Humic Acid is the commercial term often used to refer to the combined humic and fulvic acid content found in naturally occurring decomposed plant and animal residues. The most bio-chemically active humic acid is derived from Leonardite coal, which consists of humified animal and plant substances dating back thousands of years.
Humic acid is effective at improving the quality of all types of soils, especially clay and sandy soils and organically deficient soils. The introduction of humic acid to clay or other compacted soils, results in the break-up of these soils allowing for greater water and root penetration. In sandy soils, humic acid adds vital organic material back into the soil, which allows for improved water retention and deeper root development, both of which are lacking on sandy soils.