soil microbiome

Soil health is the cornerstone of plant, animal and human health. Regenerative farmers take many actions to repair, protect and enrich soil, and to build new soil. Regenerative farmers:
  • Keep the soil covered at all times.
  • Increase soil moisture-holding capacity by increasing organic matter in the soil.
  • Encourage a diversity of plant life rather thana single species monocrop.
  • Use these and other techniques to build resistance to erosion and sun-bleaching.
These, and other generative farming practices such as managing grazing and minimising tillage, all operate to build soil health at the microbial level. With up to a billion bacteria in one gram of soil, microbes are small, but they are mighty!

Rhizosphere

A super-active community of exchange.
Right next to a plant’s roots, in the soil, there is a zone of activity called the rhizosphere. In the rhizosphere, microbes feed on carbohydrates (root exudates, or dead bits of root ‘shed’ or ‘sloughed off’ by the plant). In exchange, microbes and fungi perform different functions for the plant such as transporting water, fixing nitrogen or delivering trace elements and minerals to plant roots. It’s a super-active, tiny community of exchange under the soil and it works best when there are many types of microbes.

microbes around the roots

Microbes don’t work alone.
Microbes don’t work alone. They generally organise into diverse groups of different microbe species. Each plant species supports different types of microbes, so diversity in the species of plants above ground is crucial for diversity below ground. It’s like making sure every member of the team shows up to play and all positions are filled.

Humans have microbes (good ones, too!) living on our skin and inside us. So do plants. Beneficial microbes live on each plant’s leaves and roots, and inside plant tissues. Microbes help each plant to better resist biotic and abiotic stresses. That means the plant can better resist the attacks of living things like pests and diseases,and the stress of non-living events like drought, salinity and waterlogging.

SEED

Microbes protective properties
Like people and plants, seeds contain a diverse community of bacteria and fungi. These microbes on and inside the seed protect the seed until germination. At germination, a plant and its microbes form an association with the soil microbiome. Most commercial food plant seeds have received some chemical treatment designed to protect the seed from diseases and soil pathogens. These treatments interrupt the development of healthy microbe-plant associations. We want to keep this community of microbes healthy so that the moment a plant germinates, it begins to develop strongly, and it is resistant to pests, cold and heat stresses right from the start.

Worm tunnels

Soil's aqueduct system
Worm tunnels aerate the soil and enable water to penetrate. Worms line their tunnels with a microbe-rich slime. As they eat organic matter they deposit worm castings in their tunnels, which adds to the community of microbes in the soil and provides rich food for plant roots, right where they can get it.

Regenerative farmers disturb the soil as little as possible, in order to preserve the structure of the soil built by worms, other invertebrates and insects, and the soil microbiota.

Reducing the amount of tillage keeps the soil communities intact and does not expose them to heat, cold, sun, wind and predators.