Substrates Hydro-Organic

substrates-featuredWhat is used and how they work together defines very important substrate characteristics such as root anchorage, water supply, nutrient retention, water level and air exchange.  Basic nutrition, most growers are fairly familiar with and are comfortable talking about. But the physics behind the substrate, is less understood by many. Surprisingly, when explained properly, the physics behind substrates is quite interesting and different from what one might have expected.

BELOW FIND UNIVERSITY STUDIES, LARGE CORPORATE RESEARCH, NOT TO MENTION NOTES FROM THE EDITOR

Substrate vs Compost

Substrate vs Compost

Don’t confuse “substrates” with “compost. The compost is but one of several ingredients in a substrate. A substrate is a mixture of 6 or 7 ingredients, which together, gives your container the below described characteristics. The compost is the ingredient which has all the nutrients. It is a pure “fermented” solid, organic material, decomposed and turned into dense fertilizer over 8 weeks time. This compost is one ingredient (25 to 30%) of the...

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Five Important Substrate Properties

Five Important Substrate Properties

There are really only 5 important substrate properties. total pore space, water holding capacity, air space, bulk density and particle size distribution Without these proper physical properties nutrients in the compost will not be effective. We all know a good substrate must drain well but not get too dry nor retain too much water. It should be always moist yet not hold too much water. The ideal potting mix should be able to be watered every day so as to bring water, nutrients and air to the plant roots. The water applied every day from the top of the pot drives old air containing carbon dioxide out from the bottom and suck fresh air in from the top. It can do all this via the above stated physical properties. I grew up in Florida. These were my formative years. Somehow I grew an affinity for plants, flowers in particular during this time. So when I came across this very well put together .pdf file from the University of Florida, it caught my eye. Check it out. It is all about substrate particle size properties....

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pH and Organic Substrate Nutrients

pH and Organic Substrate Nutrients

Nearly all of us are familiar with pH as a method to quantify fluids to ascertain if they are acidic or basic. It is common knowledge the scale goes from 1 to 14 with 1 to 6 being acidic, 7 neutral and 8 to 14 basic. The pH shows the concentration of hydrogen ions, H+, within the liquid. So why is the topic of pH so basic whenever we discus live organic soils? The reason is that pH impacts what kinds of microbes live in the soil. Different microbes promote or suppress nitrification along with other organic behavior which impact the way plants develop and grow. Bacteria will increase the pH while fungus lowers it. The soil pH is effected by microbes more than the microbe is affected by the soil. . Preferred pH levels of Different Plants As we all know, every plant has it’s preference for a certain pH level. But ideal pH for any plant, has more to do with its preference for a specific bacteria and/or fungus  than it does with the biochemistry of pH. This is not to say certain nutrient up-takes are not effected by pH. Refer to the chart on the right.(click to enlarge) It outlines which elements are available at what pH. This is standard biochemistry. So there are two points to consider here… plant microbe preference and elemental behavior at specific pH levels. In general, woody forest plants such as trees and bushes have fungal symbiosis. Fungus thrives in low, acidic pH. So you will find acidic soils in the forests. In contrast, soft vegetative plants, such as our precious herbs, have a symbiotic relationship with bacterias. Bacterias thrive in their low, basic pH environ. So would you say herbs prefer a low pH or would it be more descriptive to say veggies grow better in a highly bacterial soil? . Hydrogen is a Cation The hydrogen cation is used as an exchange currency for other cations in the exchange. When you have a great deal of hydrogen ions, the pH is minimal and the liquid is said to be acidic. In a similar fashion, when you have few hydrogen ions in the liquid, it is said to have a high pH, which is alkaline or basic. I have always wondered why a pH is LOW when it has HIGH amounts of Hydrogen. This is because when calculating the pH mathematically, a negative logarithm is used. (see formula below) We are herb growers and therefore really don’t need to be experts and learn that much more about pH. However we do need to know that each time an herb plant’s root tip interchanges a H+ cation for a nutrient cation, the amount of hydrogen ions within the liquid will increase. Because the concentration of H+ cations increases, the pH decreases, which makes the substrate progressively more acidic as nutrient up-take increases. But the pH many times,  balances out since roots (click on image right) also take up negatively charged anions. Just as plant roots use H+ as an exchange currency for cation exchanges, they use hydroxy, OH- for an anion exchange currency. More OH-, in your solution increases the pH since it reduces the percentage of H+ cations. Amazingly, fungi and bacteria are little enough to receive and shed cations and anions on their surface area, electrolytically retaining or expelling mineral nutrients from decomposition in the soil. This, also, has an influence on the pH. So with so many variables effecting the balance, being aware of the substrate’s pH is helpful in choosing what you need to add to the...

