What is the Difference Between Humic Acid and Fulvic Acid?

Humic acid and fulvic acid are both humic substances that play essential roles in soil and plant health. They differ in various aspects, such as molecular size, structure, acidity, and functionality. Here are the key differences between humic acid and fulvic acid:

1. Size and structure: Humic acids are larger molecules, while fulvic acids are smaller molecules. Humic acids can form small solid pieces when extracted, while fulvic acids remain dissolved under the same conditions.
2. Molecular weight: The molecular weight of humic acid is heavier than fulvic acid, resulting in higher water retention capacity.
3. Acidity and oxygen content: Fulvic acids are more acidic and have almost double the oxygen content of humic acids.
4. Function in soil and plants: Humic acids improve soil structure, stimulate root and shoot growth, and enhance microbial activity in the soil. Fulvic acids, due to their smaller size, can be easily absorbed by plant roots, stems, and leaves, carrying trace minerals and other nutrients with them. They are also more effective at chelating nutrients for plant uptake.
5. Solubility: Fulvic acids are soluble in water at all pH levels, while humic acids are only soluble in high pH conditions.

Both humic and fulvic acids are essential for healthy plants, and using one without the other may not provide the full benefits to the plants. They work synergistically to boost plant growth, with humic acid improving soil health and fulvic acid aiding in nutrient uptake. Therefore, it is recommended to use both humic and fulvic acids for optimal plant health.

Comparative Table: Humic Acid vs Fulvic Acid

Here is a table comparing the differences between humic acid and fulvic acid:

Both humic and fulvic acids are humic substances, but they differ in their solubility, plant absorption, molecular size, acidity, degree of polymerization, molecular weight, and color. These differences impact their benefits and how they are best applied in plant nutrition and soil improvement.