Clay as soil conditioner

[Jerry Smith]

Kris

I think you are right. Its been a while since I've read the article. Makes me now realize I don't need to add water to the clay mixture I make. But the water does cut down on the dust. No need to breathe in all that silica. I was thinking he was doing something else to the clay to "sweeten it up a bit."

I had some of the same problems finding clay years ago. I bought the air dry stuff and found out it was the wrong stuff. Got frustrated and got a recipe for a brick red clay body from a pottery site and modified it to "sweeten it up". This is what I used:

Part numbers are for items sold by: http://www.eceramicsupply.com/ This company is local for me.

2 lbs. Ball Clay Kentucky OM#4 (Old Mine #4) p/n OM4
5 lbs Goldart Cedar Heights clay p/n Goldart
5 lbs Redart Cedar Heights clay p/n Redart
2 lbs Espoma Greensand sieved through a fine screen
1 lb G200HP Feldspar p/n G200
0.1 lb Dolomite powder p/n Dolo
0.22 lb Red Iron Oxide p/n Ironspec
3.85 lbs Water.

Seal it all in a joint compound bucket so you don't breathe the dust. mix until it is all wetted then get in there with your hands to finish it off. You can adjust the water. I just went until it looked like clay from my memory.

I have mixed this up twice now. Next time I may modify it and add more nutritious clays. The Greensand is a substitute for Grog. Not needed in an aquarium for fertilizer purposes. I used the finest particles I could get by screening.

[krisw]

Very interesting -- thanks for your recipe, Jerry! I'm not familiar with Grog -- what purpose is it serving if not for fertilizer purposes? Or, is this just to thicken up the brick recipe, but could be omitted?

[Jerry Smith]

Kris

I am not a potter, but Grog is added to the clay formula to change the properties when it is fired. Grog is fired clay ground into small particles. Beyond that, I don't know. From the clay formulations I have seen, not all of them contain Grog.

[Ghazanfar Ghori]

Why the Feldspar?

[Jerry Smith]

Why the Feldspar?

When I was looking to make my second batch, I wanted to add some more Potassium. The Feldspar I used has 10% K2O. But I did not consider if it is soluble/plant extractable. That is a big oversight. I have hopes of finding out what the actual available nutrients are for this clay.

This is the composition of the Custer Feldspar:

SiO2........68.50%
Al2O3......17.50%
Fe2O3.....0.08%
CaO.........0.30%
MgO........Trace
K2O........10.40%
Na2O......3.00%

L.O.I.......0.30%, Loss on ignition- something potter's need to know.

I attached a pdf of the chemical composition of various items used by potters in making their clay bodies.

[SCMurphy]

When I say emulsify, all I am doing is making the clay into a liquid with water and added micros. I used to use Iron it until I saw the complete composition analysis. Now I just use the micro mix available for people mixing there own ferts or dry dosing. The potassium and dolomite are just scattered on the bottom of the aquarium before the soil is put down. You can either work the clay into the soil before putting it into the tank or pour it into the soil layer after. It's not rocket science by any stretch.

[Jerry Smith]

Thanks Sean. I needed that clarification.