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Anyone use/make biochar?

I've been reading about it lately, also called terra preta, and was wondering if anyone has any experience with it?  As an experiment I've crushed charcoal and added it to the coco coir.  At the very least it'll help sweeten the soil, hopefully it'll also be a medium for microbes to thrive on and increase the biological activity, reducing nutrient needs.
 
I'd love to hear from anyone who has experience using it, either indoors or out, as I'll be incorporating it into my outdoor garden next year.
 
The bagged compost that I used in my containers this year had biochar in it.  I really can't speak of its benefits though, as I've had a tough go around this season.  But I can't blame that on the biochar, but rather my own stupid mistakes.
 
When I was researching it I think I remeber something about how its not just any old char you want... there are particular types of wood and firing processes involved in making really good bio-char for terra preta... like it has to be very slowly smoldered... or something like that.

I know you can definitely over-do it... and especially with wood ashe as a liming agent... its more potent than you may think. (I have learned that the hard way XD        ... Derp)

Also.. I know that the practice of 'constructing' terra preta is great for the management of greenhouse gasses... as it locks up the carbon in the soil ;)
 
I use all the lump pieces left over from grilling.  I use 100% lump so no additives and I break it up before adding it in.  It is noticeable in the different containers that do and do not have it. 
 
I'm sure there's a big difference in quality depending on how the charcoal is produced, that being said from my understanding the biggest direct effect it has on soil health is creating a place for microbes to thrive because of the irregular surface area/porous nature.  Which would be effected by the wood's density, how it was burned, etc.  I'm going to try the traditional method of piling the left over biomass into a pit dug in my beds with some wood, burn then cover with soil for next year, but for now charcoal (natural with no additives) was the best I could do in a pinch as my indoor garden should have been transplanted a week ago.  I hadn't come across any info on wood type effecting it though, that's good to know as I'll be sure to use both hard and soft woods.
 
Good to hear you're seeing a difference Millworkman, saves me the mental argument of adding it to all the plants or just some.  One less voice in my head is always a good thing...
 
I made a butt load of char for my garden after reading an article in National Geographic a few years back. I made a charcoal kiln out of 1/4" plate and an old 2' diameter firebox. Put the char in buckets and let it soak, then placed it in pillow cases and ran it over with the truck. I put down 3"s in 2/3 of the 48x67' garden and tilled it in. Did a test the first year and corn grown in and out had a 12 to18" height difference, had to fertilize and water the shorter corn twice as much.
 
I'd say it's helping..
 
Monkey Hunter said:
from my understanding the biggest direct effect it has on soil health is creating a place for microbes to thrive because of the irregular surface area/porous nature. 
 
True... It does have that physical property.. but it also has the chemical properties that sequester nutrients in the soil (literally grabbing them and holding on)... so that the ions your plants and beneficial microbes want dont wash into the river every time it rains!!!!!
 
What material did you use Drew?  Good to hear more positive reinforcement, with the carbon sequestering I'm slowly convincing my Dad to build a biochar burner to heat their chicken coop this winter.
 
I wasn't thinking about the cation exchange capacity, now I'll have to see what I can learn as to whether that's from specific physical/chemical property or if it's simply what charcoal does regardless.  I don't suppose you have any links from when you were researching it?  I figure it's a long shot but if I remember (which rarely happens) I dumb useful info/links into a folder for future reference, on the off chance someone else is as nerdy/obsessed as I am around gardening I figured I'd try...
 
Monkey Hunter said:
What material did you use Drew?  Good to hear more positive reinforcement, with the carbon sequestering I'm slowly convincing my Dad to build a biochar burner to heat their chicken coop this winter.
 