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Original Bocashi Recipe

Original Bocashi Recipe

Bokashi in  Japan The word, “bokash”, in Japanese  means “obscuring the direct effectiveness”. In 1961, Japan enacted the “Fundamental Law of Agriculture” in hopes of increasing the poor rural farmers economic horizon. Soon afterwards the Japanese government began to teach these same poor farmers how to grow organically with inexpensive fermenting and composting techniques. By the early 1970’s  the farmers (on their own initiative) invented a fast method to decompose their organic feed stocks and at the same time have a slower nutrient release. . Bocashi in the West The  word “bokashi” has been slightly modified in the West to “bocashi”. The word “bocashi” comes up in conversations, recipes and literature concerning composting, quite often. I have noticed that the word is used loosely to signify some sort of Japanese compost making recipe. But there is really no knowledge of how it originated, it’s reasons why nor how. The bocashi making recipes normally refer to a compost to be used as fertilizer or  as an anaerobic, home, kitchen system which neatly composts your meals leftovers under the sink.  No method is right nor wrong. I take my hats off to the Japanese ancestors for working with composts a whole lot longer than us internet, newbies to organics. Recently I was taking classes at INA (Instituto Nacional de Aprendizaje) in Cartago, Costa Rica to see what variations they know concerning composting, microorganisms, bio-fermentation and organics in general. I found their longer standing faculty very knowledgable, energized and enthusiastic about teaching organics. During a field exersize one of the professors, Ing. Saolo Compos, mentioned Bocashi. I immediately jumped on the opportunity to get his tale on exactly what he was referring to when using the word. Here is what he said: . Original Bocashi Recipe in Costa Rica Bocashi making here in Costa Rica uses a special recipe introduced from Japan. The Japanese came here to Cost Rica some 20 years ago and gave microorganism use instructions to a few interested groups including Coopebrisa in the Zarsero area. To this day they thefarmers in Zarcero are still practicing what was taught them so long ago. In any case my understanding of the original bocashi recipe is the following: Bocashi Components 1 part- Semolina, rice bran or a component similar with plenty of carbohydrates for microorganism energy 1 part- Powdered charcoal, or what is called Biochar these days 2 parts- chicken or cow manure 2 parts- rice hulls 6 parts- virgin soil 60% humidity- Plenty of water with a 30% raw sugar content such as molasses. 1 part- Microorganisms (EM or MM) Bocashi Protocol In making bocashi, the general idea is to have all the components mixed evenly fro even fermentation. This is usually accomplished placing the rice hulls on the bottom first, then making consecutive layers of the other components, mixing them well at the end. The entire mix should containing a 60% moisture level. This level is usually understood to mean wetting the components as the layers are laid until they are evenly moistened similar to a sponge that is wrong out. The moisture lets the microbes move about and gives them a place to deposit their metabolites. The MM or EM microorganisms are prepared before hand and normally placed in a backpack pump and sprayed evenly over each layer as it is laid down. The pile is covered with plastic and let to ferment. The temperature rises to 70C within as little as 24 hours. The pile is turned every day so as to keep the components degrading aerobically. Within 8 days the bocashi should be close to stabilizing...

