Growing out large bonsai from starter material in pots

[FiggieSmalls]

Hey folks!

I hope I'm not in the wrong forum here. This post is really a question about growing big bonsai from starter material without a good backyard to grow it in. So it is about pots in that sense, but not about pots in the decorative sense.

I'm having some trouble finding a lot of information on this topic. It seems like growing trees in the field/ground is decidedly the best way to accelerate growth vs. growing in a pot. But sometimes, growing the tree in a pot is the only option.

So the question really is, how can we give trees a potted environment that most closely approximates the field in terms of fast growth?

It seems obvious that you would want to just use a really large pot. Preferrably something very wide and somewhat shallow. I'm thinking something 6-12 inches deep and 2-3ft long/wide. But I'm not seeing any products like this when I search online, making me wonder if I'm being crazy...

I've thought about just getting a big plastic tub, drilling holes in the bottom, and then filling it halfway with gravel, putting mesh lining above the gravel, and then place the tree and soil above the mesh.

Another possibility I've considered is to use a big 10+ gallon fabric pot. In theory this gets around the issue of circling roots. Does anyone have experience using large fabric pots to develop trees?

All suggestions are much appreciated, thank you!

Figgie

 

[NaoTK]

When you grow in the ground, the soil moisture level naturally equilibrates and the roots can grow where the moisture level is optimal. In a pot, the moisture level is often too high or too low. The problem with a big pot is if the tree is too small, the soil stays too wet for too long and this actually slows the rate of growth down "overpotting." You can slowly upgrade the size of the pot over time.

Grow bags do a good job of simulating the boundary conditions of growing in the ground by wicking water away.

 

[rockm]

I have grown all my bonsai over the last 30 years in a backyard that is 30 feet by 25 feet. I use primarily containers to grow out bonsai. Keep in mind that ground growing is used to develop the TRUNK and nebari of a tree. That can take considerable time in the ground and even longer, much longer, in a container.

My key to bonsai has been to start with material that is already "grown out." Starting with seeds or seedlings in such an environment is asking for a very very very very VERY long wait, without much success at the end. It is FAR easier and practical to begin with established trunks and grow out apex, branching, etc. than to try to grow a seed into a 3-8 inch trunk worth making into a bonsai.

I use this example a lot. But here is what is possible in pot in a small backyard. These are pictures of the oak stump I began with 28 years or so ago. It was dug up in Texas by a friend of mine. The trunk itself is about 250 years old. I put it in a container to work on developing an apex, all of its branching and refining its roots (which is a big advantage of container growing. Plant a stump like this back in the ground to do all the work I did on it would require RE-collecting it after 20 years--not an easy job and hard on the tree) The last pic is of what the tree has become. All that work was done in a container.

So, bottom line, you're thinking has to be re-adjusted. Growing from seed or using seedlings is a waste of time if you have no real way to grow them in the ground to develop their trunks (which is what the first 10-15 years of purpose-grown bonsai seedlings is all about). Use already grown-out trunks to begin.

 

[rockm]

growing in a pot to "fast grow" a tree is not simply putting it in a big to huge pot. In fact, doing that can slow it down or even kill it. Has to do with the soil volume in the pot vs root mass. Small root masses don't use up moisture as quickly as larger ones. That means a small root mass surrounded by a huge soil volume in a container tends to remain too wet. That wetness inhibits or kills off root development. All this cannot be compared to growing in the ground. In-ground is a different environment than in a container, as the ground has infinite drainage capabilities. A pot does not. That means water tends to stay in it for long periods without going anywhere. The "best" container to encourage growth is one that juuust fits the existing root mass, so those roots use water and resources up instead of being smothered by them. That means start with the smallest container, work your way up gradually to larger and larger pots over time as the roots grow. This is an extremely tedious process and it's all you will be doing for years with most seedling that you want to become larger trees...

 

[FiggieSmalls]

Hmmm, okay, this is all helping to sort of correct my thinking. I can understand why growing in the ground is fundamentally different vs in a pot and I was basically asking the wrong question to begin with, or maybe too specific.

I was also not clear about the premise of the question. I don't intend to throw a seedling into a giant pot or anything like that. I'm more just looking for wisdom on selecting the best pots to promote vigorous growth, I suppose. Since on one hand you have pots meant for developing a bonsai after it's reached its desired size, and on the other hand you have standard flower pots you'd find trees growing in at a nursery. I might be totally wrong, but neither of these seems ideal for maximizing growth. Well, traditional bonsai pots are definitely not ideal for max growth, but nursery pots I'm not sure. They could be taller and narrower than what is ideal, for example. But I would be starting with established trees that are 15-30 yrs old, I figure. I just want to let them grow bigger! But... in a pot still.

