Start with the Foundation.
Take care of the soil, and the soil will take care of the rest. The soil in your garden is the foundation for everything that happens, and the better you care for it, the better your garden will grow.
In the long run, the success of your garden depends on making healthy garden soil. The more you can do to keep your soil healthy, the more productive your garden will be and the higher the quality of your crops.
Building Healthy Soil
Growing your soil is an investment that you won’t regret. The process requires patience and intention — there isn’t a way to get healthy soil overnight. It takes from 100 to 1,000 years for the Earth to form just one centimeter of soil organic matter naturally.
Luckily, there are techniques gardeners/farmers/humans can implement to speed up this process naturally.
The biggest thing to keep in mind when endeavoring to grow soil is to build organic matter. Organic matter is the ecologically rich portion of soil that works all the magic. It’s sticky — holding nutrients and absorbing water — so that plants can thrive. If you’ve ever seen the dark, black soil of a well-tended garden, that’s the soil you’re striving for. Black soil equals carbon; carbon equals organic matter.
Soil Food Web
Just one teaspoon of soil contains 100 million to one billion bacteria, and that doesn’t even include the protozoa, nematodes, mites, springtails, rotifers, tardigrades, insects, spiders, earthworms, snails, slugs and even birds that make the soil food-web work.
Soil building is the work of the soil food web — the vast community of organisms that live and feed in the ground. As you delve deeper and deeper into growing your soil, tending your garden and living more organically, you will discover the incredibly important role that beneficial bacteria and other microorganisms play in our lives; not just in our gardens, but also in our bodies, our water and the air we breathe.
Soil amendments are organic materials that can be added to the soil to amend its structure, pH and available nutrients. Soil conditioners are amendments that are primarily added to modify the soil structure, creating space for air, water and roots.
Fertilizers primarily supply nutrients to support plant growth and feed the soil’s micro-organisms.
Soil amendments can serve both as fertilizer and soil conditioner. Top dressing with compost and mulch each year is a great way to build healthy soil by adding organic material and biomass. This will aerate the soil, hold in moisture and help contain nutrients.
Practices for Increasing Organic Matter in Soil
- Adding animal manures (raw manures in fall, composted manures in spring)
- Cover cropping
- Compost and vermicomposting
- Reduced Tillage
- Rock Minerals
- Your use of these practices will vary, mostly based on the type of soil you have.
A soil is classified by the ratios of three main soil particles it contains.
Main Soil Particles
Sand — The largest particle. Sandy soils are quick-draining and feel like, well, sand. Gritty and thin.
Silt — A mid-sized soil particle, usually derived from quartz or feldspar.
Clay — The smallest soil particle. Clay soils are common in Appalachia and are characterized by dense, heavy texture.
No garden soil will be strictly sand, silt or clay, but instead a combination of particles. Classifications like “clay loam” or “sandy loam” or “silty clay loam” are a few examples. All soils benefit from continual additions of compost and general building of organic matter to increase aeration, water and nutrient absorption, and microbial life.
You can easily do a soil composition test in a mason jar. Just add garden soil and water to the jar, shake it, then let it settle. After 24 hours, you will clearly see the percentages of sand, silt and clay particles, so you know what your primary soil composition type is.
Other Soil Amendments to Consider
Biochar is a charcoal-like substance that’s made by burning organic material from agricultural and forestry wastes (also called biomass) in a controlled process called pyrolysis. Although it looks a lot like common charcoal, biochar is produced using a specific process to reduce contamination and safely store carbon.
Because of biochar's physical and chemical nature, it has a unique ability for attracting and holding moisture, nutrients, and agrochemicals, even retaining difficult to hold nutrients like nitrogen and phosphorous. Nitrogen tends to run-off regular soils, upsetting ecosystem balance in streams and riparian areas. When added to soil, biochar improves plant growth and enhances crop yields, increasing food production and sustainability in areas with depleted soils, limited organic resources, insufficient water and/or access to agrochemical fertilizers.
Organic matter is only one part of the soil-building story. The other key to restoring the health of our soils is through the process of remineralization. As proficient as plants are, they can’t make the minerals that are essential to human health and nutrition. Rock dust (also known as rock powder, stone dust or soil remineralizer) is finely crushed rock containing micronutrients and trace elements that are important to the life cycle of plants and enhance the ability of beneficial microbes to flourish.
All rock dusts provide minerals for your soil, but different rocks are made up of different minerals. Getting a complete soil analysis done on your soil can help you determine which type of rock dust is best for your needs.
Encouraging organic matter in your soil will improve the soil’s structure, resulting in nice, crumbly soil that will be easier to work, and will make your garden and landscape healthier and more resilient.
(If you want to learn more in-depth practices to building healthy soil, head over to the Organic Growers School website, https://organicgrowersschool.org/ and check out the latest spring conference recordings. Recordings are subject to purchase.)