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What Is Humus? Plus, How To Make It Yourself
September 15, 2019
Considering humus is one of the most important elements in your garden’s soil, it doesn’t seem to get a lot of attention. In fact, many people haven’t heard of humus and just consider it to be compost.
Humus, which has become known as “black gold” for farmers, is what’s left when your compost has decomposed to create a dark, nutrient-rich soil. Composting to create humus-rich soil helps to foster the principles of regenerative agriculture by enriching the soil and ecosystem.
What Is Humus? (What Is It Made of?)
Humus (pronounced HUE-mus) is known as the life of your soil — it means “earth” and “ground” in Latin. It’s the result of decomposed compost, or organic matter, and it’s rich in microorganisms that allow plants to absorb nutrients.
When plant and animal matter in compost or soil fully decays, this creates humus. It’s made up of what are called humic substances and has a spongy, porous consistency.
The humic substances that are found in humus include:
- Humic acid
- Fulvic acid
- Humin
When these humic substances are added to soil, farmers often see significant increases in crop yields. Humic acid and other substances serve as a medium for transporting nutrients from the soil to the plant. They deliver water and vital nutrients to the roots of the plant.
Adding this important matter to topsoil is one of the basic actions of permaculture, as it contributes to soil regeneration.
Humus vs. Compost
The terms humus and compost are often used interchangeably. Humus is fully decomposed compost. Even while you no longer see the waste products you added to your compost, it actually takes years for these goods to fully decompose and become humus.
Even after you add compost to your garden, it will continue to decompose as bugs, bacteria, fungi and microorganisms eat away at it. These microscopic actions slowly turn the compost soil into nutrient-rich material.
Why Humus Is Important (Benefits)
- Retains moisture in soil: Humus makes soil spongy so it’s able to hold water when it needs it and spring back after it’s been soaked. Humus-rich soil, which holds 80–90 percent of its weight in moisture, can increase its drought resistance.
- Loosens soil: Humus in soil allows for better aeration and drainage. When soil doesn’t have enough of this material, it becomes too compacted and may even form a crust that doesn’t allow air, rain or water to pass through. Because it has a crumbly consistency, this also allows oxygen to get through the soil and reach the roots of the plants.
- Keeps soil warm: Because soil rich in humus is dark brown in color, it attracts sunlight. This is particularly helpful during the cooler months, and it helps to warm up cold soil.
- Supplies nutrients for plants: This nutrient-rich material is made up of soil organisms that are feeding on the organic matter content. When you use compost or manure to create humus, this increases the microbial activity of soil and provides its nutrients. One of the most important nutrients in humus is nitrogen, which research shows is one of the most important nutrients in natural and agricultural ecosystems.
- Protects the soil: The biochemical structure of humus allows it to act as a buffer, maintaining healthy conditions and preventing toxic substances or heavy metals from entering the ecosystem. It may even help to prevent disease in plants.
- Helps to maintain mycorrhiza: Mycorrhiza is a beneficial fungus that bolsters the health of plant roots. These fungi are considered natural biofertilizers that supply soil with nutrients and pathogenic protection.
How It Is Made
In nature, humus is made when leaves, twigs and animal remains break down into basic chemical elements. These elements within the soil serve as nutrients for plants, allowing them to live and grow. Once the matter is decomposed, the nutrient-rich matter is created. Earthworms help to mix it with minerals in the soil.
On farms, humus is made by adding manure to soil. If you don’t have access to manure from cows, goats or horses, then humus can be made with compost.
Composting involves collecting decaying material that will break down and turn into nutrient-rich soil. To make nutrient-rich material, composting in your home garden and adding it to your soil once the matter is broken down will improve the growth and health of your plants.
How to Increase Humus
To increase humus, you’ll need to create a compost bin that collects garden waste. To make compost, simply add leaves, weeds, grass, plant clippings, vegetable waste and more into an outdoor heap or bin.
Some items that you can add to your DIY compost to speed up the humus-making process include:
- Veggie cores and waste
- Chopped corn cobs
- Fruit waste
- Molded bread
- Coffee grounds
- Tea leaves
- Grass clippings
- Branches
- Twigs
- Dried leaves
- Ripped up, untreated cardboard
Be sure to keep the compost pile moist so the decaying process can continue. During dry spells, you can wet your compost with a hose. This will help to break down the organic matter.
Turning your compost pile is another great way to speed up the decaying process so it will become humus-rich soil. Once the clippings and waste in your compost have broken down completely and all that’s left is loose and crumbly soil, it’s ready to be added to your plant beds.
Some other ways to increase the amount of nutrient-rich matter in your soil includes tilling the soil and using concentrated nitrogen fertilizers.
Can You Have Too Much? (Potential Downsides)
Although this nutrient-rich matter is known to significantly increase plant and crop yields, there may be some downsides to having too much humus. Because it retains water, the soil may become too moist in very wet conditions.
That being said, most farmers and gardeners have to work to preserve this nutrient-rich matter by composting, fertilizing and tilling their soil.
Final Thoughts
- Humus is called “black gold” because it serves as the life in soil.
- It’s nutrient-rich material that exists when organic matter decomposes. Because of its porous texture, it retains water and loosens soil. It also supplies nutrients, protects plants and increases plant yields.
- To increase this important material in your soil, you can create a compost by adding yard and kitchen wastes to a moist pile. Once the organic matter decays, it becomes nutrient-rich material that can be added to your soil.
