" behind the pruned tip so to get a well ramified root system the colander really needs to be the same size as where you want the roots to start dividing and that would hardly seem conducive to good trunk growth IMHO.
I can achieve a similar result by root pruning at the appropriate spot and then plant into the ground where both roots and trunk will grow more rapidly than any colander.

Just my observations over 30 years of field growing trees for bonsai but obviously applicable to this region. Mileage may vary in other locations.

 

[Shibui]

Just out of curiosity - how come?

If the tree looks good initially, and then it is grown correctly then why would it not produce great bonsai material. It is a total contradiction here.

Can you explain your train of thought here?

My guess it is a matter of perspective. Trees and branches that look good on a landscape sized tree don't always look so great when reduced to bonsai size.

A great many trees look really good in the wild. This applies to trees to be collected and to branches for layering. They look great when you first see them. After the dig or layer gets the tree separated you start to see how little taper there is or how few branches there really are. After it goes into a training pot they look even worse.
Many times I've wondered why I ever chose that tree/branch. After a year or 2 of development I've thrown out or sold at least 3/4 of layers or collected trees.

Eventually I've learned to be much more selective in choosing suitable starting material so keeper rates are now better but it still surprises me that so many trees that originally looked great become mediocre or worse when they are potted up.

Layers are no different. Branches that appear to have good movement and taper don't always look the same when you get roots started and into a pot. Branches on landscape trees tend to have long internodes so sub branches are often further apart than desirable for bonsai but that's not always obvious until the scale changes from landscape size to potted bonsai size. Getting new shoots to sprout can be difficult on many species if there's no nodes where the new shoots are needed.
I've also tended to underestimate the size of chops required to reduce a branch to bonsai size so many years required for those to heal or convert to dead wood.

Layers taken from existing bonsai are completely different case. Scale, size, internodes and ramification are generally already established and some great, almost instant, trees have been layered off existing bonsai.

Looking at other people's choices for dig material and for layers with the hindsight of 40 years I see so much material that I think will just be frustrating to develop further. By all means have fun. Most people will learn lots from the experiences but don't expect quick or outstanding results from landscape layers.

 

[jerzyjerzy]

OK, thanks

So, you basically mean that the layered part can look good on the tree in the wild, but not necessarily good when cut off and potted.

I actually agree with this statement 100%. When I look at some of my layers collected this year, I also think "What did I see when I planned this, really?" Some others came out great, though, so it is just some time lost on unnecessary work.

It is just my hobby, not a living, and I can afford it but, of course, I could use my time much better. I promised myself to pay better attention this year.

 

[papkey5]

The quintessential technique for faster growth seems to be planting in the ground. But the quintessential technique for great root development seems to be air pruning roots with pond baskets, colanders, Anderson flats, etc. I'm wondering if anyone can compare and contrast the effects of these two practices. It seems like great root development would necessarily lead to a healthy and more rapidly growing tree since there's obviously a balance between roots and foliage, but I don't often see these two techniques talked about together.

Points of consideration for me:
1) Are these two techniques at all related as far as developing young trees, or are they used for completely separate purposes?
2) Is there a reason the root development of air pruning roots wouldn't produce the same level of trunk growth as ground growing?
3) Does it make sense to use both techniques (whether sequentially or together)? Related thread: https://www.bonsainut.com/threads/summer-only-ground-growing-jm.52200/

For context, my personal main concern is with respect to Japanese maples, but the conversation obviously need not be strictly limited to those.

For question # 2 anecdotal evidence. For two years now I have had a juniper (unknown variety) in a pond basket. Coming into its third year in said basket there has been no thickening trunk.

 

[The Warm Canuck]

The above is important regardless of the container or inground. Without regular repotting and root work in the early stages of development, the results are not the same.
I have found that there is some benefit to use colanders in the early stages. I have not found that air pruning only promotes bifurcation at the edge of the colander or pond basket. Quite the opposite in fact.
I have found that it is beneficial to change up to larger containers for the grow out process and prefer Anderson Flats for Japanese maples and tridents.
Once again, regular root work is desired for best results. No less than once every two years is my guideline for fast growing maples. If the flats are placed on the ground then it is wise to trim downward roots going into the ground on a regular basis as well or the drainage is adversely affected.

They will grow faster inground, but I find them more difficult to manage development properly and maintain root work with in the ground growing. much prefer to be able to put the tree on the bench for developmental pruning and root work.