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Compost Determinant Factors

Compost Determinant Factors

Particle Size Temperature Humidity pH C/N ratio Aeration Microbe growth There are a number of factors that need to be adjusted for the optimum quality and production time. Missing any one of of the above determinant composting factors will limit the effectiveness of the natural process taking place. Compost Component Particle Sizes All particles sizes need to be as small as possible. In a lengthy, natural process in the forest the particles are all shredded by larger macro-organisms like arthropods. But these larger insects we want to keep out of our pots… besides it takes months for them to shred plant materials. A small particle size gives easy access to the bacterias and fungus for molecular bond division. These two microorganisms will be breaking down the material by depositing digestive enzymes on the surface of the components. Bacteria and fungus do not have mouths. The material will need to be pre-digested for the microbes to absorb them into their tiny bodies. The materials we use for our high nitrogen compost at Organic Soil Technology comes to us inherently small particle sizes except for our sugar cane stalks.  The cane is already smashed and broken for microbe easy access but a last shredding is done. Our other components of rice hulls, manures and rice meal are already shredded giving them a large enough surface area for microbe access. Small particle sizes create more surface area. Surface area is an important component when we are talking organic technology. Surface area influences not only compost temperatures and rates, surface areas influence pot-substrate water retention and cation exchange capacity’s for nutrients. . Temperature Open air composting is an aerobic exthermo-biological reaction where temperature moisture and air all effect each other. Therefore proper temperature is important as heat is released in the procedure. You will find different recommended temp targets depending on which University’s information you are studying. But here at OST we maintain a higher temp than most recomendadtions. In our view high temperatures of between 65C and 75C should be maintained during the thermophilic stage. The major reason for high temperatures is to rid the materials of pathogens, live seeds and macro-organisms. The reason for keeping the compost below this range is because at higher temperatures there is a loss of nitrogen in the form of ammonia from vaporization when the C:N ratio is low. The C:N ratio also effects the temp. Too much carbon and your target temp might never be reached. So a drop in temperature when the compost is still young means the pile is becoming anaerobic. Anaerobic decomposition is a much cooler process. The pile will need aeration when the temp drops to get air to the aerobic microorganisms at work. As you can see monitoring the temperature during the process can tell you a lot. The temp should reach 70C within 2 to 3 days. Monitoring the temp throughout the composting will give you a good idea just where the composting process is. There will be different temps in the pile due to surface area loss and aeration. So go deep into the pile for readings. Sanitation | Lethal Compost Temp Specs Sanitation of the compost will take effect for different microbes at different temps and temp durations. Viruses 1-2 hrs at 55 to 70C Non-spore-forming bacteria 5 to 30 min at 50 to 60C Spore forming bacteria 5 to 10 min at 121C Fungus 1 to 2 hrs at 55c .  Humidity We need to keep the humidity percentage at about 60%. An anaerobic process will take over if the humidity is higher. Microorganisms use water...

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Compost Components

Compost Components

There are 4 major categories of component for Organic Soil Technology’s compost. These would be the same categories of materials that you would need as well if you would want to mount your own composting. Fibrous plant material with plenty of carbon Feedstock high in nitrogen or protein Sugar/carbohydrate source for microbe energy Biochar The above components have much to do with the C/N Ratio. To understand why the below components are necessary, check out the Carbon Nitrogen Ratio Post   Fibrous Carbon Source Animal Litter- Many components, materials or feed stocks used for a protein/nitrogen source could also contain carbon as well. So we wont try to place all types of materials in only one category. For instance animal litter, such as coming from poultry, would not only be high in nitrogen but fiber as well. At Organic Soil Technology we incorporate the bedding from chicken houses as well as pure droppings. Poultry droppings has always been recognized as an important component (D.R. Sloan, G. Kidder and R.D. Jacobs) in a variety of organic fertilizers. Fresh litter bedding in many countries, is pure rice hulls. After a few days it contains too much manure for the poultry and is changed. This poultry litter can be used for composting with a 10 to 20% nitrogen content and 80% fibrous hulls. Sugar Cane Stalks– For good or bad, right or wrong Costa Rica produces a lot of sugar. It is not grown organically and as we all know sugar cane plantations have a bad name ecologically. But for our organic compost we take advantage of their fibrous byproduct from the cane stalk that would normally be trashed. This is perhaps the best carbon source obtainable anywhere. After most of the sugars have been squeezed out of the cane in it’s processing, what is left is a superior composting material easily broken down by microbes like the Bacteria Actinomycetes. It serves as a carbon source along with added rice hulls. The wasted sugar cane stalks are ideal for composting because not only is much of the carbon in the cane available for microbe decomposition, it also has sugar residues embedded throughout its structural matrix. The sugars help to energize (feed) the bacterias and fungus while they are busy breaking down the other materials in the compost. Rice Hulls- The rice hulls actually have very little “available ” carbon since it is mostly composed of cellulose and lignin, too hard to break organic molecules that resist the decomposition process of most microbes. But some carbon is available and rice hulls add to the needed air flow in the compost pile and latter in the substrate. using rice hulls without first integrating them threw a 70C composting is not recommended. During the composting cycle the high temperatures render the few rice hulls that still are viable seeds, sterile and empty. . Nitrogen and/or Protein Source Why do we say “Nitrogen AND/OR Protein” source? Because either one will give us a usable nitrogen called Nitrate, which is one of the most important nutrients a plant requires for fast growth. Nitrogen is used by the plants to produce proteins for all cellular functions. So proteins contain a lot of nitrogen. Proteins can be easily broken down by microbes after the death of the plant as part of the nitrogen cycle into ammonia, NH3+. With the hard work of nitrosomonas bacteria it is converted into Nitrite, NO4-. At this point a group of bacterias called nitrobacter break it down to the final Nitrate the plants can actually absorb. So any source of Poultry Droppings– The droppings...

