Why You Should Use Humic Acid In The Garden

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Using humic acid in the garden
Using humic acid in the garden

Why You Should Use Humic Acid In The Garden

In recent years we have seen a push towards organic gardening. But organic gardening when done incorrectly can lead to nutrient deficiencies and ultimately low yields. This is why humic acid is starting to make its way into the world of gardening both organically and conventional. This gardening in Canada article looks at why you should use humic acid in the garden.

If you are new to this blog my name is Ashley and I am a soil scientist. I am located in a Canadian Zone 3 and a USDA Zone 4. I write articles, make YouTube videos, Instagram posts all designed for Canadians and Cold Climate gardeners using science-based methods. If you are looking for anything specific be sure to let me know in the comments down below.

If you want to learn more about humic acid and houseplants check out this article here.

I will start this article out by saying humic acid can be sourced from a wide variety of sources. This means not all humic acids are ethical, nor are they created equally! The only humic acid I use is called Kaytonik. I use Kaytonik both outside and indoors. I have noticed awesome results and healthier soil. If you want to grab Kaytonic fertilizer check out this link here. Also, be sure to follow them on Instagram or Facebook.

What is Humic Acid?

Humic acid is not a fertilizer, it is a conditioner for the soil and the plant. Some refer to it as a biostimulant because it is able to aid in chemical reactions needed for nutrient uptake. Biostimulants help with increasing nutrient uptake via better nutrient utilization. This increase in utilization means the plant is better at handling stress from the weather, pests and diseases.

Humic acid is not well understood by the scientific community and is actually highly debated! Some believe it is not naturally occurring at all and others believe it exists but is impossible to extract. The commercially available forms are simply peat or coal that has been exposed to highly alkaline solution. This means the resulting compound is a group of compounds not a single acid. 

Because humic acid is considered a group of compounds the consistency and effectiveness between products can vary. The compounds within the product will vary based on the source of the organic material & the alkaline mixture used. The main elements within every mixture include carbon, hydrogen and oxygen. The carbon in humic acid is the key to why humic acid is so valuable to our plants.

Chemical Benefits Of Humic Acid

When you think about humic acid and organic gardening the word chemical benefits does not come to mind. But the truth is that humic acid has unique chemistry when applied to a soil system. Humic acids are excellent chelators of soil minerals and nutrients.  

Chelation is a process where large molecules that are not bioavailable become available for plant uptake. In many cases with clay soil, there is an abundance of nutrients waiting to be utilized. The issue is that the nutrients are not in a bioavailable format for uptake. 

Humic acid allows for a process called chelation where nutrients are made more available for the plants. This results in higher yields and few cases of nutrient-related diseases such as blossom end rot.

For example, Humic acid increases phosphorus (P) availability and uptake. Phosphorus is often bound tightly with nutrients such as iron (Fe) and aluminum (Al). This makes for a molecule that is much too large for plant uptake. Humic acid turns these compounds into water-soluble bioavailable forms for plant uptake

Increased Cation Exchange Capacity When Using Humic Acid

Another benefit of Humic is an increased cation exchange capacity (CEC). The CEC is the cation exchange capacity of the soil. Meaning CEC is a measure of a soil’s ability to hold positively charged ions called cations. Most plant nutrients are cations or positively charged ions.

The CEC of soil helps molecules within the soil hold onto hold nutrients. Similar to how a battery holds a power charge. Humic acid is able to increase the natural nutrient holding capacity of the soil. For clay soil gardeners this is simply an added bonus. But for gardeners in sandy or sandy loam soils, this is a major game-changer. 

Humic acid in the presence of soil prevents nutrients from leaching out of the soil. This ultimately means it is more available to the plant. We talked about this also in the houseplant article and how it relates to exponential growth. 

Changes In Soil pH When Using Humic Acid

Humic acid also has the ability to buffer soil pH. I have spoken about the importance of soil pH and nutrient uptake over on my youtube channel many times. With humic acid, we can observe a decrease in the pH of acidic soils and increase the pH of basic soils by absorbing or releasing hydrogen ions. This buffering capacity allows for a more neutral pH. In turn, plant nutrients are more available. For more on soil pH and nutrient uptake check out Gardening In Canada on YouTube.

Physical Changes In The Soil

Humic Acids are known as soil conditioners, not fertilizers. This means they improve soil structure and function. Humic acid due to its chemical properties is able to increase soil aggregation. Soil aggregation means that soil particles clump together and reduce soil losses through weathering. Over time rotting roots, bugs and fungi will help to create air pockets and increase aeration within the soil. 

This change in physical soil structure is beneficial to sandy soils because it helps with water retention. But it is also valuable to clay soils because it reduces the chances of topsoil losses as well. This ultimately benefits the plants regardless of the soil type below. 
If you want to grab some humic acid for your houseplants check out this link here. If you want to learn more about humic acid in the garden check out this link here.