Living organic soil from start through recycling

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SeaMaiden

That's what I'm asking, CC. I understand how it works in water, not quite as well in soils. I know that the Ca becomes available in a water column, I know that the CO3 keeps the water column alkaline (i.e. resistant to pH shift, which has quite a lot to do with CEC). What I don't know, or understand, is why you can get some Ca into solution in an alkaline water environment and you apparently can't in a soil environment.

Which is why I'm asking.
 
SeaMaiden

Hopefully the Horticulture School at Clemson University can help answer your question(s) (Dr. T.L. Senn, et al) - one of the oldest horticulture schools in the world, i.e. not just the USA

What is the use for the Cation Exchange Capacity (CeC) and the Percent Base Saturation on the soil test reports?

The CEC is the abbreviation for the Cation exchange Capacity of the soil. Any element with a positive charge is called a cation (pronounced cat eye on and not ka-shun) and in this case, it refers to the the basic cations, Calcium (Ca+2), Magnesium (Mg+2), Potassium (K+1) and Sodium (Na+1) and the acidic cations, Hydrogen (H+1) and Aluminum (Al+3). The amount of these positively charged cations a soil can hold is described as the CEC and is expressed in milliequivalents per 100 grams (meq/100g) of soil.

The larger this number, the more cations the soil can hold. A clay soil will have a larger CEC than a sandy soil. In the Southeast, where we have highly weathered soils, the dominant clay type is kaolinite which has very little capacity to hold cations. A typical CEC for a soil in the Coastal Plains region is about 2.0 meq/100g of soil and the typical CEC for a soil in the Piedmont region is about 5.0 meq/100g of soil. The CEC gives an indication of the soils potential to hold plant nutrients. Increasing the organic matter content of any soil will help to increase the CEC since it also holds cations like the clays. Organic matter has a high CEC but there is typically little organic matter in our soils.

The Percent Base Saturation tells what percent of the exchange sites are occupied by the basic cations. If Calcium has a base saturation value of 50% and Magnesium has a base saturation value of 20% as shown above, then Calcium occupies half of the total exchange sites (CEC) and Magnesium occupies 20% of the total exchange sites (CEC). In our example where the soil has a CEC of 5 meq/100g, 2.5 meq/100g of the CEC is occupied by Calcium and 1 meq/100g of the CEC is occupied by Magnesium. If all the exchangeable bases (Ca, Mg, K and Na) total 100%, then there is no exchangeable acidity.

The acidity on the report is the amount of the total CEC occupied by the acidic cations (H+1and Al+3). The acidity, like the CEC, is expressed as meq/100g of soil. If the CEC is 5 meq/100g of soil and the acidity is 1 meq/100g of soil (see sa mple above), then one-fifth of the exchange sites in the soil are occupied by acidic Hydrogen and aluminum ions. The remaining 4 meq/100g of soil (or 80% of the CEC) will be occupied by the basic cations. The more acidic a soil is and the lower the soil pH value, the closer the acidity number will be to the CEC number.

You can see a detailed explanation of how the CEC, exchangeable acidity, and percent base saturation are calculated from the routine soil test data.

Sodium is included among the bases to indicate if sodium levels are getting too high. This happens in situations where industrial by-products are applied to the soil or where soils along the coastal region are irrigated with water high in sodium. The acceptable base saturation limit for sodium is 15%. This is also called the Exchangeable Sodium Percent or ESP. Sodium levels higher than 15% on the exchange site could result in soil dispersion, poor water infiltration, and possible sodium toxi city to plants.

The next step to understand this is the 'why' that Calcium is written as Ca++ whereas Magnesium is written as Mg+ - this has to do with the 'exchange sites' meaning that a single Calcium ion (Ca++) can be exchanged for 2 Hydrogen ions (H+)

That is how pH is maintained in the rhizosphere - microbial activity breaks the bonds on Calcium Carbonate releasing Carbon and Oxygen (O3) into the soil thereby freeing the elemental Calcium.

That's how the boar runs through the buckwheat here in the Shire......

Bazinga!

LOL

CC
 

Scrappy4

senior member
SeaMaiden, I posted this is the EJ thread recently but I think it's worth posting here since were talking PH in soil now. This little ditty has helped me better understand what is going on in my soil as far as PH is concerned.

And on a practical level my gardens have improved since I left dolomite lime behind for a more diverse cal mag arrangment.



Soil Biology and pH by Jeff Lowenfels

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.
 
SeaMaiden, I posted this is the EJ thread recently but I think it's worth posting here since were talking PH in soil now. This little ditty has helped me better understand what is going on in my soil as far as PH is concerned.

And on a practical level my gardens have improved since I left dolomite lime behind for a more diverse cal mag arrangment.



Soil Biology and pH by Jeff Lowenfels

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.
Make Scrap's post a stickie - please
 
S

SeaMaiden

Both posts should be stickies, and maybe this whole THREAD should be made sticky.

This is rather different from water. It's stuff I've read before, requires me to re-read and is actually most easily absorbed into my brain if I have it in hardcopy. I don't understand why that is, especially as I love eBooks, but there it is.

*Will* re-read, in the hopes that I begin to grasp why I can get Ca into the water column when keeping fish, but can't do quite the same thing without other adverse effects in soil. Since I am working with soils that are known for their low fertility and Ca content, this is very important. It's easy to get organic matter into soils, but getting the right balance of minerals is a bit more difficult. Especially if I have to perform mathematical equations.
 