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Advantages of Composting

Advantages of Composting

Boy… lots of advantages to composting compared to the natural process of a fallen leaf that will eventually be recycled by mother nature. There are also advantages over chemically synthesized fertilizers. This is what technology is all about, whether we are going to Mars or the garden, composting is a very good example of how technology… organic technology is an improvement over what we have been handed by nature and what we have done in the past. The concentration of nutrients are higher in a composted material. The composted material, by reaching 70C (150F) is free of pathogens. There are no thermophilic microbes in the soils to break down the hard to restructure cellulose and lignin in cell walls. Lignin is a hard to break carbon chain comprising 25% of all cell walls. It is the hard brown material you see in tree barks and woody materials. (Microsoft word spell check can not be trusted with the word “lignin”. It will change it to “linguini”. So take care.) Compost renders the raw materials in 30 days compared to up to 200 days in a natural process. Composting makes use of more raw materials than what nature is given to use. Composting is less expensive than buying fertilizers. Composted fertilizers are beneficial to the environment compared to synthesized chemical fertilizers that leach and then contaminate the water-tables and rivers....

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Best Organic Compost Basics

Best Organic Compost Basics

Making the decision to use a live organic soil medium for your herbs and veggie plants is the best choice. It shows you are up to date on a rapidly developing earth progression as well as being cognoscente of advanced technology for herbal nutrition and taste. So since you are at the top of your class, try and remember all the details, even the ones that are not necessary in compost construction. The small unknown details are actually really fascinating. Making the best organic compost is a nobal endeavor. Live Organics is Microbes and Substrates Live organics means microbes and substrates. The substrates will most likely be chosen with built in nutrition.  Unlike traditional hydroponic systems, live organics is all about nutrition buffers (small batteries full of plant goodies) created by microbes and kept available via humus cation capacities. The substrate’s built in nutrition buffering humus is based on a compost. The best organic compost can be made by anyone with the time, interest and ambition to do so. But get ready… if you don’t have the time and knowledge to get it right, you might be better off letting a professional do it. Besides the practice and knowledge, you will be needing a few cultures of different beneficial microorganism (BM’s) groups and feed stock. You can do it without special microbe inoculation but to make the best compost it would be good to also know how to keep around some cultures of specially talented bacterias like lactobacillus and actinomycetes. A good collection of some beneficial fungus like trichoderma and levaduras are important as well. Three Phases of a Compost mesophilic phase (temps lower than 45C, with Bacillus mesophilos & Bacillus subtilis)) thermophilic phase (temps btw. 45-70C with Actinomyces thermophilus, Bacillus thermophilus & levaduras ) maturation phase Microbes in The 3 Phases of Composting Mesophilic Stage The cooler mesophilic stage of composting takes place below 40C. Mesophilic bacteria predominate at this stage however fungus will be found in all three stages of composting.  Bacterias are the most abundent microbe found in composting in general. They make up roughly 70% of the microbe compost population. They are the most divers microbe exuding more types of enzymes for molecular bond breaking than fungi. Most of the heat in a compost pile is from bacterial metobolic activity. Thermophilic Stage When the compost temp exceeds 40°C, thermophilic bacteria take over, mostly from the genus Bacillus. The different species of bacilli is very diverse at temperatures around 50°C and decreases at 60°C and higher. When temperatures become too high or low, bacilli form endospores  which are very resistant to extreme temperatures as well as a lack of moisture and food. When conditions permit, the spores open and the bacterias become alive and active once again. At temperatures at and above 70C, the genus of bacteria called Thermus take over. Cow droppings contain Thermus. Thermus can be found in hot springs and any other place a 70C and above temperature is naturally created in nature. Fungus in the thermophilic stage will be found in the cooler outer layers of the pile. Maturation Phase The maturation phase contains the 2nd phase of mesophilic decomposition as well as a much slower process when temps go below 40C. So look for all the mesophilic bacterias and fungus in this stage as well as actinomycetes bacteria. Actinomycetes are much like a fungus, but like all bacteria do not contain a nuclei. They have long filaments like fungi hyphea which will divide into spores when the conditions are ripe. They are very adapt at breaking down some organic compounds like chitin,...

