Growing question

[Necrosis]

I have a few bonsai I'm currently growing. They are mainly in nursery pots and soil. Should I be using bonsai soil in these containers to grow them or just leave them in the pine bark mixture they are currently growing in?

 

[Orion_metalhead]

The irony of a user named "Necrosis" asking about "growing".

All depends on the watering habits, i would say. You may get some finer root growth bonsai soil. Put your location in your profile so others can give you best advice based on climate!

 

[Necrosis]

Decay and growth are two sides of the same coin

 

[Shibui]

Not all bonsai soils are the same as you will no doubt discover. Everyone uses a slightly different mix and theirs is 'definitely the best' so there are bonsai growers growing very good trees in all sorts of mixes. Reality is that trees will grow in a wide variety of potting mixes. Just because you decide you are going to make bonsai does not change the tree's needs. You said the trees are in 'soil'. Is that garden soil or some other potting mix? Garden soil in pots can cause problems as it does not drain well in pots. You may be able to get away with that in the short term but problems will inevitably occur. Potting mix is designed to meet the needs of plants in pots.

You can get away with less quality mix when trees are in deeper containers but when you start to use shallower containers there is some need to use better quality potting mix that can manage to provide for the tree in small pots. That's when good quality 'bonsai' mix becomes more important.

 

[Leo in N E Illinois]

If you understand when and how to water the potting media you choose to use, you can grow trees in just about anything. I used rubber automotive tire chips as a component in a potting mix for a few years, they were free.

If you have your watering right, bark mixes are not evil. But if you water your trees in a nursery mix as often as trees in straight pumice, they will rot away. The potting mix has a big influence on how frequently you need to water, and what fertilizer you use.

 

[Necrosis]

To answer y’alls questions they are currently growing in a nursery potting mix with pine bark. I’m starting to think about repotting. My goal is to maximize growth. I’m unable to plant all of the my bonsai on the ground. I’m thinking about building some growing boxes. Is there a popular soil mix that suits this purpose? Should I just stick with akadama/pumice/lava?

 

[Bonsai Nut]

First of all, welcome to the site!

Second, our answers depend a lot on where you are currently with your tree(s), and where you are planning to go. We will give you different advice if, for example, you are growing a bunch of pine seedlings, than if you are trying to develop some Chinese elms that already have 2" thick trunks.

Take a few photos and don't feel afraid to share them. We have people that are growing everything on this site from brand new seedlings to very expensive exhibit trees... with everything in between.

 

[Leo in N E Illinois]

While you can grow in just about anything, if you understand when to water and how to fertilize, most successful mixes have one common component. PUMICE. Pumice is the single best ingredient for all bonsai mixes. Most mixes run from 25% to 75% pumice. Usually for deciduous, less than 50% pumice, usually for pines over 50%. There is wide variability, but the best, most widely used mixes have a significant amount of pumice.

Second is no matter what you use, a sieve to sift the fines out of your mix is essential.
The more uniform the particle size, the more air and water the mix can hold. Better root growth. It doesn't matter what the components of the mix are, the more uniform, the better. Get rid of fines, get rid of big chunks.

Akadama and Kanuma and other imported media are expensive and depending on where you are, may or may not be easily available.

Diatomaceous earth is popular, it is an all silica product. Turface is a mined clay, fired to retain structure, quality varies.

Single component media tend to be inferior in performance to mixes.

Try not to have to many different mixes, it will confuse you when it comes to knowing when to water what. Pick one or two different mixes, then learn how to water and fertilize them.

 

[Shibui]

Try not to have to many different mixes, it will confuse you when it comes to knowing when to water what. Pick one or two different mixes, then learn how to water and fertilize them.

My thought exactly
And pretty much the same for the rest of the info in that post.

 

[Necrosis]

Thank y'all for the responses. I found these articles particularly helpful for anyone else that is wondering about the same thing.

Soils for Containers and Bonsai

Aging of Container Soils

Why the Earth Is Not Like a Pot

 

[MrWunderful]

If you want to maximize growth, then you want to plant in ground if possible. Ground growing fully organic soil is fine.

My preference is anything in a container gets the following:

Deciduous- 1:1:1 akadama, pumice, lava with some pine bark and 8822 thrown in

Conifer-1:1:1 akadama, pumice, lava

Succulent: 1:1:1 lava, pumice, 8822

Those are what works great for me in my area.

 

[Necrosis]

If you want to maximize growth, then you want to plant in ground if possible. Ground growing fully organic soil is fine.

My preference is anything in a container gets the following:

Deciduous- 1:1:1 akadama, pumice, lava with some pine bark and 8822 thrown in

Conifer-1:1:1 akadama, pumice, lava

Succulent: 1:1:1 lava, pumice, 8822

Those are what works great for me in my area.

This is probably a dumb question but could you explain your reasoning for the variations in your soil based on the types of trees you have? Does the 8822 and pine bark hold more moisture? In general do deciduous trees require more water than conifers?

 

[MrWunderful]

This is probably a dumb question but could you explain your reasoning for the variations in your soil based on the types of trees you have? Does the 8822 and pine bark hold more moisture? In general do deciduous trees require more water than conifers?

Yes, pine bark and 8822 hold more water.

And Yes, generally deciduous like it wetter than conifers because of the amount of transpiration and resource movement of them -however, there are always exceptions.

I also use 8822 as a cheap akadama alternative, I only use actual akadama in mixes for final pot bonsai. I cant bring myself to use real akadama in training pots. I still throw some 8822 in refined bonsai mix because I like the particle size.

 

[JoeH]

Answers would be easier if you would share what trees you are growing out in nursery pots.

 

[Necrosis]

Answers would be easier if you would share what trees you are growing out in nursery pots.

A handful...

Standard Juniper x3
JBP
Japanese boxwood
Texas Cedar
Huisache
Bald Cypress
Texas Ebony
Ficus (ginseng?)