SeaMaiden

Run 'Chemistry Solubility' through Google Scholar, SCIRUS or JSTOR - the answer is there for the 'how & why' on water vs. soil uptake

Looking to amendments to get your soil 'right' is fraught with problems. Get the humus component in your soils dialed-in and you won't have to worry about CeC, mineralization, 'nute' availability or any of the other myths pushed at Hydro Heaven.

CC
 
Scrappy

So back to the original question (or something close) - have you used straight Sphagnum vs. one of the base products like Sunshine Mix(es) or Pro-Mix?

Part of the acidity issue can be directed back to this base material.

CC
 
S

SeaMaiden

SeaMaiden

Run 'Chemistry Solubility' through Google Scholar, SCIRUS or JSTOR - the answer is there for the 'how & why' on water vs. soil uptake

Looking to amendments to get your soil 'right' is fraught with problems. Get the humus component in your soils dialed-in and you won't have to worry about CeC, mineralization, 'nute' availability or any of the other myths pushed at Hydro Heaven.

CC

Ah, it's building up that humus component (organic matter) that I've been focused on. In reading up on getting my soils tested I learned that because I haphazardly applied different sources of Ca, that will make getting an accurate Dx via soil testing that much more difficult. Apparently I can NOT do it the same way as how I cook, which is to say it is almost purely by feel.

I don't use hydro stores, let alone for my source(s) of information, though I'm sure that I'm still wasting money using many of the sources I do, but I'll learn, I always do. :)

P.S. Familiar with GS, Scirus, but not JSTOR. Who, where, what? I have an acquaintance who's a research assistant and she was astonished at what I could find her using Google Scholar for free, and that she was PAID FOR! All she needed was to find the citations on a certain paper and I found them for her in minutes after she'd been working days on it.
 

Scrappy4

senior member
Scrappy

So back to the original question (or something close) - have you used straight Sphagnum vs. one of the base products like Sunshine Mix(es) or Pro-Mix?

Part of the acidity issue can be directed back to this base material.

CC

Yes, in my last soil mix I used premier brand peat, to be fair there was a small amount of used pro mix. The premier mix is just sphagnum peat with no additives that I am aware of. It had a PH of 5 at the start. I added my inputs, that i listed earlier, wet it with compost tea, and left it set for months, wetting it with water when it dried out, and when I did check the PH, like magic it was 6.5.

Same thing in my compost heap. No matter where it starts it ends up around 6.3 to 6.6PH.

Nearly the same thing in my yard. My soil is always around PH 7 to 7.3. Where I live was an ancient sea bed, so we have an abundance of Calcium from old sea shells and coral. Anyway at times i tried to lower the PH around berry bushes, rhubarb and what not. I added a layer of premier mix about 3 inches deep then covered it with thermo compost. I tried again last fall, this spring it's at 7 again. Now I gave up trying to change the PH, the berry bushes are fine, so i guess I was trying to fix a non problem. Even though everything i have read says those berries need low PH, go figure......scrappy
 

Gascanastan

Gone but NOT forgotten...
Take a quart jar and put in a handful of regular non-adjusted peat moss...and in another jar put a handful of name brand peat moss...

...now fill the jars with water and shake. Let it sit an hour or two and then take the standard issue Ph meter and take readings...

The regular Peat Moss should be around 4.0

The various name brands will have different readings floating from 4.5 to 7.0 depending on batch and 'name' of the product.

This is the reason why I've pushed and used the 3-way lime mix based off Steve Solomon and Coot. ....no matter what brand of peat moss I use.

It's hard to really over-lime peat in a proper organic soil from my experience..considering you follow the 1 cup lime mix per cubic foot of peat rule-o-thumb.

I'm confident that I could now actually replace dolomite with oyster shell powder..and not worry my aching little heart over it.
 
Scrapp

If you have the package material from the Premier Peat still around I was hoping that you could tell me where it's packed. That information is required under Canadian and US laws.

I think that Microbeman figured out something in a post he made on another thread where he tested Sunshine Mix and compared the results when he ran Premier Peat and maybe even when he did me a favor several months ago and tested the Alaska Peat.

Thanks!

CC
 
P.L. Light Systems - HSE

Available with your choice of 18 reflectors depending on what your garden situation requires

HSE600W_3_72dpi_RGB.jpg
 

Gascanastan

Gone but NOT forgotten...
I use the Alaska peat...seriously a nice offering for organic soil builders. It looks un-molested and smells 'active'...for me it's the good stuff.
 

Gascanastan

Gone but NOT forgotten...
P.L. Light Systems - HSE

Available with your choice of 18 reflectors depending on what your garden situation requires

View Image


How cool does it run?...or how hot I should say.

Can you touch the ballast compartment without burning skin?


......ooooooo member of Hortilux. not really riding the snake oil band wagon eh
 

Scrappy4

senior member
Scrapp

If you have the package material from the Premier Peat still around I was hoping that you could tell me where it's packed. That information is required under Canadian and US laws.

I think that Microbeman figured out something in a post he made on another thread where he tested Sunshine Mix and compared the results when he ran Premier Peat and maybe even when he did me a favor several months ago and tested the Alaska Peat.

Thanks!

CC


Sorry the peat bag is long gone. I seem to remember it was from western Canada. The other main brand of peat in my area is lambert peat, and if it helps, it is from Quebec. Lambert makes a whole line with both amended and unamended. As far as I can tell they are very similar, with no obvious differences, at least none that I have noticed.....scrappy
 
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