0419 777 606

Healthy soil and worms

Healthy Soil and Worms

How do you know if you have healthy soil?  If your plants are strong and vibrant without fertilizers- that’s a pretty clear indication.  Soil tests are expensive but there is an experiment you can do. This is also a good experiment to do with your children.    Bury your undies. The undies must be cotton or natural fibre, such as linen or, if you have any, silk.  Bury them and if after 6 weeks in your soil, you only have elastic left- you have healthy soil. The life in your soil finds cotton undies very tasty.  If you still have recognizable undies  there is little life in your soil,

Experiment Instructions here

The basic process of forming soil begins with the weathering of rocks and minerals into smaller particles which takes millions of years. Yet crucial for soil health and growing plants, are organic matter and the living part of the soil. They pretty much go hand in hand.

It is almost impossible to imagine how much life there is in healthy soil. Just one teaspoon of healthy soil can hold 100 to 1 billion bacteria, 6 or so fungal strands, several thousand protozoa, a dozen nematodes, up to 100 arthropods, and five earthworms- (small ones).

Healthy soil looks good, a rich chocolaty brown,(although there are many types of soils and each varies in texture and color, for example, soils in the outback are rich red and very fine).  Healthy soil smells good.  In my garden where I grow vegetables, I love to smell the earth.  Not only does it look rich and good, but it can also be rolled like a  piece of spaghetti. It sticks together.  Worms are an integral part of good soil structure.  And healthy soil smells earthy and good.  This smell is due to microbes in the soil.

Healthy soil’s earthy smell is due to the beneficial microorganisms in the soil.  Healthy soil can make you happy.  Contact with healthy soil bacteria can trigger the release of serotonin, a chemical that can make you happy.

Without organic matter, soils turn into dirt. The microorganisms and worms have no food.  Dirt blows away and cannot absorb water and they erode very easily.

Organic matter is anything that is living and has lived. All living things, including us, are made of carbon.  Roots, leaves, twigs, and fallen trees are all made of carbon, and so are animals and humans. All plant material or trees and animals that die, and decompose through the actions of the microorganisms are organic matter and if returned to the soil continue the cycle of adding nutrients to the soil.

An amazing array of thousands of different species of bacteria, fungi, protozoa, nematodes, arthropods, and worms live in the soil, all with different functions in the soil.  Organic matter in soil is chewed and broken down.

There are millions and millions of microorganisms that you need a strong microscope to see, that live underground eating organic matter and eating each other. It’s almost like a war down there.   Worms and other decomposers are at the top of the chain and their poo from chomping their way through all the organic matter, bacteria, fungi, and nematodes creates the soft rich matter in soil that plants love.  And as worms tunnel through the soil they are creating passages for water to seep into and stay in the soil.

Elaine Ingham has created a Soil Food Web illustrating the system of complex interactions between the different species and who eats who. This model illustrates how different organisms interact with each other and with the physical and chemical properties of the soil to create a healthy, thriving ecosystem, right under our feet.  The Soil Food Web also shows how plants, algae, and cyanobacteria,  use sunlight to produce energy through photosynthesis to feed the microorganisms in the soil.

Worms play an important role in healthy soil.  Earthworms outnumber all soil invertebrates (animals that do not have a skeleton)  in both number and biomass, There are more than 7000 species of worms which range in length from an inch to as long as nine feet. Worms are a good indicator of soil health because they are easy to see. The more worms in our soil, the more soil life.


Healthy soil is important to us because our food comes from the soil.  Digging up the soil is particularly harmful. Digging and tilling the soil destroys the structure of the soil and thus its ability to hold water, so when it rains the soil cannot absorb it all. Pesticides and fungicides kill the life in the soil.

Soil microbiomes are incredibly diverse, and play essential roles in soil fertility, nutrient cycling, and plant health.  We know that microorganisms interact with each other in complex ways and many form beneficial relationships with plant roots and protect them from diseases and pathogens. We know that fungi are an essential component of soil ecosystems and particularly of the importance of Mycorrhizal symbiosis providing plants with nutrients in exchange for carbohydrates.  We also know that the microorganism in the soil play an important role in carbon sequestration, that is plants capture CO2 from the atmosphere as they photosynthesize, converting it to carbohydrates and sending this, down through their roots to the microorganisms in the soil.  Its their food and fuels their activities. And thus the cycle continues.

So what are the indicators of healthy soil? They are relatively simple: soil organic matter and the abundance, activity and diverse microbial soil life community and lots of worms.