With changing climatic conditions comes a greater urgency for more efficient utilisation of nutrients, improvement of soil biology, increases in microbial populations all relevant to Humus in the soil.

Humic Acids

There are many different kinds of Organic Fertilisers on the market, made up of various components, but all in their own individual way able to improve the quality of the soil. The best way to understand why they work is to look at some of the components in their make-up. Those made from manures of animal origin can supply fast and slow release forms of nutrients, particularly nitrogen, as well as bacteria and crude forms of organic matter for the soil. Products containing meat meal, bone meal and fish meal can supply slow release forms of nitrogen, phosphorus and calcium; these materials also help improve bacteria levels in the soil. Seaweed products can supply a host of rare trace elements and nutrients, such as Potassium Alginate and Selenium as well as natural growth hormones. Mineral products made from lime, gypsum, dolomite, kiln dust, rock phosphate, basic slag and felspar can supply calcium, sulphur, phosphorus, potassium and magnesium, whilst a large variety of trace elements can be obtained from rock dusts such as basalt, granite, ironstone and scoria. Humate products made from brown coal, humic acid, or compost from green manure crops, will supply small amounts of nutrients and a broad range of trace elements, but more importantly they supply the very essence of soil structure and fertility - Humic Acids.

Why are Humates so important to the soil?

Humates ,being very dense and sticky, tend to have a sequestering and chelating effect on nutrients in the soil thus preventing them from leaching through the soil profile too quickly, therefore improving the soil fertility. Humic acids also stimulate biological activity in the soil due to their carbon make-up, thus improving the structure of the soil. Humic acids are the fatty acids of the soil, just as fatty acids in the body are important for the production of calories and the absorption of vitamins and minerals by the body, Humates absorb and breakdown minerals in the soil and hold them in an available state for utilisation by the plant when required. The use of slow release forms of nutrients to improve soil fertility allows the plant to feed properly and therefore build a healthy and strong cell structure. For instance, if nitrogen is supplied to the plant beyond its capacity to photosynthesis, this will upset the nutrition of the cell or weaken the cell structure, thus allowing infection to set in.

With the use of Vicmill allSPORTS range of naturally derived Humate based fertilisers and Soil Conditioners problems like the one described very rarely occur.

Many conventional fertilisers bypass the plants normal feeding mechanism of exchanging nutrients for hydrogen ions which the plant is constantly transferring to the soil. Designed and manufactured to dissolve in water, these forms of nutrient are soluble in the soil solution, the plant will thus get an extra boost of nutrient when it takes up water. This solubility in the soil solution also allows nutrient to be lost by leeching into the sub soil before the plant can take them up.

When Vicmill allSPORTS range of Humate fertilisers and Soil Conditioners are applied to the soil, nutrients become suspended in the soil solution. This suspension allows these nutrients to attach themselves to the colloidal clays and humus in the soil so that the plant takes up necessary elements and minerals via its roots. When nutrients reach the plant they have already been broken down or chelated with organic molecules to aide efficiency in the uptake process.

Humates and their "Water Wise" Characteristics

During periods of dry weather humates help stabilise soil temperatures and slow the rate of evaporation due to their insulating properties that help maintain a more uniform soil temperature. This is significant during severe climate changes such as heat waves, because when temperature fluctuations in the soil are reduced moisture is less likely to be released into the atmosphere.

Humates function as water sponges and it is this sponge like characteristic that has the capacity to carry several times its volume in water, even greater than typical heavy clay soils. Available water is without a doubt the most important component of fertile soil and the most critical substance derived by plants from the soil.

Humates and Disease Resistance

Humates decompose and absorb residual salts and heavy metal compounds derived from commonly applied pesticides, herbicides and synthetic fertilisers by binding them to active compounds such as lignin (a complex polymer either positively or negatively charged that suspends these harmful contaminates to the soil molecule) permitting micro-organisms to digest and alter the physical properties of these residual compounds which can then be absorbed by the plant. Plant susceptibility to disease occurs when the leaching of residual salts, heavy metals and organo chlorides surpasses the soils microbe populations ability to break down these harmful residues into plant utilisable forms of nutrients creating a 'constipation' effect conducive to soil borne pathogens and fungi that pass into the plant through the roots into the cellular and skeletal membrane disrupting the plants metabolism and immune defence.

