Photograph via snooOG

For articles & discussions relating to biochar and its many benefits.

The Biochar Reddit

Biochar - charcoal used as a soil amendment. Biochar is a stable solid, rich in carbon, and can endure in soil for thousands of years. Like most charcoal, biochar is made from biomass via pyrolysis. Biochar is under investigation as an approach to carbon sequestration. Biochar thus has the potential to help mitigate climate change via carbon sequestration. Independently, biochar can increase soil fertility of acidic soils (low pH soils), increase agricultural productivity, and provide protection against some foliar and soil-borne diseases.

Wikipedia: Biochar

Terra preta - a type of very dark, fertile manmade (anthropogenic) soil found in the Amazon Basin. It is also known as "Amazonian dark earth" or "Indian black earth". In Portuguese its full name is terra preta do índio or terra preta de índio ("black soil of the Indian", "Indians' black earth"). Terra mulata ("mulatto earth") is lighter or brownish in color.

Terra preta owes its characteristic black color to its weathered charcoal content, and was made by adding a mixture of charcoal, bone, and manure to the otherwise relatively infertile Amazonian soil. A product of indigenous soil management and slash-and-char agriculture, the charcoal is very stable and remains in the soil for thousands of years, binding and retaining minerals and nutrients.

Wikipedia: terra preta

Slash-and-char - an alternative to slash-and-burn that has a lesser effect on the environment. It is the practice of charring the biomass resulting from the slashing, instead of burning it as in the slash-and-burn practice. The resulting residue matter charcoal can be utilized as biochar to improve the soil fertility.

Wikipedia: slash-and-char

Also see /r/BiocharVideos for videos on biochar

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Important article(s)

Rice U scientists: Cooking temperature determines whether 'biochar' is boon or bane to soil


3,849 Subscribers


Does paint need to be removed from a ring kiln?

I'm considering converting an old propane tank into a ring kiln. In the link below with instructions on how to do this, they mention to sand blast the paint of the tank. I'm curious if that is really necessary or not. I'm guessing it probably is because the metal will get so hot from the fire it would cause an issue with the paint?


23:02 UTC


First ever batch

I just made this rinsed it over a screen and once it dries I’ll hand grind it. Just twigs and stuff from the yard. I’m hoping to add it to some potted plants. What do you all think?

19:09 UTC


Human consumption ?

I have read about benefits of bio char for livestock but can it be consumed by humans and if so for what benefits and how much quantity wise? TIA

05:53 UTC


Just tried two systems from other YouTube videos.

1 Comment
21:58 UTC


Lowering biochar ph

I read that most biochar have an alkaline ph. However, we already have really alkaline soil which is rich in lime and clay. How can I lower the ph of my biochar to make it usable for my local alkaline soil?

11:18 UTC


Can I activate biochar with left over liquid fertilizer? Looking for a way to use it as I am not sure how to dispose of it.

07:52 UTC


Making biochar in a single drum

Hi. I’m wondering whether it is possible to make biochar in a single drum, without using methods like double drum. I have limited land and limited budget.

12:47 UTC


Commercial Applications of Biochar?

Hey there!

I’m interested in learning if Biochar is used at a commercial, or large-scale anywhere around the world, in any industry? It seems like an amazing resource that can be created readily, but the adoption seems to be limited to small garden-holders.

Any idea if it is being used in large-scale agriculture, cement, water filtration etc.? Or are these all theoretical applications, proven only in studies but with no use-case in commercial situations?

I’d love to hear if anyone’s had any experience or knowledge about this!

17:55 UTC


Green Carbon Webinar

Hello there,

Does anyone follow the green carbon webinar?

Next session this Thursday 2nd November, focused on CDR policy in the US and Europe, featuring:

- Sebastian Manhart (carbonfuture) talking about the rapidly changing CDR policy in the US and Europe

-@Alaa Salma (UniLaSalle) will give a presentation about biochar integration into anaerobic digestion

Registration at www.greencarbonwebinar.org


1 Comment
17:28 UTC


Won't producing biochar produce carbon monoxide?

I remember reading that carbon monoxide was produced in absence of oxygen.

21:17 UTC


Does charged biochar get "washed out" if I spread it before winter?

I've got a few buckets of charged biochar that prefer not to store over winter, so I was thinking about mixing it with some soil and compost and spreading it in my flower beds in the coming weeks.

The question is whether a few months of rain and snow will "discharge" the biochar and wash out the nutrients, or if it should be fine to do things this way.

08:30 UTC


Soil improvement using biochar, area 2'x5'. How do I amend?

1 Comment
03:55 UTC


Where can one buy a few yards of biochar near south Cook County, IL?

Innoculated or raw.

12:17 UTC


Parabolic solar ovens for making small batches of biochar?

Has anyone played with parabolic solar ovens for making small batches?

I've been reading about parabolic solar ovens, but nothing I've read talks about the power output so I can't tell if they could make, say, a soup can of wood chips or acorns hot enough to undergo pyrolysis in an afternoon.

13:15 UTC


Commercial production

Looking to potentially add biochar production as a component to an urban sawmill/tree debris processing operation. Locally a huge amount is chipped and shipped to steam boilers and biomass plants. Would love to find more info in terms of production metrics and markets. Would love to hear about any experiences with permitting. I have no experience so anything is helpful.