I use the following sequence.
1.seed in tray ( Anderson flat)
2.seedlings in colander when transferred from seed tray. Colander on bench with water system. ( initial wiring to shape trunk movement lower down while still thin and pliable.)
3.year two or three put the colander in a grow bed. ( this allows me to lift for too work, turn and replace at the beginning of each growing season. Continue Wire for movement id desired)
4.Year five place in Anderson flat for continued grow out/ cut back. ( at this point I have established a good starting nebari and some movement in the bottom portion of the trunk by wiring.

Note: two major factors prevent me from growing out in the field.
1. rocky soil in my terrain. Glacial till on the mountain slopes. ( I use raised grow beds to counteract the rocky terrain)
2. Advanced age, laying on my stomach to work on trees is not my idea of fun, doing it from as bent position is even less fun. The raised beds help with this aspect for early stages of development. Would require too much infrastructure to grow out larger numbers in constructed beds.

Frank, are your beds all filled with Bonsai soil?

 

[River's Edge]

Frank, are your beds all filled with Bonsai soil?

Initially the beds were a combination of Pumice, lava and sea soil. Over the years I have eliminated the sea soil and use pumice, lava and granite grit. As I recycle used soil from bonsai pots and grow boxes to add to the beds over time some Akadama has been worked in. if I had to guess at this point the makeup would likely be 60% pumice, 15% lava, 15% granite, remainder Sea Soil, Akadama, Kanuma.
The bottom layer of each grow bed is rough larger black lava ( 1") on top of landscape fabric. the next layer is larger pumice ( 1/2") , then medium particles of the entire mix. Wanted better drainage and some barrier for roots from the surrounding forest. Has worked pretty well.

 

[jeremy_norbury]

I put pond baskets in trays of bonsai substrate like this:

IMG_4054 by Jerry Norbury, on Flickr

Additionally I built some holding boxes - also filled with substrate:

IMG_3880 by Jerry Norbury, on Flickr

 

[Lorax7]

I put pond baskets in trays of bonsai substrate like this:

Why?

 

[River's Edge]

Why?

Why not?
If I may, there are several major advantages with this approach.
The containers allow for root growth, ease of work on the developing tree, simple root pruning and rotation of the plant. Pond baskets in the ground allow for lateral root growth and do not specifically encourage circling roots or downward roots like some containers. They also have superior drainage and do not pool water in the bottom like other containers. So not the same issues in wet climates if the substrate chosen is suitable.
Having the containers in a grow bed allows for more efficient watering and more stable growing environment for the roots.
Win/Win combines the benefits of container growing with in ground development.
Very effective for certain stages of developing Bonsai.
Also very effective for wintering over many species for the same stability of environment reasons. The ground temperature gives a longer growing season and less freezing effect than being above ground outside.
Not sure how Jeremy would describe it but it could also include the fact that local soil or location is not suitable for in ground growing. That is the case in my location. So the grow beds are an excellent substitute.

 

[Lorax7]

Why not?
If I may, there are several major advantages with this approach.
The containers allow for root growth, ease of work on the developing tree, simple root pruning and rotation of the plant. Pond baskets in the ground allow for lateral root growth and do not specifically encourage circling roots or downward roots like some containers. They also have superior drainage and do not pool water in the bottom like other containers. So not the same issues in wet climates if the substrate chosen is suitable.
Having the containers in a grow bed allows for more efficient watering and more stable growing environment for the roots.
Win/Win combines the benefits of container growing with in ground development.
Very effective for certain stages of developing Bonsai.
Also very effective for wintering over many species for the same stability of environment reasons. The ground temperature gives a longer growing season and less freezing effect than being above ground outside.
Not sure how Jeremy would describe it but it could also include the fact that local soil or location is not suitable for in ground growing. That is the case in my location. So the grow beds are an excellent substitute.

I should've been more specific. I'm not questioning the value of putting pond baskets on top of a growing medium to let the roots escape out the bottom and accelerate growth by allowing the tree to gather additional resources with its expanded root network. I'm asking, why use expensive bonsai substrate in these trays? It seems unnecessary. Plain ol' dirt or mulch would work just fine for the media outside of the pond basket.

 

[jeremy_norbury]

I should've been more specific. I'm not questioning the value of putting pond baskets on top of a growing medium to let the roots escape out the bottom and accelerate growth by allowing the tree to gather additional resources with its expanded root network. I'm asking, why use expensive bonsai substrate in these trays? It seems unnecessary. Plain ol' dirt or mulch would work just fine for the media outside of the pond basket.

