I was talking to a friend who is a real soil scientist.(He actually makes a living at it) He sent me this little guide to making soil. It's very easy to understand. It's a long read but it's worthwhile. Hope you all enjoy.
Happy Bacteria A Company Solving for X in Agriculture
Friday, October 2, 2015
- Organic soil can be recycled over and over and over and over. In fact, it gets better over time.
- Organic soil amendments take a long time to break down, some take years. Far longer than a grow. A plant uses a small amount of the elements available. Therefore, there is still significant amounts of elements still present in the soil. Soil can be used for several grow cycles without any additional amendments
If your garden is No-Till, then don't follow this. Just Top Dress with some extra goodies every so often.
Revitalizing your soil is an Art not a 'Science'
The suggestions I make here are good. However, it's not a science and your plant may require something a little different. If your plant showed any kind of deficiency, you will need to amend to correct. At the end of the day, trust your gut. Follow the formula
The
ONLY thing you should absolutely add more of is humus, plus whatever aeration needed to offset the humus.
Keep a supply of amendments in various stages of decomposition.
Lightly re-amend after each grow.
After harvesting - pull out the root ball. The stuff hanging onto the roots is bacteria and fungi. Dump the remaining soil into a suitably sized container.You can either chop up the root balls and mix with other soil. If your grow container is big enough, just use the root ball as a filler.
Amending
Compost / Worm Castings aka Humus - 1 part of Humus / 4 parts of old soil
Aeration - ½ of total humus added. If you added 10 gal of humus add 5 gal of perlite or rice hulls - similar
Kelp meal - 1 cup per Cubic foot of soil
Dry organic fertilizer - ¼ ~ ½ cup per cubic foot of soil
Lime - sweeten with ¼ cup per cubic foot of soil
Non-Cook formula:
You don't have to sit and let it cook unless you added any extra amendments if you added, you wait.
If you add anything "extra" or more than ½ cup of dry organic fertilizer per cubic foot you will need to let it cook for 2~4 weeks prior to use.
Nuggets of Info
This is the time when you can add any new amendments you want to add. I suggest you add 1~1 ½ cups of additional amendments. You will need to allow the soil another 2~4 weeks of cooking to allow the amendments to break down.
Let's say that you started with the base soil amended with only kelp meal and dry organic fertilizer, and now you want to several "extra" amendments (or just one, whatever you like). Make a blend of all the amendments you want to add, using equal portions of all amendments with a double portion of kelp meal. Now add 1-1.5 cups of this mix to your organic soil and allow to cycle for 2-4 weeks, or more (the longer the better).
Soil Phases
Soil has 2 very distinct phases. Solute and Solid
Solute
In this phase we talk about Nutrient Cycling. - Bacteria and enzymes work to both build up and break down the elements/ compounds. The resultant viscus bacterial slime serves as the liquid from which both the plant(s) and members of the microHerd absorb nutrients.
Solid aka C.E.C. Cation Exchange Capacity
The 'AAA Farm Club' or Reserves. For example: The Ions of a nutrient absorbed to the soil's CEC cannot be stripped or leached away with water, even lot and lots of water. These Ions are held in the soil by a electrostatic charge ( + ) and are available to the microHerd and can pass across the root membrane and into the plant.
So now the light bulb goes on and you create a soil 'mix' that is very high in O.M. (organic matter) At this point in time, you need to consider how you are going to sweeten the soil to offset the the bacterial action. Remember, bacteria secrete very powerful acids and over time these acids will cause the soil pH to drop.
Making Soil Sweet
So, we got this high OM soil but didn't put anything in it to offset the bacterial action. This is where lime, gypsum, etc come in. When plants and/or members of the microHerd strip/absorb the Nutrient (+ charged) cations from the 'soil solid' (- charged cations) OR from the Solute, they exchange them for Hydrogen ions (+ charge)
The vast majority of nutrient ions are Cations, then the net change of the soil's pH will trend towards acidic over time. We have to neutralize this. This is where liming agents enter the picture.