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Carbon Nitrogen Ratio

Carbon Nitrogen Ratio

Anyone that has been exposed to a learning process relative to composting, has surely heard of the Carbon Nitrogen Ratio, C:N. So without more details than is needed, here are the principals behind the C:N ratio concept: Carbon Nitrogen Ratio | Composts Microorganisms are behind decompositions of organic matter that creates our nutrient packed compost. These little guys need a certain ratio of carbon and nitrogen to satisfy their metabolic processes. Carbon found in carbohydrates and or sugars are metabolized to produce energy for the microbes work. The nitrogen is used to create proteins for building cell structure. The C:N ratio refers to the relative proportions on C and N. A ratio of 25 to 30 parts carbon to 1 part nitrogen is what we are looking for to make the process optimum for a compost used for fertilizing plants such as herbs and vegetables.  This is a 30:1 ratio or more simple stated, a C:N of 30. If the ratio is far from this mark the decomposition slows as more complex metabolic processes are needed to continue decomposition and a growth curve for the microbe. For example if there is excess carbon in the compost due to a lack of nitrogen , when the compost is use for gardening , microbes will kick in and rob the surrounding substrate, soil or fertilizer of nitrogen that was meant for the plant. If there is not enough carbon in the compost mix, excess nitrogen ends up as ammonia that can not be used to complete the Nitrogen Cycle, and evaporates into the atmosphere. What a wast of nitrogen that would be. The University of California did an intensive study not to long ago with C:N ratios from 20 to 78 and found that a ratio of 30 to 35 was optimum. They also found that even though the optimum for compost is a C:N ratio of 30, a variance will not effect the quality of the compost significantly. The California research showed that a composting of feedstock material with a greater C:N ratio would not be that harmful to the soil. The extra  C is so slowly available that nitrogen robbery is minimal. Carbon Nitrogen Ratio | Soils The optimum ratio in soil or substrate organic matter is different than when you are beginning to creating a compost mix with raw matterials. A 10 carbons to 1 nitrogen ratio, or a C:N ratio of 10:1 is optimal. Following are some sample C:N ratios of organic matter: Sandy loam (fine) 7:1 Humus 10:1 Food scraps 15:1 Alfalfa hay 18:1 Grass clippings 19:1 Rotted manure 20:1 Sandy loam (coarse) 25:1 Vegetable trimmings 25:1 Oak leaves 26:1 Leaves, varies from 35:1 to 85:1 Peat moss 58:1 Corn stalks 60:1 Straw 80:1 Pine needles 60:1 to 110:1 Farm manure 90:1 Alder sawdust 134:1 Sawdust weathered 3 years 142:1 Newspaper 170:1 Douglas fir bark 491:1 Sawdust weathered 2 months...

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Chelation and Live Organic Soils

