It’s not just dirt! Your soil is alive and the foundation of every lawn, garden, and woodland. It is filled with Mother Earth's Soul, and our collective souls. The creatures living in the soil are critical to soil and plant health. They are central to decomposition and nutrient cycling that affect root growth, affect soil structure, erosion, and water availability, and protect plants from pests and disease.
The soil community
The soil community is made up of incredible diversity, including bacteria, algae, fungi, and beneficial nematodes to the visible earthworms, insects, small vertebrates—and of course, plants! As these organisms eat, grow, and move through the soil, they create a healthy environment for your plants.
These microscopic cells usually grow as long threads and strands called hyphae, which push their way between soil particles, roots, and rocks. Hyphae sometimes group into mycelium. Fungi perform important tasks in the soil including moving water and nutrients, decomposing organic matter, and disease suppression.
Mycorrhizal fungi colonize the roots of plants. In exchange for carbon from the plant, mycorrhizal fungi help bring soil nutrients and water to the plant. It is thought that these fungi also help plants communicate with each other.
A teaspoon of healthy soil could contain between 100 million and 1 billion bacteria. Bacteria are decomposers that convert energy in the soil’s organic matter into forms that benefit the entire soil food web. Some bacteria form symbiotic relationships with the roots of legumes, creating nodules. The plant supplies simple carbon to the bacteria, and the bacteria converts the nitrogen from the air into a form the plant can use. When the leaves and roots from the host plant decompose, soil nitrogen increases in the surrounding area.
A single spade full of healthy garden soil may contain more species of invertebrates than can be found above ground in the entire Amazon Rainforest. The invertebrates improve the soils structure, increase pore space in the soil, which improves aeration and drainage. Studies have shown that reintroducing invertebrates into degraded soils improves its health and promotes recolonization of more species.
A soil’s structure refers to how particles in the soil are grouped together. They are bound together by physical, chemical and biological processes (freezing and thawing, wetting and drying, plants roots, fungi, and organic matter).
Types of soil
Soil is a mixture of sand, gravel, silt, clay, water, and air. The different amounts of these ingredients determine how well the soil is held together and its type.
Clay soils are rich in nutrients and very fertile. If you can break it up sufficiently by adding organic matter, this is a great soil to start with. Breaking down the clay into crumbs makes the water and nutrients held in the clay more readily available to plant roots. It also makes the soil warmer, easier to work, and less prone to compaction.
These light soils are usually low in nutrients and lose water very quickly. Boost the water and nutrient holding capacity of your soil by adding a lot of organic matter to bind the loose sand into a loamy mix. With sandy soil, you may have to add fertilizer to give your plants an extra boost.
These soils are made up of fine particles that can be easily compacted by walking on them or using garden machinery. If left exposed to the elements without plant cover, these soils are prone to wind erosion and being washed away. However, they contain more nutrients and hold more water than sandy soil. Organic matter will help this soil type as well.
This soil type is a gardener’s dream. They are the perfect balance of soil particle types. Even though they are very good growing soils, it is important to regularly add organic matter to maintain its health.
Alkaline vs Acidic Soils
If a soil’s pH is below 7, the soil is considered acidic. If the soil’s pH is above 7, it is considered alkaline. Garden and vegetable plants like to grow in neutral to slightly acidic soil. Changing the soils pH will only happen over a VERY long time. Just think, it took millions of years to get that way in the first place. Adding an amendment will only change the pH slightly and temporarily.
Build healthy soil
The best way to build healthy soil is to identify your soil type. The best way to initially test the type of soil you have is by touching it and rolling it in your hands. Then, have your soil tested by your local extension office.
Adding organic matter is a great way to improve your soils health. Organic matter is something with organic compounds that you add as a soil amendment. It is decaying plant or animal material, and includes: compost, green manure, leaf mold, kitchen scraps, cardboard, and paper. Organic matter added to your garden soil improves the structure, which makes it easier to retain or release water, nutrients, and air. Also, the more beneficial organisms and microorganisms that are in your soil, the less the bad organisms will be able to survive.
Compost is decomposing organic matter. It is nature's way of breaking down and recycling leaves, vegetable scraps, twigs, and other organic matter into a rich soil amendment. There are three ways to compost:
Cold composting/Chop & Drop
Cold, or passive, composting uses many of the same type of ingredients as hot composting and requires less effort, yet the decomposition takes substantially longer—a year or more. However, this is also Mother Nature’s way of composting.
The quickest way to produce rich garden humus is to create a hot, or active, compost pile. It is called “hot” because it can reach an internal temperature of 160°F (140°F is best). The size of the pile, the ingredients, and their arrangements in layers are key to reaching your desired outcome.
Red worms in bins feed on food scraps, yard trimmings, and other organic matter to create compost. The worms break down this material into high quality compost called castings. Worm bins are easy to construct and are also available for purchase. The bins can be sized to match the volume of food scraps that will be turned into castings.
It typically takes three to four months to produce usable castings. The castings can be used as potting soil. The other byproduct of vermicomposting known as “worm tea” is used as a high-quality liquid fertilizer for houseplants or gardens.
Building healthy soil is up to Mother Nature and you. The health of your soil determines the health of your plants. The best way to amend your soil's structure and to provide oxygen, moisture, and nutrients is to add compost and top dress with mulch. Begin by testing your soil’s pH and nutrient content. With time and patience, your garden soil and the plants you grow will reward you with beauty, abundance, and health.