Why not make growing media with builder grit + garden Soil

Nishant

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Hello Friends,

I was just wondering as to why I could not use just the ordinary builder grit and garden soil as growing media? Grit will keep the aeration and drainage and prevent compaction, while the soil will provide the nutrition? The grit never breaks down and when it comes to repotting, tapping off the media shouldn't be difficult, I believe/

Do we necessarity have to think in terms of Akadama and pumice and lava and ...

Please advise and share your thoughts/experiences on this? BTW, I have to arrange for a good amount of growing media for my pine.
 
I call it rocks and dirt. And it works.
Same as 8mm balls and compost, only less exact.

I wouldn't use it in a container prone to cracking in a freeze if froze though.

Sorce
 
Thanks Sorce for reply? Does grit hurt in anyway? Have you used it yourself. I will be using it on a pine and the planter will be a wooden planter with the walls 1 inch thick.
 
Garden soil will stay way too wet for too long.
Builder's grit isnt pourous and doenst retain moisture and nutrients like Akadama, pumice and lava
A mix as you describe will be heavy and make pots heavier and more work to move around

I used pure sand and gravel when I started cause I didnt want to "spend money on dirt"
Even with sand and gravel, it stayed too wet for too long.
It was extremely heavy to move around
It compacted and didnt allow for good root growth.

I changed to pumice and lava for trees in early development and add akadama once they get into smaller bonsai shaped pots.
The health and root growth of my trees showed how much better that mix was over a heavy, compacted mess that sand and gravel was.
 
Hello Friends,

I was just wondering as to why I could not use just the ordinary builder grit and garden soil as growing media? Grit will keep the aeration and drainage and prevent compaction, while the soil will provide the nutrition? The grit never breaks down and when it comes to repotting, tapping off the media shouldn't be difficult, I believe/

Do we necessarity have to think in terms of Akadama and pumice and lava and ...

Please advise and share your thoughts/experiences on this? BTW, I have to arrange for a good amount of growing media for my pine.


@Paradox - covered the problems with this type of mix very well. Prior to the 1970's this mix was in common use for bonsai in North America. Then people like Bill Valavanis and others began importing Akadama and Kanuma from Japan, and began seriously studying the theory and practices behind potting materials. The blend will work if you are careful about your watering, but the results will be inferior to other products.

The single best component for a bonsai mix is pumice. If you can not buy anything else, do spend the money to get pumice. Perlite is a fair substitute, but perlite is too light for use in shallow bonsai pots. Perlite is excellent in grow out containers, where minimizing weight is important.

Pumice is one of the few components that can be used at 100% for a range of species. It works by itself or in conjunction with other products.

If you understand how to water and fertilize with a particular mix, you can grow a tree in just about anything, even chunks of old automobile tires. But you will have better, more consistent results if you use one of the modern substrates. The modern substrates allow for a greater margin of error, the timing of your watering does not have to be as precise. Your fertilizer choices are more open. You can get away with going longer periods between repotting with modern substrates. With the old grit & garden loam mix, you have much less tolerance for errors.

Akadama, pumice & lava, is the current "gold standard". But there are many, many other mixes that are used to good effect. Read Michael Hagadorn's book "Bonsai Heresy" published in 2020 for a good explanation about why the Akadama-Pumice-Lava blend is superior.

One item that improves all bonsai mixes, no matter what you use. It is sifting for uniform particle size. As much as possible, you want all the particles to be the same size. Sift to remove fines and sift to remove coarse particles. This will greatly improve root health, by keeping air voids open in the mix. The type of sieve I am referring to is in the link below. All mixes, commercial or home made will be improved by eliminating fines and overly coarse particles.

 
I have been experimenting with Grodan Grow wool,#2&#3 perlite,course vermiculite.
Ok Akadama is nice,ther is alot to be said about using the hydro media in our bonsai media.
Especially when they are anchored properly like I have been shown.Loose media can be held together better when you incorporate rockwool layers or strands of fibers through it from the grow wool.
I have used the small rockwool cubes in hydro pots mixed 50/50 with large perlite and them ones are more robust and I am feeding quite strongly.....just water well and use enzymes from the get go.
 