Let's consider my inspiration for a moment. I've been watching this YouTube channel--Heron's Bonsai. Hopefully you are all familiar with it . If not, definitely check it out! Anyway, the artisan in those videos, Peter Chan, talks about using flower pots to grow trees strong, as he would put it. But oftentimes I see him working with these special pots that are quite wide relative to how deep they are, and are "baskets" rather than an actual flowerpot. Basically they're made of a fine mesh instead of solid plastic. So he'll plant the tree in one of these baskets and then just set it on the gravel at the nursery and the roots go wild growing through the basket into the ground! And I'm talking deep into the ground... 2ft + a lot of the time. There's one clip I found particularly humorous of Peter all-out wrestling against a ~6ft tree that had grown into the ground this way while in a regular flowerpot, using the sheer weight of the tree (and his own bodyweight) struggling just to separate the pot from the ground to move the tree!!

So... maybe that's the real question I'm getting at is, would it be possible to replicate those conditions on say a deck atop a large tub of gravel (with drainage), in lieu of actual ground to use? In theory the gravel could provide a nice humid/damp environment for roots that wouldn't ever get overly soggy. P.S. I am willing to get sophisticated about creating this environment if necessary (and sufficient)

Then the followup question would be if anybody has used the sort of basket pots described, thoughts on their benefit (or not) and where to find them..?

Thanks!

 

[19Mateo83]

Hmmm, okay, this is all helping to sort of correct my thinking. I can understand why growing in the ground is fundamentally different vs in a pot and I was basically asking the wrong question to begin with, or maybe too specific.

I was also not clear about the premise of the question. I don't intend to throw a seedling into a giant pot or anything like that. I'm more just looking for wisdom on selecting the best pots to promote vigorous growth, I suppose. Since on one hand you have pots meant for developing a bonsai after it's reached its desired size, and on the other hand you have standard flower pots you'd find trees growing in at a nursery. I might be totally wrong, but neither of these seems ideal for maximizing growth. Well, traditional bonsai pots are definitely not ideal for max growth, but nursery pots I'm not sure. They could be taller and narrower than what is ideal, for example. But I would be starting with established trees that are 15-30 yrs old, I figure. I just want to let them grow bigger! But... in a pot still.

Let's consider my inspiration for a moment. I've been watching this YouTube channel--Heron's Bonsai. Hopefully you are all familiar with it . If not, definitely check it out! Anyway, the artisan in those videos, Peter Chan, talks about using flower pots to grow trees strong, as he would put it. But oftentimes I see him working with these special pots that are quite wide relative to how deep they are, and are "baskets" rather than an actual flowerpot. Basically they're made of a fine mesh instead of solid plastic. So he'll plant the tree in one of these baskets and then just set it on the gravel at the nursery and the roots go wild growing through the basket into the ground! And I'm talking deep into the ground... 2ft + a lot of the time. There's one clip I found particularly humorous of Peter all-out wrestling against a ~6ft tree that had grown into the ground this way while in a regular flowerpot, using the sheer weight of the tree (and his own bodyweight) struggling just to separate the pot from the ground to move the tree!!

So... maybe that's the real question I'm getting at is, would it be possible to replicate those conditions on say a deck atop a large tub of gravel (with drainage), in lieu of actual ground to use? In theory the gravel could provide a nice humid/damp environment for roots that wouldn't ever get overly soggy. P.S. I am willing to get sophisticated about creating this environment if necessary (and sufficient)

Then the followup question would be if anybody has used the sort of basket pots described, thoughts on their benefit (or not) and where to find them..?

Thanks!

It is common to see people placing their trees in smaller pots on top of a larger pots or putting their flats directly on the ground to let the roots escape and grow down and accomplish this same effect. I think it’s @Cajunrider that grows bald cypresses in pots on top of larger pots all sitting in a water tub. He’s simulating swamp conditions to help his BC grow vigorously. The baskets are Anderson flats. It’s very common, as is pond baskets. You can find similar flats on Amazon.

 

[crab apple]

Hmmm, okay, this is all helping to sort of correct my thinking. I can understand why growing in the ground is fundamentally different vs in a pot and I was basically asking the wrong question to begin with, or maybe too specific.