Deep End of the Pool
Liming agents Neutralize Hydrogen in solution, thereby negating their influence on soil solution pH. The Solid phase (C.E.C.) also has the ability to 'buffer' the pH of the soil by absorbing hydrogen out of solution and 'binding' it so that it no longer has an effect on pH, and ultimately nutrient uptake by plants and microbes.
Petticoat Junction
With a high OM soil mix, you have very little to neutralize free hydrogen in the soil solution. The only OTHER place that it can go is to the soil's CEC. After a few grows in the same soil, your CEC is probably "full" of hydrogen ions, and is no longer able to buffer H+ out of the soil solution. That being said, the soil solution (where plant/microbial nutrient ion exchange happens) is also saturated with excess soluble hydrogen. pH is nothing more than a measurement of the concentration of hydrogen ions in solution. Think of this concentration as "x" amount of hydrogen ions in "x" amount of space. If the available "space" is filled with mostly hydrogen ions (+), they tend to REPEL nutrient cations (also +) so that they are unable to be adsorbed by the negatively charged nutrient adsorption sites on the plant root. This is how/why low pH results in nutrient "lock out".
Adjusting pH
Generally speaking farmers, both Organic & Conventional use either sulfuric or citric acid as their buffer (sweetner). Both are approved NOP. 'High End' 'Professional' soil mixes (Sunshine Organic Grower's Mix) generally use gypsum as their sweetener. It is used as the coagulate in soy milk, so we know it's safe. Gypsum - calcium sulfate with the formula CaSO4. Elemental Calcium (Ca++) Sulphur with 4 oxygen atomsAs we already know, Calcium (C++) is a base alkaline. This means it can, if need be, be utilized by the microHerd to lower the pH of the soil. -Sulphur is broken down by the microHerd as well and this produces sulfuric acid.
The Cations in the soil which affect the soil's pH carry a ' + ' charge, which means it is held in the rhizosphere by the ' - ' charged ions, eg: humic & fulvic acids along with clay particles. These acids come from your EWC & compost. This electrical charge dynamic is what literally holds the 6 basic soil cations in place even when you flush with water.
6 Basic soil Cations: Alkaline
Magnesium (Mg++), Calcium (Ca++), Potassium (K+), Sodium (Na+)
6 Basic Cations: Acid base
Hydrogen (H+) *it's the Hydrogen (H) that is the 'H' in pH * , Aluminum (Al+)
Electrical charges
When plants are exposed to massive amounts of water (flushing), very little minerals are being removed because:
- They are held in place first by this electrical charge.
- Secondly by the slime the bacteria create which envelopes the minerals, humus, and such.
Chemical products
These products carry a Negative charge. Look at the ingredients in a chemical "Fertilizer." Check the wiki and you'll see each and everyone carries a ' - ' Negative charge. What this all means is: when you apply enough water to get some kind of run-off, the negative ions are removed from the soil. This 'run-off' tells us absolutely nothing about the soil pH and even less (if it's possible) about the water's pH. It is totally nutz on any level. Forget science, it doesn't even pass the logic test.
To test soil pH
If you want to test your soil's pH then dig down a couple of inches and collect a tsp. or so of soil and make a slurry with a known water source (purity, pH, blah, blah, blah) and then measure that. At least now you'll have some basis to make whatever adjustments you feel are warranted.
The real way to test the health of your soil is to remove a large fan leaf from the plant with a substantial stem from the stalk to the leaf. Take that opening on the cut and measure the plant's pH - it should be a 6.4 pH which is the same level in the saliva of a healthy person.
A fad?? OK, sure. Longest lived fad in human history besides the use of fire and shelter. A fad. Sheesh.
if been doing a lot of reading over the last bit and would like to ask a little advice before I jump in the deep end! 
Jeff 
