The most important element in your garden is one that is often overlooked, ignored, and forgotten. And it’s right under your feet.
All life on earth depends on soil. But only 10% of the earth’s surface is dirt, and topsoil is only about 10 inches deep. This tiny sliver of the earth is a mixture of organic matter, minerals, gases, and organisms. It is teeming with life and is many ways alive itself.
We like to build create our soil layer by layer with a recipe you will find in our article. By creating such a rich mixture, you will have a nutritious medium for your plants to grow. Let’s get right into it so that you can learn everything you need to know about it with this guide on the Green Pinky.
Soil science is the study of its formation, classification, and ecology. It tells us that dirt consists of the following components:
- Mineral content – this is the inorganic part: the sand, silt, and clay. Sand particles are much larger than silt, which is larger than the tiny clay particles. These particles determine its structure and texture. Its structure impacts how well it drains and how nutrients are made available to the plants.
- Organic matter – this is dead plant material – roots, stems, leaves, etc., in various stages of decomposition.
- Organisms – the animals and insects, bacteria, and fungi that feed on the organic matter and cycle the nutrients that are in the plant material back into a usable form for other plants.
- Nutrients – Plants need about 20 nutrients for good health. Plants use these chemicals to complete life functions – from growing the first root to setting seeds at season’s end, these nutrients provide what a plant needs to live. And most of them come from the soil.
- Macronutrients – These are needed and used in large amounts and include hydrogen, oxygen, nitrogen, phosphorus, potassium, carbon, calcium, magnesium, and sulfur.
- Micronutrients – These are needed in smaller amounts: boron, chlorine, manganese, iron, zinc, copper, molybdenum, nickel, sodium, cobalt, and silicon.
The macronutrients nitrogen (N), phosphorus (P), and potassium (K) are the N-P-K that you see on a fertilizer bag and are needed the most after hydrogen and oxygen, which are provided by air and water.
Steps to Building a Live Soil
Step 1: Testing
Tests help gardeners know what’s going on down in the ground. A test can reveal your dirt’s type and structure, nutrient analysis, pH level, and amount of organic matter.
A Quick DIY Test
To determine your dirt type, examine its texture. A simple test anyone can do involves a clear glass jar, a few tablespoons of samples from around the garden, and water.
- Fill the jar half full with dirt, then add water.
- Put the lid on the jar tightly and shake vigorously.
- Let settle for a few days.
The sand, silt, and clay in your sample will separate into layers, which will allow you to see its profile easily. Sand will be at the bottom, silt in the middle, and clay on top. If each section is equal in size, you have the gold standard – loam!
Testing for pH, Fertility, and Health
To determine your pH, fertility, and health, it’s a good idea to do an analysis test every few years.
There are DIY tests you can buy online. However, if you want a more accurate and complete analysis, you can consider getting a professional test from your county extension service or a commercial testing company.
Take three to five samples from a few different spots in the garden and label the location – for example, “vegetable garden'” or “lawn.” If you have different areas you want to be tested, please try to keep samples from each different location separate. This way you can have specific recommendations for each area tested.
If you will be sending into a lab, take your collected samples and either drop it off or mail it to a lab. In a few week, you should have your report.
These test results will tell you:
- pH level. pH stands for “potential for Hydrogen” and tells you how alkaline or acidic it is. Zero is highly acidic, fourteen is highly alkaline, and seven is considered neutral. Most plants like a pH around six or seven. The pH is determined by mineral content, texture, climate, and water. Most of these elements are impossible to change – it’s better for growers to choose plants that will thrive in the dirt they have rather than to try to change the pH!
- Fertility and health. Tests tell growers what nutrients are available in the soil and whether a nutrient is missing or lacking. Tests will also tell you if it is lacking in organic matter.
- Recommendations. Analysis tests offer you advice on what to add. The lab won’t call out a specific product, but the recommendations will let you know how much of a particular nutrient or element you will need to add.
Almost always, a dirt analysis is going to recommend adding organic matter! Healthy soils have a good loamy texture, are nutrient-dense, hold water but are well-draining, and support root growth.
Step 2: Understand The Nutrient Cycle
It may look like plain old dirt, but healthy soil is rich and diverse and very active.
Soil life teems with organisms, all busily recycling dead garden material back into nutrients. It needs protection and continuous replenishment. It also needs organic matter and organisms to break the organic matter down.
It is an ecosystem consisting of:
- Inorganic material that makes up the structure
- Organic matter in various stages of decomposition
- Insects, centipedes, worms, nematodes, microbes, fungi, and bacteria that feed on that organic matter.
Organisms release nutrients back into the dirt in a form that plants can access. This process is called nutrient cycling.
By performing these nutrient cycles, the dirt is able to continue sustaining life.