Briefly beneficial microbes, fungi and Pathogens survive and multiply in the biomass of the soil where thatch and black layer issues critically influence the plants roots ability to draw nutrients.

The sustainability of these micro-organisms in the soil will be determined by the interaction of sunlight, temperature, soil moisture retention, nutrient availability and the influence of the soils (pH). Pathogens and fungi may be indigenous or enter the soil indirectly through manure applications or contaminated (sewage) water indirectly influencing the severity of infectious diseases in turf grass such as fairy ring,

Soil Contamination: Why Humates are beneficial

Scientifically any chemical compound that releases electrically charged particles called (ions) when it dissolves in water is a salt. Compound or synthetically derived fertilisers we commonly use in turf actually contain salts which can be detrimental to the plant’s capacity to uptake nutrients via the root system if applied in excess.

Turf grasses are entirely at the mercy of their environment so unfortunately for the immobile plant, when exposed to too much salt it can be a fatal experience.
Once inside the cell, can cause ionic stresses, largely as (Na) Sodium and (Ci) Chloride inhibiting important plant metabolic functions such as protein synthesis (Na) Sodium can rise to toxic levels in mature leaf tissue causing them to die. This reduces the leaf area available for photosynthesis so the plant cannot sustain growth and vigor.

Recognising the signs of salinity can appear as a crusting of salt on the soil’s surface or plants may visually show water stress like symptoms such as wilting or yellowing, followed by a browning at the margins of the leaves, particularly during dry spells as salts dissolved in water become more concentrated, this can become more acute by the best intended fertiliser application, compounding the effects by accelerating water drawn from the plants roots. As the (Na) Sodium content increases there is a tendency to destroy the soils friability and as the plants roots move deeper the effects of (Na) Sodium become compounded in the inert colloidal substructure of soil (subsoil), greatly influencing moisture and nutrient movements slowed by the absence of micro-organisms and oxygen necessary for healthy soil biology.

By increasing the biological health in your soil, Humic substances released by soil borne micro-organisms withhold naturally or synthetically derived contaminates, so while still present, their detrimental characteristics are neutralised and will eventually be broken down.

Why use Organic Fertilisers?

Well then, lets look at history… while using ever increasing amounts of conventional fertilisers and chemicals in agriculture over the last 60 years, the world has lost more species of plants than in the previous 500 years, seen the loss of more and more land each year due to soil erosion and land degradation, had ever increasing crop losses due to insects and according to the United Nations, pesticides are responsible for poisoning some 500,000 people per year. In using natural and organic systems in agriculture, we surely couldn’t do any worse than the current conventional systems.

1. Humus is the main source of fuel and energy for the soil microbial system. Each tonne of manure carries 225kg or more of organic matter – and 70kg or more of net humus. One tonne of compost can support up to 270kg of microorganisms per acre. This can be multiplied by the number of separate life cycles in each season.

2. Humus carries 50% carbon which is used by micro-organisms through fermentation and respiration to convert part of the carbon into higher energy values. Other carbon may also be spent in the oxidation of mineral compounds into simpler and more available forms.

3. Humus as a concentrate of carbon and energy compounds enables bacteria to: a) Survive cold or dry soil conditions or excess water; b) Carry out antibiotic effects in the soil; c) Interrelate with plant roots, important to a cold, wet or delayed seedbed.

4. Humus absorbs the highly active non-nutrient hydrogen to make it acidic, basic to the release and conversion of complex soil minerals as well as varied nitrogen sources.

5. The humus colloid carries three times more absorptive capacity to hold minerals cations, water, air and carbon compounds.