Chelation and Live Organic Soils

The word chelate translated from the Greek word “chel”, means crab’s claw. It refers to the claw like manner in which a metal (usually iron) is loosely bound in a chelated molecule. Elements are more easily absorbed by plant roots in chelated form than elements that are not chelated. Chelates are organic molecules that can retain or release specific metal ions. These ions would include plant nutrients such as calcium, magnesium, cobalt, copper, zinc, iron and manganese. A chelate is a molecular compound forming a complex of cations with organic compounds forming a ring structure. Upon entering plant cells cationic nutrients will form chelates with organic and amino acids. Chelation enables the nutrients to move freely inside the plants. The chelation process increases the mobility and therefor availability of nutrients to plants. . Chelates And Cation Exchange Capacity Chelate’s end effect is much like a cation exchange in the sence that they hold elements until they are needed and then releases them for plant use, but the chemistry for doing this is different. Chelates work outside and inside of the plant. Outside the plant cell, in the soil, a chelated element is kept in reserve and can not form a compound with another element and participate out of the water medium. Once inside a plant cell some metals are prohibited from moving freely. But when they are in chelated form the needed metal is able to move readily inside the cell and from cell to cell. Chelation, Chlorophyll and Blood Chelation takes place not just in the soils and plants. It is an ongoing fundamental process in plants and animals. Us humans are dependent on the continual process of chelation as well… in our blood for example. You and I are more related to our herb plants than we think. Both of us rely on a chelating compound, fundamental to our structure. Within humans, it’s the deeply crimson heme which transports, via our blood, the much needed oxygen cycled by vegetation. Plants as well have a vital chelation substance, green chlorophyll. It is so related to heme that you only have to exchange an iron atom for a magnesium atom, to have the identical molecular structure. Examples of Chelated Elements Chelates are constructed from the complexing of cations with organic compounds resulting in a ring structure. If you click on the examples below you can see the central M (metal) in the chelate “claw”. The metal will will not participate out of solution and once inside the cell, will be released when needed. . Positive Aspects of the Chelation Process: 1. Increase in available nutrients. Chelating agents will bind insoluble iron in alkaline soils and substrates to make them available to plants. 2. Prevents nutrients from forming insoluble, unavailable compounds. Chelating agents of metal ions will protect the chelated ions from unwanted chemical reactions and therefor increase the availability of those ions for plant uptake. 3. Chelates reduce toxicity of some metal ions to plants. Chelation in substrates reduces the concentration of metal ions to a normal beneficial level. The process is done via humic acid and high molecular weight compounds found in organic matter. 4. Chelates prevent nutrients from wash out. Metal ions which form chelates are much more stable than free ions. 5. The chelation process increases the mobility and therefor availability of nutrients to plants. 6. Chelating agents reduces the growth of plant pathogens by reducing available iron....

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Colloids in Substrates | Clays vs Humus

Colloids in Substrates | Clays vs Humus

Soil colloids are the most dynamic part of all soils and substrates. It establishes their chemical and physical attributes. Two of the most important colloids in soils are clay and humus. However,  substrates for potting mixes humus  is king. So Heads Up! This is very important. In typical soil it is the inorganic colloids, mostly clays, that are the most abundant components. However, in a well made substrates for potting mixes it is the tiny organic humus, less than 0.001 mm across that will determine the availability of nutrients for the plant. Organic humus colloids are many times more active than inorganic clays because of their higher CEC. It is fairly easy to add enough humus in potting soil where as field soils are too extensive. For a good potting soil, what needs to be done is pack the substrate with the optimal quantity of humus. Younger plants need less nutrition. Too many colloids charged with nutrients will burn it. . Characteristics of a Colloid Humus is amorphous, meaning their physical and chemical characteristics are not very well defined. Clay particles are normally crystalline, making clay’s physical and chemical characteristics anamorphic. Both inorganic and organic colloids are  components of most soils and substrates. (When I speak of “soil” I am referring to soils in fields. When I us the term “substrate”, I am referring to potting mixes.) The majority of the substrate solids like coco fiber and peat moss, are inert leaving the organic humus to define the substrate’s physical and chemical properties. So, when looking for a well made, effective substrate, look toward the quantity and quality of the humus ingredients. The passive biochar humus and the active humus in the compost are chief concerns. Since organic humus does the same job as clay but better, don’t look for clay in a substrate. .   The most essential quality of a colloids is its capacity to adsorb, keep for a time, then discharge ions on its surface. Most colloids have an overall negative charge due to their chemical and physical make up. That negative charge will be balanced out through a large number of cations attracted to its outer surface. Therefore, colloids could be seen as large anions covered with a group of rather loosely stored cations. Typical water molecules can also be adsorbed onto colloid surfaces. They will be found in the hydrated arrangement on the cations. The volume of water around a specific cation is very important, since the effective radius of the cation goes up with more H2O or down with less. . The Size of Colloids Colloid’s characteristic of being very small, is important to the cation exchange. For example, take a clay particle, known for its high cation exchange capacity. The individual clay particles are so tiny, you can not distinguish one from the other under a microscope. These small particles, when mixed in water, do not dissolve but are suspended indefinitely. They do not settle as sediment at the bottom of the container nor are in solution. A substance with this suspension characteristic is called a colloid. As mentioned, the size of the particle is very important. If a substance is small enough, when there is a positive or negative charge close to them they are effected… attracted or repulsed. This would not happen to a larger particle because if its greater mass. All small partials are effected by electrostatic charges, even bacteria and fungus. Humus is a colloid, which, like all colloids, does not float to the top nor settle out to the bottom. Colloids because of their miniscule size have...