I wasn't thinking about the cation exchange capacity, now I'll have to see what I can learn as to whether that's from specific physical/chemical property or if it's simply what charcoal does regardless.  I don't suppose you have any links from when you were researching it?  I figure it's a long shot but if I remember (which rarely happens) I dumb useful info/links into a folder for future reference, on the off chance someone else is as nerdy/obsessed as I am around gardening I figured I'd try...
Meaning what did I make the char out of? I used Mequite. I read up on this 4 or 5 years ago, so I don't remember the resources. What intrigued me was in the Amazon jungle they found the bio char (Terra Preta) and farmers were growing on it for many years without having to add nutrients. So one of the characteristics is the ability to capture and store nutes. I suggest reading up on Terra Preta, Bio Char searches are mostly $$$$ sites.
 
Back when I did the research I found some interesting info about creating bio char as an end result of using chicken manure for fuel to heat the houses. It was being sold for a lot higher price than the manure sold for. It was even sponsored by the Feds...
 
This was what got me looking into it, http://www.cultureunplugged.com/documentary/watch-online/play/12245/The-Promise-of-Biochar, (11 minutes from cornell university) as before I watched most sites/references where all about the $$$.  They mention a farmer who's using chicken manure to make biochar, he use to sell manure for 6$ a ton, now he sells biochar for 600 a ton...
 
Like you said though, it's the longevity of it's action that impresses me, definitely worth looking at.  I also realized that if you're making it in beds, it'd decontaminate the soil of pathogens as well as building it up.
 
Yet another absolutely simple, low tech inexpensive, ancient technique that we're only now understanding the science behind and realizing how much more efficient  is to work with nature instead of against...
 
I seemed to have missed the details of this one. Great info, thank you for passing it along.
 
Got some nice crabapple and mulberry wood* waiting to do the job :)
 
Pretty coincidental you started this topic after I was reading a new book I got and was going to post about the info of biochar in it. So I will just post it in here. This information is from "the minifarming guide to compost".

Biochar is a benign soil amendment that enhances the value derived from compost added to your garden. The earliest known use of charcoal as a soil amendment was by the people who inhabited the amazon prior to the arrival of Columbus. They made their biochar by setting their agricultural waste ablaze in trenches and covering it with earth to smolder. Explorers called the dark carbaceous earth resulting from this terra preta. Charcoal is insoluble in water and stable. It has a tremendous unfolded surface area that can provide a home for soil bacteria , help absorb water, and help hold nutrients so they don't wash out of the soil. It can bind with humid substances thereby Improving soil consistency while reducing the rate at which organic matter is depleted from the soil. The benefit of biochar increases with age and even the addition of as little as one pound per 100 square feet of garden will yield benefits. There are no existing guidelines for adding a specific amount of biochar to soil based on type or crops grown. In tests of soil with little biological activity excess amounts (20 lbs or more per 100 sq ft) can make nutrients less available the year applied. However through subsequent years they will be released and the effects reduced. Because biochar accumulates you should keep track of the total amount added in a gardening log. Once your total additions equal 10 lbs per 100 sq ft there is no need to add more. From testing there are no added benefits to an excess of 10lbs per 100 sq ft after five years.

If making and adding your biochar it is recommended to add it to equal parts compost and let it sit for a week to a month before adding to the garden.

A good source is pure hardwood charcoal for the grill that has no additives to it or as others have described above making it yourself from scrap wood around the yard.

I fully intend to use this in my soil for next year.
 
I plan on using biochar before next season to try and get a terra preta thing going, especially since my plants this year seemed to have excess nutrients followed by defiencies after massive amounts of rain.

I'm just going to use the black charcoal pieces left behind after my yard refuse wood fire. Not making a kiln or anything since those blackened wood pieces will have undergone pyrolysis and you don't need to add much char per year since its culmulative.

Also should help improve my nearly topsoil-less, compacted clay soil structure. Gonna amend the heck out of it with compost, biochar (idk why they call it this, its just charcoal), manure and more.
 
Biochar sounds more dynamic and exciting, plus it's hard to sell charcoal at the same inflated prices ;)

Great info CS, good to know there's no benefit after 10lbs/100sq.  Thanks for posting the link Noah, unfortunately my comp battery is about to die so I'll have to check it out tomorrow
 
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