I was also not clear about the premise of the question. I don't intend to throw a seedling into a giant pot or anything like that. I'm more just looking for wisdom on selecting the best pots to promote vigorous growth, I suppose. Since on one hand you have pots meant for developing a bonsai after it's reached its desired size, and on the other hand you have standard flower pots you'd find trees growing in at a nursery. I might be totally wrong, but neither of these seems ideal for maximizing growth. Well, traditional bonsai pots are definitely not ideal for max growth, but nursery pots I'm not sure. They could be taller and narrower than what is ideal, for example. But I would be starting with established trees that are 15-30 yrs old, I figure. I just want to let them grow bigger! But... in a pot still.

Let's consider my inspiration for a moment. I've been watching this YouTube channel--Heron's Bonsai. Hopefully you are all familiar with it . If not, definitely check it out! Anyway, the artisan in those videos, Peter Chan, talks about using flower pots to grow trees strong, as he would put it. But oftentimes I see him working with these special pots that are quite wide relative to how deep they are, and are "baskets" rather than an actual flowerpot. Basically they're made of a fine mesh instead of solid plastic. So he'll plant the tree in one of these baskets and then just set it on the gravel at the nursery and the roots go wild growing through the basket into the ground! And I'm talking deep into the ground... 2ft + a lot of the time. There's one clip I found particularly humorous of Peter all-out wrestling against a ~6ft tree that had grown into the ground this way while in a regular flowerpot, using the sheer weight of the tree (and his own bodyweight) struggling just to separate the pot from the ground to move the tree!!

So... maybe that's the real question I'm getting at is, would it be possible to replicate those conditions on say a deck atop a large tub of gravel (with drainage), in lieu of actual ground to use? In theory the gravel could provide a nice humid/damp environment for roots that wouldn't ever get overly soggy. P.S. I am willing to get sophisticated about creating this environment if necessary (and sufficient)

Then the followup question would be if anybody has used the sort of basket pots described, thoughts on their benefit (or not) and where to find them..?

Thanks!

Lowes caries pond baskets, they're pretty affordable too and UV rated so they last awhile out in the sun.

 

[Cajunrider]

It is common to see people placing their trees in smaller pots on top of a larger pots or putting their flats directly on the ground to let the roots escape and grow down and accomplish this same effect. I think it’s @Cajunrider that grows bald cypresses in pots on top of larger pots all sitting in a water tub. He’s simulating swamp conditions to help his BC grow vigorously. The baskets are Anderson flats. It’s very common, as is pond baskets. You can find similar flats on Amazon.

Settling in with a method to grow BC pre-bonsai

After 3 years of trying just about every method that have been discussed here I have found the one that I am most comfortable with and see the fastest growing results for growing bald cypress. Once the tree is about 1/2 inch in diameter, I transfer it to an Anderson flat with mostly inorganic...

www.bonsainut.com

 

[FiggieSmalls]

Thanks!

It is common to see people placing their trees in smaller pots on top of a larger pots or putting their flats directly on the ground to let the roots escape and grow down and accomplish this same effect. I think it’s @Cajunrider that grows bald cypresses in pots on top of larger pots all sitting in a water tub. He’s simulating swamp conditions to help his BC grow vigorously. The baskets are Anderson flats. It’s very common, as is pond baskets. You can find similar flats on Amazon.

Thanks! Anderson flats, pond baskets, yes!!

Pot within a pot should be an interesting method to attempt. I guess the details of how to set it up just right will depend on the plant species and things I'll have to learn through experimentation. My initial thought is if I did a pot on top of a pot of just gravel, the gravel would dry up pretty quickly... so maybe to counteract that I would want to put a thin layer of sand or clay at the bottom (under the gravel) to slow the drainage a bit? Or maybe I should just install some little spray pumps in the gravel container to maintain a consistent moisture level in the gravel at all times... hehe

 

[FiggieSmalls]

Settling in with a method to grow BC pre-bonsai

After 3 years of trying just about every method that have been discussed here I have found the one that I am most comfortable with and see the fastest growing results for growing bald cypress. Once the tree is about 1/2 inch in diameter, I transfer it to an Anderson flat with mostly inorganic...

www.bonsainut.com

I will definitely have to try out your method . I've noticed BC seem to thrive in my climate to boot!

 

[Adair M]

A couple of comments: wooden grow boxes are excellent. You can use reinforced hardware cloth for the bottom. Wood doesn’t get hot like black plastic or even a ceramic pot does in the sun, so the soil acts more like soil in the ground.

Peter Chan letting roots grow two feet into the ground is a sign of neglect, not technique. He’s famous, but his videos promote poor bonsai practices. I think at one time he had the time to do bonsai at a higher level. But operating Heron’s doesn’t leave him time to really “do bonsai”. He’s having to operate a tree nursery, and it’s more than he can manage.