Substrate doesn't need to be expensive - this is a combination of diatomaceous earth cat litter and LECA clay - this works out at €0.30/litre or $1.30/gal in freedom units.

I needed about 150 litres so it cost me about €45/$52.

 

[Lorax7]

Substrate doesn't need to be expensive - this is a combination of diatomaceous earth cat litter and LECA clay - this works out at €0.30/litre or $1.30/gal in freedom units.

I needed about 150 litres so it cost me about €45/$52.

That makes a lot more sense now. At first glance, just looking at the photos on my phone, I thought it was some variation of a Boon mix (akadama, pumice, lava). That was the origin of my perception that it would be really expensive to do this.

 

[River's Edge]

I should've been more specific. I'm not questioning the value of putting pond baskets on top of a growing medium to let the roots escape out the bottom and accelerate growth by allowing the tree to gather additional resources with its expanded root network. I'm asking, why use expensive bonsai substrate in these trays? It seems unnecessary. Plain ol' dirt or mulch would work just fine for the media outside of the pond basket.

Not really, from my point of view it would destroy the optimum drainage of the bonsai soil by acting like a barrier and slowing drainage creating a more anaerobic condition below the pond baskets. This in turn would create a less aerobic condition for escaping roots and thus slow the growth. By using the same substrate the drainage remains the same and the moisture levels and oxygen levels are similar within the pond baskets and below.
Thus the benefit of expanding root systems is retained with the escaping roots and there is no interference with drainage within the basket. The key being retaining similar particle size and function of the substrate.
In my case the pumice and granite grit combined with lava is relatively inexpensive without Akadama or Kanuma.

Keep in mind that substrates vary by cost immensely depending on location. Pumice, granite grit and lava are all mined locally in my area, so they are easily obtained and relatively cheap. That may not be the case in Europe or the other side of North America.

 

[bonhe]

For me, I consider the bark is 2nd important for the species with special barks. With these species, I don’t want to grow them in the ground, to avoid discrepancy between bark size and tree height when they are placed into the bonsai pot later on ! Otherwise, ground growth is good to get the tree grow fast.
Thụ Thoại

 

[BigAbs321]

For me, I consider the bark is 2nd important for the species with special barks. With these species, I don’t want to grow them in the ground, to avoid discrepancy between bark size and tree height when they are placed into the bonsai pot later on ! Otherwise, ground growth is good to get the tree grow fast.
Thụ Thoại

Can you give some examples of species that you’d avoid planting in the ground?

 

[Crazy Diamond]

Substrate doesn't need to be expensive - this is a combination of diatomaceous earth cat litter and LECA clay - this works out at €0.30/litre or $1.30/gal in freedom units.

I needed about 150 litres so it cost me about €45/$52.

You guys have cool bonsai nurserys in the Netherlands?

 

[Lorax7]

Not really, from my point of view it would destroy the optimum drainage of the bonsai soil by acting like a barrier and slowing drainage creating a more anaerobic condition below the pond baskets. This in turn would create a less aerobic condition for escaping roots and thus slow the growth. By using the same substrate the drainage remains the same and the moisture levels and oxygen levels are similar within the pond baskets and below.
Thus the benefit of expanding root systems is retained with the escaping roots and there is no interference with drainage within the basket. The key being retaining similar particle size and function of the substrate.
In my case the pumice and granite grit combined with lava is relatively inexpensive without Akadama or Kanuma.

Keep in mind that substrates vary by cost immensely depending on location. Pumice, granite grit and lava are all mined locally in my area, so they are easily obtained and relatively cheap. That may not be the case in Europe or the other side of North America.

Keep in mind that drainage in the soil column outside of the constraints of a pot is drastically different from drainage of that same material in a pot. The soil column in the natural environment doesn’t have a bottom where a layer of water is perched, unless you live in a swampy area where the water table is close to the surface. That problem only exists because of growing in a container. You might have those issues in the trays if the tray isn’t very deep because, of course, the tray is still a container. However, you’re unlikely to have those issues for a pond basket sitting on the ground or sitting on a raised bed. You definitely won’t have drainage problems if the pond basket is sitting on a layer of mulch or wood chips as the material is more coarse than any of the soil components in the basket.

Regarding substrate cost, akadama is expensive everywhere except in Japan, because of freight costs. So, the idea that “Boon mix = inherently expensive” is valid everywhere except Japan (at least until someone decides to start up a mining operation somewhere else where the geology is similar.

 

[Clicio]

You can also use stainless steel colanders

I've been using *only* stainless steel colanders and the results are quite impressive.