Inorganic planting medium help

GerhardG

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Hi All

3 years down the line I'm relatively happy with the soil mix I use, which is basically riversand from a specific spot with larger particles and misc. fertilizers mixed in depending on the tree in question.

This does come with some problems, and I want to go the inorganic route, at least with some trees.

Problem is none of the alternatives mentioned so many places are available locally.

Haven't found any suitable cat litter, all pet shops and department stores checked.

Can't get lava rock, nobody has and none are willing to order.(ALL local nurseries)

I can maybe (this will NOT be easy or cheap) get some LECA pellets from South Africa, but I don't know if they are suitable(?)

ANY other ideas/options?

Thanks
Gerhard
 

Bill S

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This could be a tough order to fill Geerhard not knowing much about your country. The thought I have is would there be a possibility of hard pan you could dig, similar to kanuma, akadama, or more recently Calidama from California??
 
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Can't you find just simple gravel of 4-8 mm ? There is less porosity than with pumice or lava rock and it is more heavy, but it works too.
 

Mojosan

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Crumbled hardpan wouldn't be much good unless you could fire it in a kiln. It would break down quickly under constant watering.

I would think that a sand base would be good. Sounds to me like you are already inorganic.
 

Bill S

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Crumbled hardpan wouldn't be much good unless you could fire it in a kiln. It would break down quickly under constant watering.

I would think that a sand base would be good. Sounds to me like you are already inorganic.


Tell that to users of kanuma, akadama, and calidama, you are correct though the larger particle sand will work.
 

Smoke

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But they are all hardened by firing, correct?

No, none of those are hardened by firing.

And it is clear you have never handled hard pan from the San Joaquin Valley. It is cement, plain and simple. PM me your address and I will send you a sample.
 

jquast

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No, none of those are hardened by firing.

And it is clear you have never handled hard pan from the San Joaquin Valley. It is cement, plain and simple. PM me your address and I will send you a sample.

Smoke,

Is your source for Calidama back up and selling material again?

Jeff
 

GerhardG

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Hi All

Firstly, thanks for the replies.

This could be a tough order to fill Geerhard not knowing much about your country.
Namibia is a huge 3rd world country (not bad as they go...) with only 2 million people, that means not a lot of buying power, and variety of available products suffers for that reason.
The thought I have is would there be a possibility of hard pan you could dig, similar to kanuma, akadama, or more recently Calidama from California??
My problem is these are all just names, frankly even pictures on the internet is not much use, I'll need to hold it in my hand if I'm to find an equivalent.
The whole country is covered with farms, which means access problems, likely drives to I don't know where to find suitable geology.....
Can't you find just simple gravel of 4-8 mm ? There is less porosity than with pumice or lava rock and it is more heavy, but it works too.
I could sift out particles that size easy enough, but I dare say the type of rock found here is not porous at all, and with our dry climate I think that could be a recipe for disaster, I have problems with the sand I use at times, my Elm recently dried out completely in the 9+ hours I was at work.
I would think that a sand base would be good. Sounds to me like you are already inorganic.

True to a certain extent, but I have practical problems with the sand I use, except for the drying out quickly. Our Acacias don't tollerate root work, so my 2 biggest ones were potted by drowning the nursery bag, squashing down the soil & roots as flat as possible and potting that mess - this has the effect that the trees grow on a little mound higher that the pot rim.
This combined with the sand is a constant issue while watering.

Thanks again, your answers has brought up a few more options I can try.

Cheers
Gerhard
 

woodguy

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Maybe look into aquarium gravel. It comes in many different sizes though maybe not in Namibia. It doesn't have the moisture holding properties of other things so you may need to add something to the mix so it doesn't dry so quickly.
 

GerhardG

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:D
Maybe look into aquarium gravel
I got a small bag of aquarium gravel that is ideal in every way, but it was only enough for top cover on two trees - the bag was 10+ years old.....
Local pets shops checked and found wanting:D

add something to the mix so it doesn't dry so quickly
Like bark chips? That I can actually get.

The replies made me think, might have to buy some cheap ficus and experiment a little.

Cheers
Gerhard
 

Mojosan

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No, none of those are hardened by firing.

And it is clear you have never handled hard pan from the San Joaquin Valley. It is cement, plain and simple. PM me your address and I will send you a sample.

No, I haven't - I'll take your word for it. It has always been my understanding that the "hard red" akadama was fired. :confused:
 

Dan

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I dont know the access you have to a field for burning brush but the product 'Turface' that I use (originally designed for baseball diamonds) is nothing more than clay fired to 1400 degrees F (760 C) as the clay fires it expands microscopically, these holes then act as water retention units. I don't know how long a fire would have to burn but if you made the sheet of clay thin and dry and sandwiched it between two pieces if sheet metal then built the fire on top it could work. If there is anyone on here that makes thier own pots they can probably tell you the time needed for a half inch (1.27 cm) thick piece of clay to bake for. Just a thought. If you have access to coconut husk this can be used with great effect to retain moisture but it is organic, it breaks down very slowly to in the US it comes chipped or shredded in compressed blocks. Terrarium growers have been using it for years to replace spaghnum ( can't spell LOL) moss as the means to hold water but not to much. Hope this helps let us know.
 

Dan

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The firing process lets the clay particles not break under frost conditions. If you don't have frost then maybe a cooler fire i.e. not as big would suffice. Again I refer you to the potters (not the wizards)
 

GerhardG

Mame
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Hi Dan

Thanks, I know a potter lady, I'll ask her.

I'm sure I saw cocconut fibres at a nursery recently, I'll take a look at that, more for spaghum replacement in airlayers (thanks!).

BTW, I've got access to a lifetime supply of compost, well broken down on the inside of the heap, but it's exclusively grass cuttings and thus very fine - always wondered if it's any good?

.......off to consider baking my own potting medium.....:D:D

Thanks
Gerhard
 

woodguy

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I would stay away from grass clipping compost. You would be better off with coconut husk in small pieces. Haven't used it for bonsai myself, but I have it in many of my orchids and it does hold up very well.
 

mrchips1952

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Turface

Have you attempted to find Turface which would work? It comes in 80 pound bags and I get mine at a commercial irrigation company that supplies sprinkler parts to contractors. It costs about $15.00 for the big bag. Dave / Colorado
 

woodguy

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Hi Woodguy

You confirm something I suspected, therefore the mention, I would love to know why(?)

Thanks
Gerhard

I suspect it would brake down too quickly. Where as bark or coconut will hold there structure for a longer period of time.
 
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