The rich ecosystem of living soil cultivates a nutrient-rich environment to promote plant growth. This is done by a symbiotic relationship with microorganisms, organic matter, and minerals.
Just a handful of soil can contain billions of bacteria, yards of fungal filaments and scores of nematodes. These organisms form a complex food web that forges pathways that allow plants to access premium nutrients and reach their genetic potential – just as Mother Nature intended.
Compost
As a gardener, you’ve likely heard about the advantages of growing in living soil, but may not fully understand how the complex ecosystem of microorganisms, organic matter and minerals cultivates a nutrient-rich environment that promotes plant growth. In this comprehensive guide, you’ll learn about the vital components that comprise a healthy living soil system and tips for developing and preserving your own, creating a self-sustaining growing environment.
While many people think of soil as a lifeless, inert material, it actually teems with millions of tiny organisms working to make the most of the rich chemical and mineral components hidden below ground. This community of beneficial organisms, including bacteria, fungus, protozoa and nematodes, works together to break down organic materials and make them available to plants.
To help keep this vital web of organisms healthy, compost is essential. Compost is made by combining brown materials like dead leaves, twigs and branches with green materials such as grass clippings and fruit and vegetable scraps. The decomposition process takes place naturally when these materials are layered together and exposed to the elements, but composting accelerates and intensifies the natural process.
The result is a nutrient-rich material that looks and smells like dirt, but has much more power than your typical mulch or topsoil. It’s a powerful tool that can be used to fortify your soil, increase crop yields, and eliminate the need for synthetic fertilizers.
Compost also helps reduce the amount of waste that ends up in landfills, as it recycles and reuses organic materials rather than sending them to a garbage dump. Some states have even passed laws requiring that food scraps and other organic materials be diverted from landfills and recycled through the composting process. For more information, check out these fact sheets on the Environmental Law Institute’s website (pdf) or this resource listing composting policies by state.
Worm Castings
Worm castings, also called vermicompost, earthworm compost or simply worm poop, are one of the most beneficial soil amendments for all types of gardening. They contain an array of minerals and a vast amount of microorganisms, all of which are very beneficial to soil health. These are the ingredients that give worm castings their superpower, allowing them to boost plant growth and yield without the unhealthy side effects of chemical fertilizers.
What makes worm castings different is that they are made from the orchestrated dance between earthworms and organic material. Earthworms munch on a buffet of food – kitchen scraps, yard waste and other organic matter, which is then passed through their digestive tract and transformed into tiny, nutrient-rich pellets. The resulting worm castings are full of plant growth hormones, essential nutrients and humic acids, which all work together to improve the quality of soil.
The humic acid in worm castings helps the soil to hold water and provides a medium for beneficial microorganisms to thrive. This creates a healthy, living soil environment that is teeming with a multitude of microorganisms that support healthy plants and make it easier for them to absorb the nutrients they need.
These microorganisms are responsible for promoting healthy root systems in plants which help them to absorb the nutrients in the soil, resulting in increased crop yields and improved plant health. They are also known to suppress diseases and pests. The benefits of using worm castings for gardeners are enormous.
When choosing a worm casting product, it is important to look for ones that are high in quality. A good indicator is the ratio of castings to dirt and other refuse – the higher the percentage of worm casts, the better. Another thing to check is that the castings are moist and free of rocks and other debris. A simple test is to mix them with water – the best quality castings will dissolve quickly into a nutrient-rich solution.
When adding worm castings to the garden, it is best to use them with other soil enriching amendments to get the most out of them. A common recommendation is to use them in a 1:3 or 1:4 ratio with potting soil, planting mix or garden soil.
Microorganisms
The soil is teeming with billions of microscopic organisms that are vital to life on Earth. They are primary decomposers of organic material and recycle nutrients. They also provide nitrogen through a process called nitrogen fixation. They produce humus, which is an important part of the soil. They provide food for all the other organisms in the soil, resulting in a symbiotic relationship that promotes healthy plant growth and helps the ecosystem function.
The most common types of microorganisms found in the soil include bacteria, fungi and protozoa. Some of them are able to break down dead organisms, animal waste, and plant debris (or “biomass”) into simple elements that can be used to build new plants and animals. This is why, if you see dead flowers or vegetable garden scraps rotting in the ground, they are actually being recycled by these tiny organisms.
Other microorganisms help to form a network of fungi, or mycorrhizae, that create underground pathways for plants to communicate with each other. This system allows plants to receive the nutrients they need without having to wait for them to be delivered by other organisms. It also means that less water is needed, and the plants can grow to their genetic potential without being limited by tedious feeding schedules.
All of these organisms are part of a multi-path food system, or food web, that is much more complex than a traditional food chain. This is because many of these organisms interact with each other and with the plants and animals that live above them. For example, there are nematodes that kill other nematodes and fungi that feed on nematodes. This creates a natural balance that prevents any one organism from taking over the soil.
In a healthy living soil, the diversity of the organisms is such that no single organism dominates the entire ecosystem. This is why it is so important to plant a variety of crops and to rotate them each season. By doing this, you can promote the health of the soil and keep it teeming with the life that is so important to all of us.
Minerals
Soil is a living ecosystem teeming with microorganisms that work together in a symbiotic relationship to cultivate a rich nutrient-rich environment to promote plant growth. This underground ecosystem, sometimes called the soil food web, is a central part of regenerative farming and gardening practices.
Scientists have estimated that soil is home to 59 percent of all life, from tiny microorganisms to larger mammals. This makes the soil the most biodiverse habitat on Earth. The soil food web is made up of a network of organisms that help break down organic matter, recycle nutrients and aerate the soil. It also provides protection from disease and pests.
These organisms get their nourishment from crop residues and other organic materials that are added to the soil from off-field sources. They are primarily secondary consumers that feed on bacteria, fungi, protozoa and organic molecules dissolved in the soil water. These organisms also help with the mineralization of nitrogen, which is important for plant growth.
Some of the most important minerals are sulfides, oxides and carbonates. Sulfides, for example, are minerals formed from sulphur combined with other elements (excluding oxygen). Sulfur-containing minerals include galena and pyrite, commonly found in metal ores. Oxides are minerals formed from oxygen and other elements, such as iron oxides (rust) and aluminium oxides (aluminium). Carbonates are the most abundant of all minerals. They are composed of carbon and other elements such as hydrogen, oxygen, carbon dioxide and magnesium.
When the soil food web is working in balance, the resulting nutrient-rich soil provides plants with a natural buffet of premium nutrients, which enables them to reach their genetic potential. In contrast, individuals without access to healthy soil must mimic the natural environment by feeding their crops a set menu of chemicals and supplements.
The best way to grow nutrient-rich plants is to cultivate the health of your own soil. This means avoiding synthetic fertilizers and instead prioritizing the building up of organic material to encourage healthy microbial activity. It also means minimizing soil disturbance and practicing no-till or low-till methods to preserve the integrity of the soil food web and minimize soil erosion. This approach nurtures biodiversity, sequesters carbon and reduces environmental impact.