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Cation Exchange Capacity of Humus

Cation Exchange Capacity of Humus

The cation exchange capacity (CEC) of the soil is merely a way of measuring the amount of sites in soils or soil humus that have a negative charge. These hold on to positively charged particles (cations) by means of its electrostatic properties. The amount of such exchange sites measures the capacity in the soil to keep nutrients, or the cation exchange capacity (CEC). So a soil’s CEC is the sum of negatively charged nutrient exchange sites  per unit weight or volume. CEC is calculated in milligram equivalents per 100 grams (meq/100g). Adding the concentrations of each cation gives a figure of the overall  CEC. A figure above 10 (meq/100g) is preferred for normal plant growth . However substrates with high levels of humus can have a CEC of 30 (meq/100g) or more. The 5 most important cations in soils are calcium (Ca++ ), magnesium (Mg++), potassium (K+), sodium (Na+) and aluminium (Al+++). . Cations and Anions What we really need to understand is that the greater the CEC value, the more nourishment a substrate or soil can have ready for use. The higher the CEC value, the more effective it can be for improving plant growth, vigor and health. All very small particles, not just humus and clay, carry electrical charges. The part of the nutrient that carries the electrical charge are called ions. Ions with a positive charge are called cations and ions carrying a negatively charged are called anions. . Humus and Available Nutrients Depending on the soil or substrate, there are a few ingredients that have cation exchange capacity. The element having the highest CEC would be humus. Organic substrates all contain a good amount of this organic compound. Cations held by the electrostatic force of the soil’s humus can be easily exchanged for other cations within the soil making them readily available for plant uptake in the rhizosphere. Therefore, the CEC is crucial for knowing if there are sufficient amounts of AVAILABLE nutrients in the soil that have a positive charge. . Common Nutrient Cations And Anions Some important positively charged nutrients include,  Ca++, Mg++ and K+. You may note that a very important nutrient, Nitrate NO3-, is not listed. This is because it carries a negative charge. Humus has not only negatively charged ions ready for retaining positively charged minerals, some have positively charged ions as well which can hold on to negatively charged minerals such as our precious nitrates and nitrites. However the anion exchange is very low in relation to cation exchange sites and unfortunately doesn’t come into account when talking nitrate availability. Examples of Cations: NH4+, Ca++, Mg++, K+ Examples of Anions: NO3-,  Cl-, SO4-, PO4- . How Plants Eat The surface areas of a plant root hairs contain their own electrical charges. Any time a plant’s root hair penetrates the substrate, it may exchange its own cations for those mounted on humus or clay debris and then absorb the cation nutrient for intake as nourishment. Plant roots use a hydrogen cation (H+) for the exchange. They eject one hydrogen cation for every cation nutrient adsorbed. This keeps a charge balance. This is the way plant life eats. This is a basic function of all plant life. . If there is a larger concentration of one specific cation over the others in the soil water, that cation will force the other cations off the colloid and the abundant cation element take their place. . Absorbsion vs Adsorbsion Positively charged particles are electrostatically attracted to negatively charged particles. We all know this intuitively from our times spent playing with magnets as a...

