When you look at gardening podcasts on YouTube, you'll be presented with a host of things that are heralded as the only thing you have to do - or add - to fix whatever problem you might be having with your garden. In truth, success probably has more to do with a host of little things.
Biochar is one of these. It's easiest to understand if you don't think of it as a scientific product but as a type of charcoal that can improve your soil.
Biochar is charcoal specifically made for soil. It is created by heating plant material (wood chips, crop residues, nutshells, and even weeds) in a low-oxygen environment. This drives off oils and gases and leaves behind a lightweight, carbon-rich skeleton. Larger pieces of wood can work as well, since the uncharcoaled portions will break down into forms that benefit the soil.
In biochar, the skeleton that it leaves behind is the key, however. When viewed under a microscope, biochar would look like a sponge with tiny tunnels and chambers. When added to your compost or soil, these spaces will hold water, nutrients, and microbes.
Biochar doesn't feed plants in the way that fertilizer does. Rather, it changes the soil's composition. Biochar holds water like a dry sponge suddenly dipped into a bucket. It stores nutrients so they aren't washed away by the next rain. They shelter microbes, the beneficial ones that break down organic matter and help roots. They buffer pH gently, especially in acidic soils. And they lock carbon away for centuries rather than letting it return to the atmosphere. It is less a nutrient source as it is a soil architect, creating structure and stability, setting the stage for long-term fertility, unlike fertilizers that may be used up in one growing season.
Because biochar is porous, it has a huge internal surface area, as much as hundreds of square meters per gram. This is why it can hold so much water and house so many beneficial microbes.
Biochar's surface chemistry allows nutrients to cling to the char rather than leaching away. Stability stems from the fact that it doesn't break down quickly but remains in the soil for decades, or even centuries.
When mixed with compost or soil, biochar becomes a kind of living habitat. It is colonized by microbes, explored by roots, and through which water can move slowly and predictably.
While adding biochar directly to your garden soil will improve the soil over time, it might harm the soil in the short term by making nutrients unavailable to your crops. The long-term benefits will be good, however.
The better idea is to add it to your compost before adding it to your soil, allowing it to be pre-charged. If buying biochar, it is available pre-charged. Otherwise, give it a chance to become inhabited by beneficial nutrients and microbes.
The terms "charging" and "innoculating" are described in the video.
Not only does biochar contain nutrients that are directly beneficial to the soil, but it also contains the microbes that worms eat, thus attracting worms that will further benefit the soil.
Like pretty much everything else you might see on YouTube, it won't solve all of your problems, but it can help.
Biochar is one of these. It's easiest to understand if you don't think of it as a scientific product but as a type of charcoal that can improve your soil.
Biochar is charcoal specifically made for soil. It is created by heating plant material (wood chips, crop residues, nutshells, and even weeds) in a low-oxygen environment. This drives off oils and gases and leaves behind a lightweight, carbon-rich skeleton. Larger pieces of wood can work as well, since the uncharcoaled portions will break down into forms that benefit the soil.
In biochar, the skeleton that it leaves behind is the key, however. When viewed under a microscope, biochar would look like a sponge with tiny tunnels and chambers. When added to your compost or soil, these spaces will hold water, nutrients, and microbes.
Biochar doesn't feed plants in the way that fertilizer does. Rather, it changes the soil's composition. Biochar holds water like a dry sponge suddenly dipped into a bucket. It stores nutrients so they aren't washed away by the next rain. They shelter microbes, the beneficial ones that break down organic matter and help roots. They buffer pH gently, especially in acidic soils. And they lock carbon away for centuries rather than letting it return to the atmosphere. It is less a nutrient source as it is a soil architect, creating structure and stability, setting the stage for long-term fertility, unlike fertilizers that may be used up in one growing season.
Because biochar is porous, it has a huge internal surface area, as much as hundreds of square meters per gram. This is why it can hold so much water and house so many beneficial microbes.
Biochar's surface chemistry allows nutrients to cling to the char rather than leaching away. Stability stems from the fact that it doesn't break down quickly but remains in the soil for decades, or even centuries.
When mixed with compost or soil, biochar becomes a kind of living habitat. It is colonized by microbes, explored by roots, and through which water can move slowly and predictably.
While adding biochar directly to your garden soil will improve the soil over time, it might harm the soil in the short term by making nutrients unavailable to your crops. The long-term benefits will be good, however.
The better idea is to add it to your compost before adding it to your soil, allowing it to be pre-charged. If buying biochar, it is available pre-charged. Otherwise, give it a chance to become inhabited by beneficial nutrients and microbes.
The terms "charging" and "innoculating" are described in the video.
Not only does biochar contain nutrients that are directly beneficial to the soil, but it also contains the microbes that worms eat, thus attracting worms that will further benefit the soil.
Like pretty much everything else you might see on YouTube, it won't solve all of your problems, but it can help.
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