Sourcing Organic Soil Mix Components

anyone have a line on oyster shell flour?
 
BAS is crazy expensive and KIS shipping price is really high.
groworganic.com wants $40 to ship $9 worth of flour lol..

 

Oyster shell powder/flour (pacific pearl etc) comes all the way from San Francisco. So I betcha shipping it cross country sucks no matter what. I'd go to the feed n seed stores and look for the crushed oyster shell.. used as chicken scratch.. pretty much the same thing..

Oyster Shell Powder - calcium carbonate (CaCO3) - This product is not what it would appear from the name, i.e. it's not a product made from crushed oyster shells but rather it's a particular oyster shell mined from the San Francisco Bay from ancient sea deposits made up of very tiny and fragile oyster shells.

Crushed Oyster Shells - calcium carbonate (CaCO3) and this product is made from crushed oyster shells. -LD

 

thanks holmes
 
but isn't one way more coarse than the other?
 
i think i want powder...
 
may just go w/ the crab shell if that's the case.

 

It's in Redmond, WA.. it'd be a road trip lol.... Concentrates in Oregon is probably closer.... I betcha there is decently priced Pumice in CA, though... or lava rock.... just a matter of finding it lol....

Yeah the crushed oyster is definitely more coarse. Idk.. ain't worth it for powder if it is 2x-3x the price. You could always grind up the crushed oyster with a coffee grinder or something....

Crab shell would do the job too. They're all full of Calcium. Your lobster compost will also have a good amount of Ca. And the worm castings..

 

 
The chicken scratch stuff is useless. Simply way too coarse and will not breakdown. Jerry and I both found out the hard way about that. I mean, when you're still finding chunks 3 years later it tells you something.
 
Why not get some Calcitic lime at Lowes or HD? Pretty much identical in makeup to OSF and cost a whopping $15 for a 40lb bag. Penningtons is the brand name and at HD it was right next to the dolomite lime, which is $4.50/40lb bag.
 
I've never seen crab shell indicated for use as a soil buffer. In threads, yes, but not from the manufacturers/suppliers. YMMV on that one.
 
Wet

 

but rather it's a particular oyster shell mined from the San Francisco Bay from ancient sea deposits made up of very tiny and fragile oyster shells.
 
I've heard coots talk about this twice now(I think even on the adam dunn show appearance), and he talks highly of it. Seems like it's really worth going after that certain material from the san fran bay.

 

 
yeah i think i'm covered between all of that.
 
plus i roast and grind a bunch of crab shell as well as using the coarse stuff.
was just thinking that if i switch from promix to a regular no frills peat moss, it doesn't have the added "liming agents" that the pro mix has.
but again, i think the crab shell, vermicompost and lobster compost will do just fine. (as you mentioned)
 
just liked the idea of oyster flower being added in.. but not at $40 shipping lol.

 

 
sounds cool wet..
 
i'll have a look.
 
you wouldn't consider crab shell as a calcium source?

 

Here's a cool coot quote on the subject...

"Just as a point of reference, my entire amendments for potting soil is limited to the following:

Glacial Rock Dust - 4 to 5 cups
Kelp Meal - 1/2 cup
Crab Meal - 1/2 cup
Neem Meal - 1/2 cup

This is used in a mix that contains 25% vermicompost.

No liming agents per se but I guarantee you that if you did a mineral analysis of my potting soil mix against any mix with all the Limestone, Dolomite Lime, Calcite Lime, Gypsum, Agriculture Lime, blah, blah, blah that one might want - I will come out on top if you were to do a real pH test as they do in labs, i.e. extracting liquid material from the branches or stalk. A plant's correct pH is 6.5 which is the same as human saliva, tears and perspiration." -LD

Liming agents are controversial... to say the least lol.... it's just Calcium.