In addition to what others have said, garden soil is inferior even if you can somehow nail the watering regimen perfectly. This is because optimal root development happens when the roots have to do a little bit of work. If the roots are sitting in wet soil, they don't have to do anything at all to get all the water the tree needs. But root growth is stimulated when the pot dries out from time to time, in an ideal case, daily, for which you need a very well draining medium.

To illustrate, here's a common death scenario for seedlings planted in garden soil that stays wet. The roots never develop because they don't have to. Then one day in August you forget to water or it gets to 110 degrees and the seedling is baked to a crisp in one single day, and you're left scratching your head as to how in the world that could happen to a plant that had 4-months or more to grow roots. The issue is that it never had to.
 
Consider this. Most of us who have been doing bonsai for long enough (40 years for me) have tried just about everything, and most things will keep plants alive to varying degrees. But everyone I know with world - class trees uses akadama/pumice/lava. That's no accident, it is simply what works best to produce the best bonsai without any doubt.
When I started I was told to use pine bark and decomposed granite. Man were those heavy pots! and that mix held so much water that liverwort was the most common weed.
Then along came Turface. It kind of looks like akadama so it seemed like a good idea. Except turface is hydrophopic (repels water) and has a very poor ion exchange capacity. Roots grown in Turface were pitiful.
Believe me, I've seen people try a lot of things and so have I but I only now use akadama/pumice/lava in varying proportion depending on the needs and goals for each tree.
The one caveat with completely non organic soil is that it isn't the ideal habitat for soil microorganisms. That's why we use organic fertilizer... problem solved.
 
There are no rules, use what you want. The bonsai police arent going to come and arrest you.

That being said, most people use APL mix because it yields good results. There is always going to be some folks that swear by letting their trees grow in garbage, and I bet it works for them in their climate.
I bet you wont see many show trees in ditch dirt and gravel, however. If it was the “best” way,Im sure the most famous Bonsai Artists would use it accordingly.
 
Not sure the soil provides nutrition. The sun does and fertilizer aids....
Microbes would be the other 1/3rd of your equation.
I am doing deep personal study of the biome/rhizosphere.People love their organics because it feeds this.
Although you can create hydroponically so I am learning also.
When you get the root exudates feeding microbes and making the amino acid type of NPK .....available at roots ....it totally eases the load of photosynthesis ,so you can actually have a surplus of food in the plant....to create the suger/brix

The secret in hydro( so I am experimenting) is adding the carbon for your microbe innoculants to feed on.This is the Humic acids,kelp,and also I have added Cane Molasses to my nutrient recently for more of this process.And yes I do add a large amount of a couple specific ‘super star’ amino acids every watering.
Will add large course vermiculite at 25% for cec also to accentuate even faster!!!! This rhizosphere.
 
Look around for safe-T-sorb at tractor supply stores or somewheres

Its fullers earth, sold for absorbing oil spills,essentially baked clay ,cool alternative that ive really enjoyed using as inorganic substrate ingredient..and its cheap for a 40 or 50lb bag. Retains and drains

pick up different things,chef up a mix
 
I have been experimenting with Grodan Grow wool,#2&#3 perlite,course vermiculite.
Ok Akadama is nice,ther is alot to be said about using the hydro media in our bonsai media.
Especially when they are anchored properly like I have been shown.Loose media can be held together better when you incorporate rockwool layers or strands of fibers through it from the grow wool.
I have used the small rockwool cubes in hydro pots mixed 50/50 with large perlite and them ones are more robust and I am feeding quite strongly.....just water well and use enzymes from the get go.

Probably 30 years ago I tried Grodan's rock wool, both the cube and the loose form. At least the way they were made back then did not work out. Its been so long ago I forgot exactly why. Similar coarse vermiculite was something I used 30 years ago. It held too much water and was too soft to mix with anything other than very light media like pelite. Then the supplier I used was shut down due to asbestos contamination in their vermiculite. Wear a high grade dust mask when sifting vermiculite. I'm sure if they are currently in business, there is no asbestos, but it is one of the potential contaminants of vermiculite, at least in the bad old days.

I almost feel the urge to try again with these products, but then I look at the bags of pumice and akadama I have in the yard, and think, I don't really have the time to go back to experimenting.
 
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