Biochar has become a hot topic in regenerative agriculture for its many beneficial properties in improving soil health. But biochar has actually been celebrated and applied to soils for many millennia. In fact, pre-Colombian people were making biochar over 6,000 years ago in the Amazon basin, resulting in what is still some of the world’s most fertile soil, known as Terra Preta.
What is Biochar?
Biochar is a granular carbon substance that is produced by heating organic biomass, such as wood, in the absence of oxygen (aka pyrolysis). It is a porous, charcoal-like substance that has a number of benefits when added to soil in a garden.
Benefits of Biochar
One of the primary benefits of biochar is its ability to improve soil fertility.
Biochar’s high surface area and porous structure can help to retain water and nutrients in the soil. When added to soil, biochar can increase the cation exchange capacity (CEC) of the soil, which means that it can hold onto more positively charged ions such as calcium, magnesium, and potassium. This can help to provide a more stable and nutrient-rich environment for plants to grow. Other benefits of Biochar include:
- Enhanced soil structure: The porous structure of biochar can also help to improve soil aeration, drainage, and texture. This can help to create a more hospitable environment for plant roots, which can lead to healthier and more robust plants.
- Increased microbial activity: Biochar can act as a habitat for beneficial microorganisms such as mycorrhizal fungi and bacteria. These microorganisms can help to improve soil health and nutrient cycling, which can benefit plant growth and productivity.
- Reduced greenhouse gas emissions: Biochar can also help to reduce greenhouse gas emissions and mitigate the effects of climate change. When organic materials are heated to produce biochar, the carbon that is contained in those materials is stabilized and stored in the biochar. This means that the carbon is not released into the atmosphere as carbon dioxide, which is a major contributor to climate change. This carbon-negative cycle is also known as carbon sequestration.
How to Use Biochar to Amend Your Soil
- Before adding Black Magic Biochar to your soil, make sure to remove any weeds or debris, loosen the soil with a garden fork or tiller, and add any necessary amendments such as compost or fertilizer.
- Biochar can be added to soil in several ways, including broadcasting it across the soil surface, mixing it into the top layer of soil, or applying it as a side-dressing around plants. The amount of biochar to add depends on several factors such as soil type, plant species, and the intended use of the soil. As a general guideline, you can start with 10-20% biochar by volume of the soil, but it's always best to start with a small amount and gradually increase the dose.
- Once you have added biochar to your soil, water the soil thoroughly to help the biochar settle into the soil and begin to absorb moisture.
- After adding biochar to your soil, monitor the soil moisture levels and adjust your watering schedule as needed. Over time, the biochar will begin to interact with the soil and microbes in the soil, so it's a good idea to test the soil periodically to see how it is performing.
