Search
Contact Us

t: (440) 561 0510

Linkedin Facebook-f X-twitter

Soil health

Also known as
soil quality

Soil health is the continued capacity of a soil to function as a living ecosystem that sustains plants, animals and people. A healthy soil holds and supplies water and nutrients, supports roots and soil life, cycles organic matter and resists erosion.

What is soil health?

The USDA Natural Resources Conservation Service defines soil health as the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals and humans. The definition treats soil as a living system rather than simply a medium that holds nutrients: its physical structure, its chemistry and its biology all interact, and all three determine how well it performs.

Soil health is sometimes called soil quality. The terms overlap; soil health places more emphasis on biology and on how management changes a soil over time.

What a healthy soil does

  • Holds and moves water. It lets rain soak in through good water infiltration, stores it for crops, and drains excess.
  • Supplies nutrients. It holds nutrients against leaching and releases them as crops need them, largely through microbial activity.
  • Supports roots. It has a stable structure, with pores and aggregates that roots and water can move through, free of limiting soil compaction.
  • Sustains soil life. It feeds a diverse soil microbiome, along with earthworms and other organisms that cycle organic matter and build structure.
  • Resists degradation. It withstands erosion, crusting and extreme weather better than a degraded soil.

How soil health is measured

No single test captures soil health, so assessments combine indicators:

TypeExample indicators
PhysicalAggregate stability, infiltration rate, bulk density, penetration resistance
ChemicalpH, nutrient levels, cation exchange capacity
BiologicalSoil organic matter, active carbon, soil respiration, soil protein

Laboratory packages such as Cornell’s Comprehensive Assessment of Soil Health combine several indicators into a scored report. Because many indicators change slowly, soil health is best tracked on the same fields over several years.

Principles for improving soil health

The NRCS summarizes soil health management in five principles:

  1. Minimize disturbance, physical, chemical and biological, including tillage.
  2. Maximize soil cover with living plants or residue.
  3. Maximize biodiversity through crop rotations and diverse cover crops.
  4. Maximize continuous living roots, which feed soil organisms through the year.
  5. Integrate livestock where practical.

Practices such as no-till farming, cover cropping and diverse rotations put these principles to work, and they are central to regenerative agriculture.

Why soil health matters for yield

Healthy soils buffer crops against stress. Better infiltration and water holding reduce the effects of drought and heavy rain; better structure allows deeper rooting; active biology supports nutrient cycling and nutrient use efficiency. Improvements usually build over years rather than one season, and results vary by soil type and climate.

Soil health at Locus

Locus Agriculture describes its biologicals and its Unpac biosurfactant soil conditioner as supporting soil health and root-zone function, alongside fertilizer efficiency and yield.

Frequently asked questions

Soil fertility refers to the soil’s supply of plant nutrients. Soil health is broader: it includes fertility, but also structure, water movement and biological activity, and how the soil functions as a whole.

Some indicators, such as active carbon and soil respiration, can respond within a season or two. Others, especially soil organic matter, change slowly and may take several years of consistent management to shift measurably.

There isn’t one. Soil organic matter and aggregate stability are among the most informative individual indicators, but soil health is best assessed with a combination of physical, chemical and biological measurements.

  • Soil organic matter SOM

    Soil organic matter (SOM) is the fraction of soil made of living organisms, fresh and decomposing plant and animal residues, and stable, well-decomposed material called humus. Although it usually makes up only a few percent of soil by weight, it strongly affects fertility, structure and water holding.

  • Soil compaction

    Soil compaction is the pressing together of soil particles, which reduces the pore space between them. Compacted soil holds less air, lets water in more slowly and physically resists root growth, which can reduce crop yield.

  • Water infiltration

    Water infiltration is the process by which water on the ground surface, from rain or irrigation, enters the soil. The infiltration rate is how fast that happens, usually in inches or millimeters per hour. Poor infiltration leads to runoff, ponding and erosion.

  • Soil microbiome

    The soil microbiome is the community of microorganisms living in soil, including bacteria, archaea, fungi, protists and viruses. These organisms decompose organic matter, cycle nutrients, build soil structure and influence plant health.

  • Regenerative agriculture

    Regenerative agriculture is an approach to farming that aims to improve soil health and the wider environment over time, rather than simply sustaining them, through practices such as minimal tillage, cover crops, diverse rotations and integrating livestock. It has no single legal definition.

  • Cover crop

    A cover crop is a crop grown mainly to protect and improve the soil rather than for harvest, typically planted between cash crops. Cover crops reduce erosion, add organic matter, can capture or fix nitrogen, suppress weeds and support soil biology.

Sources

  1. Soil Health, USDA Natural Resources Conservation Service
  2. Comprehensive Assessment of Soil Health, Cornell University Soil Health Laboratory