Iron Earth Canada

What is Fulvic Acid?

Fulvic acid increases the bioavailability of soil minerals by being able to chelate them (i.e., bind to them) and bypass the cell wall of a plant.

In order to understand fulvic acid, we need to revisit our elementary school science curriculum for a quick refresher on soil, that dark and magical substance from whence all life springs.

At a basic level, soil is essentially composed of various combinations or percentages of sand, silt and clay. Intermixed with these mineral particles is a decomposed organic matter called humus. So, what exactly is humus?

What is Humus?

In a natural environment, when plant life dies and returns to the soil, it is extensively digested and decomposed by microbes, bacteria and soil dwelling creatures. The end result of this decomposition is humus, a layer of soil comprised of special (humic) substances that not only give soil its structure and allow it to hold water, but also assist plant roots with mineral uptake.

At first glance, humus may easily be dismissed as the rotted detritus of what was once a vibrant, photosynthesizing lushness, an inevitable and relatively benign state in the life cycle of the natural world. This idea is, at best, completely inaccurate and, at worst, potentially devastating for planetary soil health.

Unbeknownst to most, within that finished compost heap or decaying layer of forest floor is a complex universe that helps maintain the health and life of our entire planet. It is also the home of fulvic acid.

What is Fulvic Acid?

So, residing in the humus, along with other humic substances, is the diminutive molecule of fulvic acid. Because of its small size, fulvic acid increases the bioavailability of soil minerals by being able to chelate them (i.e., bind to them) and bypass the cell wall of a plant. What does this mean exactly?

When you think of fulvic acid, think “fast.” Fast transport. Fast uptake. Fast nutrient absorption. In order for a plant to survive, it needs to take minerals from the soil. Fulvic acid allows for minerals to be quickly transported from the soil into the plant. Fulvic acid is the express lane porter or the express shipping option – it delivers the goods (i.e., minerals) immediately by binding to them and transporting them into the growing plant.

It is important to remember that, although fulvic acid is an incredible molecule, it will make little difference to plant health if the soil is not rich in minerals or is deficient in humus. When we begin to understand the synergistic complexity of soil health and plant growth, our perspective on the natural world changes… What was once composted sludge becomes a life force; what was once an irritating or phobia-inducing bug, is now an intelligent and integral participant in the health of our ecosystem.

Humic Substances and Fulvic Acid Recap

  • Humus is the decomposed organic matter portion of a soil.
  • The Humus is home to humic substances such as humic and fulvic acid.
  • Humic substances give soil its structure, allow it to hold water and assist plants with nutrient uptake.
  • Fulvic acid, a chelator, increases the bioavailability of minerals in a soil by binding to them and helping them bypass plant cell walls; it is the small and fast transport molecule that assists plants with mineral and nutrient uptake.
  • Although amazing, fulvic acid alone will not increase the health and growth of plant life. Humus, soil minerals and numerous other factors are necessary for optimal growth. Synergy supports life!

Did you find this article helpful?

If so, take a look at this post where we talk more about all the macro and micronutrients in your soil!



Gardiner, D.T., and Miller, R.W. (2004). Soils in our environment, 10th Ed. Pearson Education, Inc., New Jersey.

Nardi, J.B. (2003). The world beneath our feet. Oxford University Press, New York.

Pettit, R.E. (2002). Organic matter, humus, humate, humic acid, fulvic acid and humin: their importance in soil fertility and plant health