[Modified Soil] (3) Why is humic acid activated?

Currently, humic acid fertilizers are gaining increasing popularity. A common saying has emerged in the market: “If you don’t mention humic acid when selling fertilizer, you won’t fetch a good price.”

This situation is the result of the efforts of numerous companies engaged in the research, development, and production of humic acid fertilizers. But do you truly understand what active humic acid fertilizer is?

Following “Revamping the Land” (Part 1)—Why Nongda Fertilizer is Known as a “Chinese Humic Acid Fertilizer Brand”—and “Revamping the Land” (Part 2)—What Is Humic Acid, this installment will explore, from four perspectives, why humic acid needs to be activated.

1. Humic acid must be activated before it can be used.

In the previous installment, we discussed that the raw materials for humic acid are predominantly lignite and weathered coal, also referred to as mineral‑origin humic acid.

Mineral-derived humic acids are complex polymeric mixtures formed over tens of millions, or even hundreds of millions, of years through physical and chemical processes. They exhibit long-term stability and inertness, are largely insoluble, and in some cases are tightly bound to high-valence metal ions or minerals, making it difficult for them to exert their effects directly. Therefore, they must undergo a series of technical activation treatments to cleave carbon chains, re‑assemble branched structures, and enhance their bioactivity.

So‑called activation of humic acid involves employing physical, chemical, biological, and photo‑irradiation methods to remove ash, enhance the humic acid’s grade, extract and separate its constituent fractions, purify and fractionate the humic acid product, and improve the stability, water solubility, and anti‑flocculation properties of humic acid formulations.

Activated humic acid develops numerous functional groups, which act like human hands, capturing and activating otherwise unavailable nutrients in the soil and converting them into plant‑available forms. This significantly enhances nutrient use efficiency in the soil. The more “hands” there are, the greater the activity of the humic acid and the more pronounced its beneficial effects on crops.

2. There is a significant difference between activated and non-activated humic acid.

1. Differences in appearance

Active humic acid fertilizer, when gently rubbed between your fingers, leaves a greasy feel on the palm and becomes shiny and glossy—quite unlike the original fertilizer.

With other humic acid fertilizers, no matter how much you rub them with your hands, the fertilizer remains unchanged.

Active humic acid fertilizer granules have a uniform color throughout.

Other humic acid fertilizers are merely coated on the surface; a simple rub with your hand will reveal their true nature.

2. Internal Differences

When active humic acid is placed in purified water, it dissolves rapidly, forming a dark brown solution.

Unactivated humic acid is insoluble in water; when placed in pure water, it rapidly settles out and forms a precipitate because it lacks reactivity.

Therefore, free humic acid is not the same as active humic acid, and incorporating unactivated humic acid into fertilizers represents a significant waste of resources.

Three: “First look, second rub, third breathe on it, fourth soak in water” — a quick method to distinguish genuine from fake.

Humic acid fertilizers are becoming increasingly popular, creating opportunities for counterfeit and substandard products to enter the market. In response, the China Humic Acid Industry Association has issued a special notice.

According to reports, in order to pass off products as black fertilizer, aside from genuine active humic acid fertilizers, there are two main methods of fraud: one is to add colorants, flue‑gas desulfurization ash, carbon powder, and the like; the other is to use unactivated lignite or weathered coal directly.

So, how can you easily identify genuine, active humic acid fertilizers?

Following the “one rub, two cut, three soak, four check” identification method for controlled-release fertilizers, we now present the “one look, two rub, three breathe on, four soak in water” approach to quickly distinguish genuine from counterfeit active humic acid fertilizers.

At a glance: Active humic acid fertilizers are not very dark in color; most appear grayish-black or dark brown.

Second rub: Active humic acid fertilizer, when gently rubbed between your fingers, feels oily and becomes shiny and glossy.

Three Puffs of Breath: Active humic acid fertilizer—just breathe on it twice to moisten it, or squeeze it gently in your sweaty palm, and the granules will turn a strikingly dark, glossy black.

Fourth infusion: Take a small sample of the granules and place them in a plastic bottle filled with clean water. Allow the granules to fully disintegrate, then observe the color of the resulting aqueous solution; the solution of active humic acid fertilizer will appear tea‑colored or brownish‑tea colored.

Four: How does Nongda Fertilizer Industry, China’s leading brand in humic acid fertilizers, do it?

In the first installment of “Revamping the Land,” it was noted that Nongda Fertilizer Industry was approved to establish the Ministry of Agriculture’s first key laboratory for humic acid–based fertilizers. Moreover, its Technology Center has been recognized as a national-level enterprise technology center, and its humic acid activation technology was awarded the prestigious “China Patent Excellence Award,” firmly establishing Nongda Fertilizer Industry as a truly deserving Chinese brand in the field of humic acid fertilizers.