It Can Be Depleted of Its Nutrients
Soil can become depleted when people break the nutrient cycle.
Take this all too common example:
A home gardener plants flowers and vegetable in his or her garden. The plant takes nutrients out of the soil. At the end of the season, dead plants are removed from the garden to make it tidy and as a garden “clean up”. The dead garden plant is tossed out and the ground is raked clean and smooth. There are now fewer nutrients than when you first started.
Repeat this for a few growing seasons, and you no longer have healthy soil. And it shows: root development is not robust, growth stalls, and vigor is lessened. Insect and disease problems develop.
Many people then resort to chemical fertilizers and pesticides, but there is a better way. We can build soil!
Step 3: Protect and Improve What You Already Have
Before we move onto our recipe, let’s first talk about what you already have in your garden.
Maintaining or protecting your dirt is just as important as building one. To keep your garden in the best shape possible consider the following:
- First, do no harm. Try not to compact the dirt – avoid driving on it with heavy equipment, walking on it, or working it when it’s wet.
- Feed the organisms and microorganisms. Allow organic matter – also known as dead plants, leaves, stems, and roots – to remain in the garden to decompose. (“Decompose” means something is eating it.)
- Put back what you take out. Start a compost pile or bin where dead plants can be recycled and broken down by microbes. You can then add the compost back into your garden’s dirt.
- Grow cover crops. Also known as green manure, cover crops are grown to be incorporated into the soil at the end of their growing season. Plants like annual ryegrass, winter wheat, and clover help replenish both macro-and micronutrients, and convert nitrogen in the air into a plant-usable form (this process is called fixing nitrogen). Cover crops can also help prevent erosion, and their roots create space for air and water to move through the soil.
Step 4: Living Soil Recipe
Natural soil building can take decades, but we can make our own garden mix that is rich in organic matter and feeds the worms, fungi, and bacteria that return the nutrients to your plants.
The Base Mix
- ⅓ part sphagnum peat moss
- ⅓ part perlite or pumice for aeration – this allows for air and moisture to travel through the soil, as well as room for root systems to grow
- ⅓ part high-quality compost and/or worm castings (aka/ worm poop)
You can also add any of the following amendments, depending on your garden’s needs.
- Wood ash – high in potassium and phosphorus, calcium, zinc, manganese, and iron. Useful for reducing acidity; a little goes a long way.
- Kelp meal – dried seaweed brings nutrients from the ocean to your garden – nitrogen, potassium, and phosphorus (N-P-K) plus trace amounts of micronutrients – especially calcium, zinc, manganese, iron, sulfur, copper, and magnesium.
- Crustacean meal – also known as crab meal is another gift from the ocean and provides nitrogen and phosphorus.
- Green manure – cover crops that help fix nitrogen.
Mix Your Ingredients
Gently mix the ingredients, then let your living soil sit – or “cook” – for at least two weeks, or longer if you can. This gives the microbes time to begin breaking down the organic matter and for their colonies to increase.
A word of caution about kelp meal and crustacean meal: raccoons and other gardens marauders might be attracted to the subtle fishy smell. It may be subtle to you, but it is strong to them. Until these products are broken down, keep them where animals can’t get them. Otherwise, they will dig, looking for the fish!
Use this dirt mix in trough planters, containers, raised beds, or as a top dress in your flower beds and vegetable garden.
Keep you’re the organic matter in your dirt in tip top shape by continuing to make more compost.
Step 5: Make Your Own Compost
It’s not all that hard to make your own compost. And making compost is the easiest method of building a healthy soil.
There are lots of articles out there about the ratio of brown to green and rules about how often to turn it, but nature has been composting since plants first began and will do it for you over several months.
What to Put in Your Compost
- Garden waste, fallen leaves, and cut up twigs.
- Scraps of kitchen vegetables.
- Coffee grounds and tea bags.
- An occasional live earthworm.
What Not to Put in Your Compost
- Meat and bones, eggshells, cooking oils (these attract rodents and other animals)
- Noxious or poisonous weeds (like poison ivy)
- Diseased plants (diseases can be spread when you spread the compost!)
- Weeds that have already gone to seed
The smaller the pieces, the quicker the microbes will break them down.
It often takes several months to a year for compost to be “finished.” Finished compost looks like dark, rich, healthy soil.
You can then mix the compost into your garden at the rate of ¼ to 1 cup finished compost per cubic foot of soil.
With consistent applications of compost and organic amendments, poor dirt can become a healthy one. Returning dead plant material to the soil where organisms can recycle it keeps the nutrient cycle going and keeps it alive.
You will soon see improvements in garden health and vigor.
So don’t neglect your soil. Treat it like the living thing it is.