6. The density of humus lies between 0.8 and 0.9 whereas the inorganic clay colloid has a density of 2.65.

7. The humus colloid also buffers microbial and plant systems against excesses of sodium, magnesium, potash and other positively charged minerals.

8. Humus acts to buffer and enhance the four anions: carbon, nitrogen, phosphorous and sulphur in their system of nutritional service to crops. When joined with organic matter and humus they become dynamic nutrients for both soil microbes and plants.

Humic acid

Humic acid is one of the group of humic acids; main constituent of humus and humate materials. Other humic acids are fulvic acid and ulmic acid. (See glossary).

Characteristics of Humic Acid:

1. Stimulation of plant growth by improving transpiration in plant tissues;

2. Humic acid has the power to receive, hold and release essential mineral nutrients in greater capacity than do clay particles (soil colloid);

3. Humic acid is potent chelating agent protecting plant mineral nutrients from adverse chemical reactions (nutrient tie-ups);

4. Humic acid protects plants from excess salts; improves soil fertility by buffering excess salts and making salt minerals available for plant uptake.

5. Humic acid helps plants to assimilate and use phosphates. Plants have a natural difficulty in gleaning essential phosphate from either organic or inorganic forms. The lack of soil phosphates is probably agriculture’s biggest problem.


Enzymes are proteins and are specifically related to individual trace elements such as manganese, iron, copper, zinc, boron etc., without which they cannot operate. In turn these enzymes trigger plant hormones (gibberellins, cytokinins and auxins being the three classes of growth hormones in plants) allowing natural plant growth functions to take place. Plant hormones are responsible for carrying out the following functions:

a) Cell division;
b) Bud formation;
c) Regeneration of roots;
d) Increased seed germination;
e) Induce flowering;
f) Improved protein synthesis.

The role of Humus in the soils

When we put any kind of organic matter into soil such as stable manure, straw, corn stalks, corn cobs, green manuring crops, leaves, weeds etc., a vast army of many species of micro-organisms (bacteria, fungi, worms, etc.) becomes activated and mobilized to convert such inert organic matter substances to an end product called HUMUS. What is Humus? It is a mysterious and still not fully understood negatively charged colloidal complex material remaining in soil as the end product of various biochemical processes. Actually it is the final residual component of organic matter derived from plant materials that has undergone decomposition to the extent that it has lost its identity with its origins. Basic Requirements: To convert organic matter to humus it is essential that several basic conditions prevail in the soil as follows: 1. There must be oxygen for oxidizing various groups of complicated organic matter complexes. 2. At least 2% nitrogen in the form of ammonia or nitrate nitrogen must be available to supply the nucleoproteids for the living cells of the microflora that convert the organic matter into humus. It is of interest to note that humus contains the same amount of nitrogen that we find in the protein molecule, not less than 5.25 to 6.25% nitrogen. Without nitrogen humus cannot be made. A satisfactory level of humus is, therefore, a very important constituent of a good, living and productive soil.

Microbial conversion

Plants cannot feed on inorganic molecules, they use only charged ions or their radicals. The refinement of such essential plant food materials into forms that plants can utilize is accomplished by a large variety of specialized soil micro-organisms that must convert nitrogen to nitrate, phosphorous to phosphate, sulphur to sulphate, boron to borate, molybdenum to molybdate etc. These micro-organisms depend upon organic matter for their subsistence and activity. The plants also help the soil micro-organisms in supplying from their root systems usable compounds in solution such as sugars, and many protective factors such as antibiotic compounds. Plants produce abundant amounts of enzymes, growth hormones and vitamins for the benefit of the humusproducing micro-organisms that help prepare the food for the plants. When winter sets in and all plants have either disappeared or are dormant, the humus in the soil becomes the protector and “living place” for the then dormant micro-organisms. If all goes well then by next spring the cycle will start again. Only in soils with a normal humus content can plants gain enough resistance to counteract diseases and parasitic enemies – insects, nematodes etc.