The Response of Plants to Humic Acid

Nutrition

• Humic acid is made up of colloids, which are substances composed of tiny particles held in a gel-like mass. It's sticky and absorbent, and engulfed in several negatively charged particles that attract positively charged chemical particles, many of which are important plant nutrients including calcium, magnesium, potassium, and hydrogen. As the plant takes up nutrients, the colloids release more nutrients ensuring a steady supply of vital plant nutrients. Humus holds a great deal more plant nutrients than other soil colloids, making it critical for building and maintaining soil fertility.

pH

• Humic acid plays no great role in soil pH (otherwise known as its acidity) because it is insoluble in water. This is beneficial for both plants and soil organisms, which don't tolerate rapid pH changes. Commercial fertilizers often change the soil's pH which can negatively impact the plant that requires a certain pH level. Adding humus provides important nutrients while maintaining a stable pH.

Root System

• A plant's root system benefits dramatically from humic acid, making it more extensive, sturdy and vigorous. A stronger, healthier root system means that the plant can search for and uptake nutrients and water more efficiently. And the healthier a plant is, the better it fights off diseases and pests.

Water Retention

• Humic acid increases a plant's drought tolerance due to the clay-like behavior of the colloids. Humus can hold the equivalent of 80 to 90 percent of its weight in water giving it the ability to hold moisture without becoming soggy. This is especially beneficial for plants living in dry climates and for plants requiring a high level of moisture.