What is Soil Aggregation & How to Improve It

May 21, 2025

Growers struggling with poor drainage, unhealthy plant development, and difficulty working the soil are likely experiencing soil with poor aggregation. The good news is, your soil issue doesn’t have to just be “fixed”, but your soil can be a resource for you to grow even healthier crops than you are now! Let’s dive into soil aggregation and how we can help improve it, naturally. 

What is Soil Aggregation & Soil Aggregates?

Soil aggregation refers to the process where individual soil particles of sand, silt, and clay bind together to form larger clusters known as aggregates. These aggregates are stabilized by organic compounds produced by soil microbes, plant roots, and fungi, creating a porous structure that facilitates air and water movement, root penetration, and microbial activity.

The Importance of Soil Aggregates

Natural soil aggregates are formed through biological processes involving plant roots, microbial exudates, and fungal hyphae. These aggregates enhance soil structure, promoting better water infiltration, reduced erosion, and improved root development. They also play a critical role in carbon sequestration, aiding in climate change mitigation.

Benefits of Well-Aggregated Soil

• Enhanced Water Retention: Aggregated soils hold water more effectively, reducing the need for frequent irrigation.

• Improved Nutrient Cycling: Aggregates provide habitats for microbes that decompose organic matter, releasing nutrients for plant uptake.

• Increased Root Penetration: The porous nature of aggregated soil allows roots to grow deeper, accessing more nutrients and water.

• Erosion Resistance: Stable aggregates reduce soil erosion by protecting against wind and water forces.

How to Improve Soil Aggregation

The key to improving soil aggregation is deep roots and living soil. In order to achieve this you will need to do the following:

1. Maintain Continuous Living Soil

Keeping living plants in the soil year-round ensures a constant supply of root exudates which are sugars and other organic compounds that feed soil microbes. These microbes produce substances like glomalin, which bind soil particles into stable aggregates.

2. Apply Microbial Inoculants like Algae

Utilizing microbial inoculants enhances microbial diversity and activity in the soil. These inputs support the formation of natural soil aggregates by stimulating microbial processes that produce binding agents. Algae is a great natural way to enhance the activity in your soil as well as provide added nutrients that will help your crops grow stronger. Ensoil Algae is a great product to jumpstart the soil aggregation process. 

3. Reduce Tillage Practices

Minimizing soil disturbance preserves existing aggregates and maintains the habitats of beneficial soil organisms. No-till or reduced-till farming practices help in sustaining soil structure and promoting aggregation.

4. Incorporate Cover Crops

Planting cover crops adds organic matter to the soil, protects against erosion, and supports a diverse microbial community. The roots of cover crops also aid in the formation of soil aggregates. Consider a cover crop seed blend specific to your farming operation. 

5. Avoid Overuse of Chemicals

Excessive application of synthetic chemicals can harm soil microbial communities, disrupting the processes that lead to soil aggregation. Opting for natural inputs helps maintain a healthy soil ecosystem conducive to aggregation.

Sustaining Soil Aggregation

Just because your soil has become well-aggregated doesn’t mean that it can’t become compacted again. Soil aggregates are only stable for 30 days. If there are no sugars being pumped into the soil, the active carbon levels are not being replenished, and eventually the soil life doesn’t have enough to eat – so, they stop maintaining the soil aggregates. 

In order to maintain well-aggregated soil, you will need to monitor your soil, keep your soil covered, and limit disturbance. Ensure your soil is active and living and you can rest assured you will have well-aggregated soil for seasons to come.

Talk to a Soil Expert

At Keystone Bio-Ag, we specialize in regenerative farming, which starts with the soil. We help farmers and commercial growers get the most out of their soil and their crop with sustainable farming best practices. If you are looking to improve your outputs while maintaining healthy soil, reach out to one of our regenerative agriculture consultants.