Ca2+ ions adsorb to colloids in the soil, displace H+ ions, and that is what raises the pH of the "solid soil phase". pH means "potential Hydrogen" and is a measure of the concentration of Hydrogen ions [H+]. As the concentration of H+ ions goes up, pH goes down. As the concentration of H+ ions goes down, pH goes up.

The "effectiveness" of a liming agent has to do with its solubility. The more readily-soluble the item is, the more quickly it will have an effect on pH. Oyster shell powder and calcitic limestone are the two most soluble ones and will have the quickest effect on pH. Crab shell and crushed oyster take longer to break down. Grinding the crushed oyster shell or crab shell into a powder will increase solubility. I don't see how powdered, crushed oyster shell is really that much different from oyster shell powder...

 

As a calcium source, of course. But as a buffering agent, I'm not so sure.
 
Just like gypsum, I use it as a Ca source, but not for pH.
 
Wet

 

Hey now, wak those are my words lol... which I basically rephrased from that Michael Astera article on soil minerals. Great article btw. Have you read The Ideal Soil? Comes highly recommended from G45.

I've read a bunch of times that gypsum does not effect pH. We know that Ca displaces H ions from cation exchange sites, which is what raises pH. The reason gypsum "does not effect pH" is because it also contains Sulfur. This is converted to Sulfuric Acid by soil microbes. So I guess the idea is that the Sulfur kind of "neutralizes" the effect of Ca on the soil's pH. That is why gypsum "has no effect on pH".

This just goes to show that pH is not black and white. It is constantly fluctuating. Bacteria produce a slime that raises pH, fungi exude acids that bring the pH down. Plant roots exude H+ ions which bring pH down. It is always changing. There are sooo many things having an effect on pH all at once that it is mind boggling.

Use high quality humus, use a source of Calcium, and forget about it! Let the chemical growers worry about pH lol.

I've got a great quote from Mr. Lowenfels too lol

The success of the AeroGarden, the first plug-and-grow aeroponic kitchen appliance, is testament to the fact that ordinary people do not understand the concept of pH and don't want to deal with it in their growing situations. Make it so you can practice hydroponics without this chemistry barrier and they will come, apparently.

Frankly, the concept of pH also confuses soil gardeners. Heck, the definition of pH was inadvertently reversed in my book "Teaming With Microbes: A Gardener's Guide to the Soil Food Web." (Yes, some readers noticed; I received two "you made a mistake" notes. But that's not as many as I thought I'd receive.) Fortunately, the mistake was corrected in time for the second printing.

In any case, soil gardeners have been told certain plants require acidic conditions- for example, rhododendrons and azaleas- or else they won't grow. The solution advocated by most experienced gardeners is not dissimilar from what a hydroponics grower would do: adjust the pH with chemicals, such as agricultural lime, to make the soil more alkaline. To make alkaline soil more acid, we are told to add sulfur. Because they are chemical changes, these solutions work for a short time. But to me pH is a biological matter.

A bit of quick pH review is in order (if only to make amends for the mistake in my book). You may remember that pH is a measure of the acidity or alkalinity of a solution on a scale of 1 to 14; 1 being most acidic and 14 being most alkaline. A more technical description is that pH is the measurement of the concentration of hydrogen ions, H+. If you have lots of H+, the pH is low, or acidic. If you have few of them, the pH is high, or alkaline.

If you are adding fertilizers and using chemicals, you are stuck in the chemical realm. Organic gardeners, soil food webbies in particular, realize that pH has more to do with biology than it does with chemistry. That's because of the way plant roots take up nutrients. Root hair surfaces are covered with positive electrical hydrogen cations. Think of these charges as ping-pong balls. If soil particles are small enough, their surfaces are covered by these ping-pong ball charges, both positive (cation) charges and negative (anion) charges. These cations are not limited to hydrogen; they also include calcium, potassium, sodium, magnesium, iron, and ammonium. All are important plant nutrients.

