Bio Char in the garden

[junksta]

I've always used a little ash in the garden, but there is an interesting article in Mother Earth (Feb/Mar), about adding charcoal or, bio char as they call it. Seems lots of beneficial organism like to cling to the bio char. With our horrific soil, I through everyting at it, now I've started a bio char bucket beside the stove.

 

[Gooserider]

I will admit that I tend to take stuff that I see in TMEN with a large grain of salt until / unless I see independent confirmation elsewhere, but it sounds reasonable. I have never made a special bucket for it though, as I am not going to pull extra coals out of my stove when they could be making heat... Instead I have my two galvie garbage cans that I dump my ashes into all winter, along with whatever small bits of charcoal fall through the grate. I spread this over the garden in the spring, along with a good bit of compost, and the occasional load of "llamadoo" from my beekeeping supply lady, who likes to give her customers chit - it saves her from having to get rid of it in other ways...

Gooserider

 

[Beanscoot]

There was a good story about this on the CBC (Canadian Broadcasting Corporation-similar to the US NPR) science show a few months ago.
They were talking about this "biochar" used in South America centuries ago. The biochar wasn't really charcoal, it was half burnt garbage, like chicken bones and food wastes. This would contain a fair bit of phosphorus and nitrogen, which will be absent from true charcoal. I've often wondered about the harm or help that charcoal would give to soil, as it will be activated charcoal and possibly absorb nutrients and not let them go. Or else hold them for the plant roots to take up.

I am pretty meticulous about separating out all the bits of charcoal from my ashes, and I mix it into the compost with grass clippings and food waste.

 

[jebatty]

Adding char is good for the garden - char = carbon, essential for all living things. I save some unburned coals from the wood stove, crush them, spread over the garden, and lightly rake as a top dressing along with compost. Great garden. No fertilizers.

 

[Beanscoot]

When I was a teenager I had a friend whose mother occasionally burnt food pretty badly. When he complained, she told him, "Eat it, carbon is a building block of life!"

But the problem with carbon is that it's not digestible in elemental form to many organisms. Plants do not get carbon from this or any other organic matter in soil. They get their carbon through photosynthesis, i.e. from carbon dioxide in the atmosphere.

 

[jebatty]

The carbon as char has many apparent soil benefits, such as increasing moisture retention by absorbing and holding water, reducing erosion, may capture other gases from the atmosphere and facilitate other chemical reactions which result in nutrient addition, loosens the soil and promotes deeper root penetration, enhances root hair formation and plant growth, and research continues. Plus, carbon stored in the soil doesn't end up in the atmosphere.