Bacteria, fungi, protozoa, and other microorganisms living in soil that decompose organic matter, cycle nutrients, support plant health, and suppress pathogens.
Trillions of microbes live in healthy soil. Bacteria decompose organic matter and fix nitrogen. Fungi form relationships with plant roots (mycorrhizae), expanding root surface and nutrient uptake. Protozoa feed on bacteria, releasing nutrients plants can use. Healthy soils have diverse microbial communities; poor soils have few microbes. Compost, organic matter, and avoiding pesticides support soil microbes.
Soil microbes are the foundation of plant health. Supporting them (through compost, minimal disturbance, avoiding chemicals) multiplies their benefits.