When a root encounters a clay or organic particle, it can exchange one of its hydrogen cation for another positive one from the particle. It can choose from calcium, potassium, sodium, magnesium, iron, ammonium and hydrogen, as these are all cations carried by clay and silt and are all, as luck would have it, major plant nutrients.

This is known, incidentally, as cation exchange capacity, or CEC. Sand and silt have low CECs, because they comprised of particles that are too large to hold electrical charges. This is why humus and clay are needed to make soil good. They are extremely small particles and can carry cations.

So, back to pH. Every time a plant root exchanges a hydrogen ion for a nutrient ion, it increases the concentration of hydrogen ions in solution. Thus, the pH goes down and things should become more acidic.

Ah, but things usually balance out because the positive cations on the root surface also attract negative charges. Here, hydroxy ions (OH-) are the exchange ping-pong balls, and addition of hydroxy ions lowers the concentration of hydrogen ions in the solution, and pH goes up.

I know this still sounds like chemistry and not biology. However, each plant has an optimum pH requirement. What soil growers need to know (and hydroponics growers don't) is that the type of bacteria and fungi attracted to a plant's rhizosphere by the plant's exudates has a lot to do with setting this optimal pH. Bacteria produce a slim that raises the pH, and fungi produce acids that lower the pH. Since the plant is in control of the biology it attracts, in a natural system, it is the plant that determines the pH, and not some chemistry teacher.

So, while you may forget the chemistry of pH, at least remember there is a biological side. Do no harm to it, and you shouldn't have to worry much about pH when you grow plants in soil. Moreover, the nutrient exchanges that occur above also have a lot to do with what kind of bacteria and fungi are attracted to the root zone as some like higher pH and others lower pH.

 

 
cool post man..
that was the reason i ground up (and roasted) some of my crab shell. But i have to say.. i added some pretty decent sized chunks of crab shell into my mix as well and can't really see it in there anymore.. was just filling pots this AM, and there's no sign of the crab shell at all.
 
oyster shell.. i donno. Never used it but i'd have to imagine that larger pices (crushed) oyster shell would probably sit around in there for a REALLY long time as opposed to a powder.
 
as you know, i don't know shit about the science.. but yeah Ca would be Ca for the most part, no?
from what i understood the roasting of the crab shell convert the calcium carbonate into calcium phosphate, which is more bio-available. (forget who told me that one, it's in my thread somewhere)

 

At my local elevator they powder there crushed oyster shell for me. It usually has some chunks of corn in it too but i could care less.


CW

 

I think we needs a thread... pH: why it doesn't matter in living soil.... finally put this thing to bed....

 

WAK 
 
Yeah, Calcium is calcium is calcium and no argument there. In fact, I don't disagree with you at all, we are pretty much on the same page.
 
All I'm talking about here is calcium sources that haven't been indicated for use as a buffering agent. But, just because they aren't indicated doesn't mean they won't work. Some personal experimenting, experience, would be of benefit to whomever is curious.
 
I figured limestone is limestone. Doing a bit of reading shows me that not that many limestones are suitable for agricultural use. Who knew?
 
I have my mix just about perfect ... For Me. I've pretty much quit experimenting except with one ingredient or amount at the time. Whatever the results are, I only need to look in one place. Not like when I first started and trying 7 different things at once (an exaggeration, but not a big one). Trying to tell what worked, what didn't, was like a fools errand, because, which different thing do you look at? At one point I was using something like 11 different 'herbs and spices'. I've since cut back to 4 or 5, with much more consistent results.
 
(Not directed to/at Wak)  Anyway, AFA Crab shell, Lobster, or whatever, they bring a lot to the table besides Ca. Do they buffer? IDK, I've never used them for other than a Ca source. Try it/them and see, you'll be able to tell one way or the other. I DO know I've seen marked improvement after adding more Ca sources, but lime has always been part of the mix, so I can't attest to any buffering or lack of. I'm also too old to be roasting and grinding stuff, so you young guys have at it.
 
Wet