 

[sorce]

You're killing me Smalls....

Are we talking about more than Figs?

"So I shts on a thread."

The ground is way overrated.

The use of a proper root airpruning device at some stage of development is way underrated.

Show me someone with trees in the ground and I'll show you an impatient motherfu@quiere. Except @Shibui he's an observer, doing it right.

The benefit of fast growth is on a rapidly diminishing scale from an alternate elm to an opposite herbicided clusterfuq.

You'll faster grow yourself out of a good design than go unrewarded for patience.

If that don't make it in a signature line NO ONE is paying attention!

#puffkilledbig
#bigwouldn'tentertheroom
#pacwouldablowntheroomup

Sorce

 

[ShadyStump]

Here's the gist of the tree physiology at play here.
The growth hormones that encourage root growth are made in the tips of the branches when new leaf buds pop. The growth hormones that encourage top growth are made in the developing fiber roots- those tiny hair-like ones. These are also the portion of the roots that take up the most water and nutrients from the soil to send up with those growth hormones.
By planting a tree in the ground, there's virtually unlimited prime environment and larger woody roots for the fine roots to continuously develop, this feeding the tree more, and the tree grows bigger faster.

We can simulate this growing them in pots when we repot and trim the roots. This gets the old roots out of the picture so that new fine roots can grow, creating more growth hormone.
It is slower than ideal conditions in the ground, and more labor intensive of course, but this is half the purpose of repotting routinely.

The baskets and fabric pot allow the tips of the fine roots to dry out and die back some when they reach the outer edges. We call it air pruning. This effectively creates the same situation of root pruning during a repot, but more passively and you'll still have to repot on occasion, just less often, resulting in less stressors to the tree that could slow it's growth.

Another thing to keep in mind is that when we're keeping trees in 100% inert, inorganic substrate like many do, we're essentially practicing hydroponics. The substrate essentially exists just to prop up the tree and hold water and nutrient solutions.

Apply that and let us know what you come up with.

 

[FiggieSmalls]

Here's the gist of the tree physiology at play here.
The growth hormones that encourage root growth are made in the tips of the branches when new leaf buds pop. The growth hormones that encourage top growth are made in the developing fiber roots- those tiny hair-like ones. These are also the portion of the roots that take up the most water and nutrients from the soil to send up with those growth hormones.
By planting a tree in the ground, there's virtually unlimited prime environment and larger woody roots for the fine roots to continuously develop, this feeding the tree more, and the tree grows bigger faster.

We can simulate this growing them in pots when we repot and trim the roots. This gets the old roots out of the picture so that new fine roots can grow, creating more growth hormone.
It is slower than ideal conditions in the ground, and more labor intensive of course, but this is half the purpose of repotting routinely.

The baskets and fabric pot allow the tips of the fine roots to dry out and die back some when they reach the outer edges. We call it air pruning. This effectively creates the same situation of root pruning during a repot, but more passively and you'll still have to repot on occasion, just less often, resulting in less stressors to the tree that could slow it's growth.

Another thing to keep in mind is that when we're keeping trees in 100% inert, inorganic substrate like many do, we're essentially practicing hydroponics. The substrate essentially exists just to prop up the tree and hold water and nutrient solutions.

Apply that and let us know what you come up with.

Ooh yeees, this is the science I needed!

In that case, maybe there is additional benefit to growing roots in substrate below/around a basket in that only finer roots can penetrate through (assuming the drainage holes are more like a mesh, not big holes). Seems like the roots in the basket will continue to thicken while sending out lots of finer roots into the surrounding medium. I'll have to think about it, but I don't see a reason we couldn't apply the hydroponic concept quite literally in a gravel substrate to grow roots by just irrigating water and nutrients through the gravel. At least, during the summer. Not sure we'd want to run the water during winter...

 

[Shibui]

I grow both in ground and in containers.
There is differences with different species and there's lots of different possible approaches so try not to get hung up on the 'best' way.

Shallow pots are over rated IMHO. Deeper containers definitely hold water and temp better than shallow trays so plants usually grow better. We can correct roots by root pruning so deeper pots are still OK for developing bonsai. Wooden grow boxes also give great results.
Trees will definitely put on a burst of growth if roots get away into the ground under the container. That's sometimes OK but occasionally one or 2 roots will get there first and take off meaning the nebari will be uneven. Very occasionally after a few years into the ground, the roots in the container decline and the tree relies on the roots in the ground so transplant and root reduction can be difficult when that has happened.

