Humic Acid FUNdamentals

  • Thread starter jigglybones
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Humic acids are a source of concentrated organic matter derived from various sources. Plant materials go through several stages of decay: fresh plant material, green manure, compost, peat, brown coal, leonardite and coal. These materials accumulate over time, and with heat and pressure they eventually form bands or layers in the soil each with a different composition of humic acids.

Humic acid is an umbrella term for humic substances. There are two main categories of humic acids or humic substances: humic acid and fulvic acid. Each group is a mixture of large molecules. Therefore, there is no one recognized chemical structure for humic acid or fulvic acid. The main distinction between humic acids and fulvic acids is their pH and solubility in water.

Structurally, humic acids are large molecules containing an abundance of oxygen and carboxyl groups. These oxygenated areas on the molecule attract and bind with trace minerals in the soil that would otherwise be unavailable to the plant.

Humic substances stimulate the growth of plant tissues and increase the total quantity of nutrients absorbed. The large humic acid molecule binds with minerals in the soil to act as a bus to deliver these minerals to the plant root in a useable form. There are different amounts of oxygenation in each humic acid source. Leonardite has the most heavily oxygenated molecules yielding more nutrient binding sites. Humic acid extracted from manure or peat is usually not as effective in absorbing micronutrients as humic acid originating from leonardite.
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