Making biochar!

Timmo

Well-Known Member
I just made a great big batch of biochar. I haven't learned how to use it yet, but it was kind of fun to make, so I thought I'd share some pics.

IMG_150925.jpg


We had a willow tree fall down this winter, so I cut up a bunch of the branches and twigs and put them in a room with a dehumidifier.

IMG_161820.jpg


When they were all bone dry, I loaded them into my pyrolyzer (an old hot water heater tank).

IMG_161929.jpg


IMG_162025.jpg


I've never done this before, so I used a bunch of different sizes to see how they'd come out.

IMG_162126.jpg


Closed 'er up.

IMG_162222.jpg


Buried it in the middle of the burn pile I've been amassing for the last two years.

IMG_162728.jpg


Many hours later...

IMG_162822.jpg


The finished product (the next day).

IMG_163223.jpg


Everything looked exactly the same as when I put it in, only smaller and black.

IMG_163027.jpg


The burn pile itself also yielded a lot of biochar. There's at least another full garbage can's worth waiting for me to shovel it up.

IMG_163325.jpg


Grinding it up with a makeshift mortar and pestle. The twigs grind up instantly. The bigger chunks take a little more work, but it's not super hard. Powdering it exposes the most surface area, but I think I'll leave some chunky for aeration and use it in place of perlite in a future batch of soil.

Next time I do this, I think I'll separate the branches by size and do different batches. Twigs have the advantage of drying out very quickly and they can really be packed into the tank. I assume that charring them by themselves would also be faster.

IMG_163425.jpg


Voila.
 
Very nice showcase, I use bamboo biochar myself, which I later mix into soil.
 
You'd have to read the studies.
 
I don't want to look stupid but what is biochar
anyway? Isn't that what perlite and vermiculite
are? I have downed willows, I think I'm going to make a bunch of mulch with it...
I want to know more about this biochar stuff, what kind of benefits it has for plants....
 
There's another thread, just click back.
 
Franky, I'm not an expert, but here's the short answer to the best of my understanding: Biochar is a fancy name for charcoal that you add to the soil. It's just charcoal. Its main function in the soil is as a nutrient magnet; it has a very high cation exchange capacity, meaning that nutrients that become available but aren't used by the plants immediately can get grabbed by the biochar instead of just washing out of the soil. The plants can use the stored nutrients later when they need them. It's very porous, so if it's left chunky, it can also help aerate the soil.
 
What do U guys think about crushed lava rocks
mixed with soil...Is it any good? I was told that it has plenty of trace minerals, aerates soil and I think it does the same thing as biochar...
 
Sorry, I don't know anything about lava rock, other than I know people use it for aeration. If you google "lava rock cation exchange capacity," you can probably find out pretty quickly. Let us know what you find out--I'm curious.
 
Lava rock is different than biochar and it's used for mineralising the medium but it's very slow release so perfect outdoor or in indoor perpetual grows.
 
Oh okay, makes a lot of sense, thanks conradino23 for info...
What about the red wiggly worms they use to make worm castings, that's good to put on your soil, right? R ants really that bad?
Do plants still get some light if they R shaded by a tree part of the day? They don't get direct sunlight all day, do U think it will trigger them to flower too early?
Do they still get some light when it's cloudy?
Thanks, for all the info so far....
 
Worm castings are gold, and if you're growing in the ground, adding some worms can only help.

Ants are bad only because they like to bring aphids with them.

In direct sun, the plants actually get more light than they need. They get plenty when it's cloudy, and shaded part of the day is fine too. If they're shaded in the late afternoon, that can actually be a plus. Neither cloudy nor partial shade should trigger flowering.
 
Given that ashes are quite alkaline and can have a fairly strong effect on raising the ph of the soil, are there any issues around Ph when using biochar?
 
Not that I've noticed in healthy plants brought up my way.
 
Weaselcracker, I did a little research and also tested my biochar. Indeed, it is pretty alkaline. Apparently, the hotter the burn, the higher the pH of the resulting charcoal. I tested mine by mixing 1 part char with 2 parts RO water, letting it sit for a few hours, pouring it through a coffee filter and pHing the liquid. My RO water, for some reason, started at 6.5. I tested three different batches of biochar that I've made using two different methods, and they all came out between 9.1 and 9.4 pH. Since the RO water wasn't neutral, I assume the actual pH is a tad higher than what I measured, but not much.

At the same time, I tested the pH of my native soil, which I haven't limed this year yet. It came out at 5.5 pH. Given that the biochar will probably make up only 3 to 5 percent of my mix, and my native soil will be around 30 percent, I don't foresee any problems.

Thanks for bringing up the issue, though. I hadn't thought about the pH of biochar at all.
 
Back
Top Bottom