I'm currently getting increased growth from shimpaku juniper in pots in pots. The original pot of potting soil is placed into a larger pot of plain gravel, slightly sunk into the gravel enough to hold it stable.

My initial thought is if I did a pot on top of a pot of just gravel, the gravel would dry up pretty quickly

My results would disagree with your theory. When the trees are watered daily through summer there's plenty of moisture in the gravel so roots grow well with a corresponding increase in trunk growth.
Growing in containers may be a little slower but the results are usually better in the end. It is still possible to develop great bonsai from seed or seedlings so if you don't have access to ground don't be put off. Get some trees into grow containers.
Ground growing has the potential to grow fast but also potential to develop bigger problems.
Growing in containers allows you more opportunity to intervene and make adjustments to head off possible problems.
Taper tends to be better, less scars to deal with or hide and far better branching and ramification in container grown bonsai.

Don't overthink it. A tree in a container is not a commitment for life. You can change the container or your approach each spring if you see another possibility but they won't start growing until you start planting. I'd encourage you to have a go.

 

[Driftwood]

Excellent post, could some one plz explain more about up poting size, what media and if better using 'the tile method'' at the same time? Also if needs root work, does it has to go back into smaller pot and continue the cycle until grows a desire nebari/trunk size? Graham potter also talk about it on ''how to Bonsai quick results pt1''.Thank you.

 

[ShadyStump]

When up-potting you go up as much as you need. Just remember that the more space you give the roots, the more you'll have to eventually cut back, putting more stress on the tree.

Using finer grained media will help hold more moisture than a larger particle size of the same material, and also creat more of the finer roots. Coarser media leads to bigger thicker roots, and won't hold as much moisture.

Whether or not to use a tile depends on what you're trying to accomplish with the roots at the moment.
Generally, finer media is used in early stages in order to encourage the fine roots that encourage growth; and coarser media is used in the later stages.
Development of nebari generally means coarser media, which means slower growth.

These are just the general guidelines, of course. You're goals and expectations will dictate what you use when and where.

 

[Shibui]

Excellent post, could some one plz explain more about up poting size, what media and if better using 'the tile method'' at the same time? Also if needs root work, does it has to go back into smaller pot and continue the cycle until grows a desire nebari/trunk size? Graham potter also talk about it on ''how to Bonsai quick results pt1''.Thank you.

Sometimes small plants roots cannot colonise a really big container quick. It seems the soil then goes bad and can sometimes kill the plant. Better to start smaller and move the plant up a size when the roots have grown enough to fill the previous container. Commercial growers tend to go up a couple of pot sizes each time and that allows for better root growth.
Potting media depends on how you manage the plants. Each grower will have a different 'better than anyone else' mix that suits how they grow in the conditions they grow in. As a general rule, the larger the container the less critical the mix becomes so regular commercial potting mix is usually fine for deeper, standard nursery pots and containers. Special mixes become more critical for shallower bonsai trays but not so critical for growing on in larger containers. Whatever soil mix you use for growing on can be changed out for your special mix when the tree has grown. Most species have no problem with a complete change of soil.
Tile method is over rated IMHO and often used incorrectly. Good root pruning will do a much better job of producing great nebari.

Also if needs root work, does it has to go back into smaller pot and continue the cycle until grows a desire nebari/trunk size?

Not sure what you are asking here? After root pruning most trees will go back into the same container. I often move developing trees into a larger container after root pruning if I still need more growth. Nebari and trunk size is not so much about pot size, though bigger will accelerate development, nebari is a product of age, growth and directing roots by root pruning or some other methods.

 

[Ramman]

It is common to see people placing their trees in smaller pots on top of a larger pots or putting their flats directly on the ground to let the roots escape and grow down and accomplish this same effect. I think it’s @Cajunrider that grows bald cypresses in pots on top of larger pots all sitting in a water tub. He’s simulating swamp conditions to help his BC grow vigorously. The baskets are Anderson flats. It’s very common, as is pond baskets. You can find similar flats on Amazon.

 

[willis0686]

Took inspiration from this forum and went ahead and did a version of what was discussed. I used an aquatic plant basket, which I cut the bottom out of and replaced with window screen. The second container I simply cut the bottom out and added hardware cloth for drainage. I plan on sinking the plant basket about a quarter depth or so into the serving basket, and have lava rock for a medium. In the last picture there is a small container I plan on setting the second basket in, that will hold a small amount of water for even better moisture retention. Open to thoughts and suggestions!

Will post more pictures when I am able to plant.