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Humus | What It Is

Humus | What It Is

All organic matter, as it decomposes, forms smaller and smaller particles. When it breaks down as far as it can and yet still can be identified as organic matter, it is called humus. The process of “humification” takes place naturally in soil and substrates, or in the production of special compost, like the bakashi. While plants die-off and are broken down into simpler compounds by microbial fungi and bacteria they’re eventually transformed into humus. All humus is a carbon based, organic substance. It is made of extended, tough chains of carbon compounds with a sizable surface area. The surface areas hold electrical charges, that draw in and store nutrient particles called cations. Humates are notable for their humic acids, namely Humic, Fulvic, and Ulmic. Humus is known as a colloidal substance, and boosts the soil or substrates cation exchange capacity, CEC. Humus is the “life-force” of living organic potting soil. Humus | Decomposing Matter The difference between humus and compost is that decomposing compost matter is an inhomogeneous substance, with rough plant parts observable. An entirely humified organic substance, on the other hand, will be consistent in character, with specific shape and structure. Humus is the ultimate stage in the decomposition of organic matter. Humified organic matter, observed through an electron microscope, will show very small yet plainly recognizable plant remnants which can only be mechanically broken down once the decomposition has been completed. The image on the right is an electron microscope rendition of humus/brown, decaying compost/green, and mineral particles/purple.  Scientist and researchers have a very specific definition of humus but not so in our horticultural community. . Active and Passive Humus Rich compost, ready to apply is generally known as active humus. It is applied as a top dressing or as a substrate component with organic compounds that will release more nutrients when they are decomposed further. But in scientific circles, if the organic compound is not totally decomposed, it is not humus at all. Researchers define humus as a stable, passive molecule  which would not change structures in the soil unless it is a simple mechanical breakage into two or more pieces. But for horticulturalist, humus comes in active and passive forms. Active humus in compost is still abundant in plant remains unbroken into it’s simpler stable form. Passive humus composed of humic acids and humins, will be so very insoluble they can’t be divided further by microorganisms. Therefore passive humus is considerably immune to additional decomposition and provides very few readily accessible nutrition to soils and/or substrates themselves. . Benefits of Humus There are many benefits to plants which humus provides. Humus can hold up to 90% of its mass in water, and so enhances the soil’s ability to store water. The chemical composition of humus allows it to buffer abnormally high or low levels of pH in the soil. Harmful elements including heavy metals and even too much nutrients, will be chelated, which means bound to the organic compounds of humus and kept from moving into the system. Also, during the humification, fungi and bacteria always exude sticky gums that promote a beneficial assembly of the potting soil by maintaining particles together. This allows even better oxygenation of the soil substrate. Particle distribution size is a very important physical determinant to soil drainage and oxygen supply. Larger particles allow for more air and less saturation of water. The biggest benefit of humus however is its colloidal characteristics. Humus is THE number one ingredient that will maintain nutrients (cations) in substrates so they will not wash away when watered. At the same time the collation...

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Live Organic Potting Mixes

Live Organic Potting Mixes

The 4 Main Physical Properties of Potting Mix Components As defined by Oregon State University- James Altland, Ph.D. a stability for root anchorage, a reservoir for nutrients, provide for an oxygen and gas exchanges for the roots, provide a space for root water up-take How materials function together on a  mechanical level If you use the identical potting soil mix in a small container as a larger container, the perched water table remains the same. See the example figure below. This is why OST has different mixes for a small pot for cuttings, a different mix for a 1 gallon pot for growth and yet a different mix for for a 5 gallon pot for the flowering stage. . Formulating a Potting Mix For Every Purpose “It is possible to formulate a growth medium for a specific container size, growth environment, management intensity and the plant’s requirements. It has been noted that container depth directly affects the percent of the growth medium that is filled with air at container capacity. A growth medium for plants grown in a greenhouse, where control of the moisture level is possible, can have a greater water-holding capacity than a medium for plants exposed to natural rainfall distribution. University of Florida Extension Service Root Anchorage Nutrient Reservoir Gas Exchange H2O Space A good media needs a combination of larger particles that bind the entire potting mix together to hold the plant in place. OST’s root anchorage is affected by peat moss, coco fiber, Macadamia shell Biochar and residual palm leaf fibers which are added before composting. When using BioChar in combination with the a 8 ingredient Organic Compost, you have a nutrient reservoir unlike most. BioChar is layered and porous providing a large surface area for cation exchange. The positively charged anions attract the negatively charged cations of the nutrients. This is especially effective with nitrate. Container medias must have sufficient pore spaces to allow free movement of gases.  Plant roots constantly undergo respiration.  Respiration is a cellular process that burns sugars to create energy (sugars are generated by photosynthesis in leaves).  Cellular respiration consumes oxygen and releases carbon dioxide (CO2) as a byproduct.  There must be sufficient pore spaces in the media for plant roots to acquire oxygen and expel CO2.  This tradeoff between CO2 and O2, called gas exchange, is an often-overlooked aspect of selecting container media.  After containers are completely saturated and allowed to drain, 10 to 30% of the container volume should be air space for gas exchange. Container media has to retain water for plant roots.  All medias retain water, some more than others.  For example, peat retains a great deal of water while sand retains very little.  Peat moss and coco fiber can be purchased in a wide spectrum of particle sizes, with smaller particles holding more water than large particles.  After containers are saturated and drained, 45 to 65% of the container should be filled with water. Of water held by container media, some is available to plants and some is not.  Through physical processes called adhesion and cohesion, water is bound to media to form a thin film over particle surfaces.  This thin film of water is generally unavailable to plant roots.  Available water content is the portion of the water in a container accessible to plant roots.   The 4 Main Nutritional Properties of Organic Mix Components The quantity of available major and minor elements The quality of the microorganism community The ability to retain and store the elements The ability to release elements when needed   The material list you see in our organic...

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