01:56 UTC


After soaking my charcoal and making biochar, what can I do with all the leftover liquid?

16:37 UTC


Gaskets from maple syrup evaporators to seal biochar retort

I am interested in ways to turn any vessel into a Hookway retort, to make scaling beyond a 55 gallon drum easier. One idea I had was to cut the upper section of the vessel off, and weld a collar around the inside of the bottom portion that the top could then just slide over to close things up. But I assume I would need some kind of high temperature seal or gasket around the collar to keep the pyrolysis gases from leaking out, and I was thinking that the webbed rail gaskets that they use for maple syrup evaporators might work. Any thoughts?

09:51 UTC


Mint: not scientific. propagated in water, planted about 2 weeks ago in roughly the same length, root mass and condition. Approx same water and same position with currently 8+ hours sun. One is my previously completed batch of compost, the other is my compost + charcoal inoculated 2+ months

00:34 UTC


Live streaming now: Oct 4, NASEM Wildfire Risk Reduction, Carbon Dioxide Removal, and Biochar: The Challenges of Scaling Up

Sharing this live streaming event on biochar that started a few minutes ago.

Oct 4, NASEM Wildfire Risk Reduction, Carbon Dioxide Removal, and Biochar: The Challenges of Scaling Up

No registration required.

Please join the National Academies for a special public session to explore

Key Themes: 1. Quantitative estimates of the volume of new wood biomass generated by forest restoration initiatives 2. Options for utilization of noncommercial wood biomass; carbon profiles and implications 3. Current and potential utilization and markets for biochar 4. Status and trends in US wood biochar production: case studies 5. Biochar and CDR credits 6. Research needs 7. Policy implications

1 Comment
15:26 UTC


Some of my methods for making and processing char

I just wanted to share my biochar experiences so far. Sorry I don't have any relevant images. I have 2 effective ways of burning/processing and some advice on mixing it into final form.

Method 1:

I drilled 8 holes at the bottom of a metal 50 gallon drum about 2" up from the bottom. The holes are 1 1/2" diameter. I put 4 bricks in the bottom and an old grate from a weber grill to make an air space. This creates a pretty oxygen starved burn, especially when you burn down brush about 6-8" high. I am usually burning long branches so I fill the drum vertically until its packed. I use a garden hose to keep the flame down during the entire burn. I usually burn from a 10x10' pile of branches. Using the hose to keep the burn smoky causes alot of charcoal to form and very little ash. In about 4 hours I can fill the drum to the top with charcoal.

Method 2:

This is a bit more dangerous because I burn in a forest. I cover a brush pile with a tarp and let it dry out. I clear a 20' diameter burn ring scalping the earth with a string trimmer. I wait until it has rained a few days and when it stops I uncover the pile and burn it. I use a garden hose and try to put out the fire for the entire burn, which with a 5/8" garden hose is impossible, you can dampen the flames but the coal will keep burning the wood and its a very smokey procedure. I can burn a 10x10' pile in about an hour this way. The garden hose washes away the majority of the ash so I am left with a massive pile of charcoal.


I like to process different sized particles. I usually fill a lawn mower dump cart with biochar and take it up to my garage to process it. I will take a plastic mortar mixing bin which I think is 20 gallons and I fill it 1/4 with tap water and then I add some chlorine neutralizer used for fish tanks. I then add a 1/4 cup of blood meal, a half cup of bone meal, 1/4 cup of fish emulsion, and then stir it up. I also add 1 tsp of mycorrhizae and 1 tsp of a dedicated soil bacteria. Finally I throw in a tsp of granular molasses. Finally I add my biochar chunks and fill the bin half way. I like to stir them around in the mix and let them sit for a few hours and then I use an 8x8 tamper from harbor freight to smash the char into oblivion. The liquid mixture helps keep the dust in check. Finally I let the mix dry on a stainless window screen that sits on an old wood pallet.

My other method involves using a $5 blender from walgreens. I use this for house plants because I like to pulverize the char into the finest powder form possible. My house plants are mostly ornamental aside form a lemon tree and a lime tree. I use an organic granular citrus fertilizer made by microlife and put a half cup in with about 2 cups of char. I then add water form my reverse osmosis filter and make a thick jet black biochar milk shake. I let this sit for a day and give 1/4 of this concentration to each plant in my house by diluting it into a watering can, also filled with RO water.

This has been really effective for me in the last year. I recently bought a compost spreading drum for my lawn and plan to start doing biochar on the lawn, I have so much I dont want any to go to waste. My neighbor now has chickens and is willing to share their waste, I personally compost grass clippings, wood mulch, and leaves, so in the future I am hoping to add a worm bin and stop buying fertilizer, or at least minimize purchases to bone meal.

btw: There is a person on here growing cactus in pure biochar, I am very inspired by this. I want to try and make a growing medium mix now and see if I can pull that off.

18:05 UTC


Just added it to soil

I just put my mixture to the soil after 3 days of letting it innoculate . I tilled it in to the land

13:24 UTC


Biochar made

So today I went to the farm and made the biochar and I’ve let it settle for three days to charge , I mixed manure from my biogas set up with some kitchen waste , charcoal and eggshells . Will keep the community updated on every step . I am excited to share with you guys my progress and any tips shared would be nice (:

14:41 UTC

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