BioChar

[crucialbunny]

There's been a lot of talk in the gardening communities recently about the benefits of using biochar as a natural amendment to their soils. Anyone here have any experience using it for their grows?

[Bluey]

Yes, if your biochar definition is raising the temps of the biomass well above that needed for decomposition. But I do not allow all the water to escape from the mass.

I keep adding water and oxygen by mixing it so I stop and restart the anaerobic process a dozen times or so. I reseal the mass so it goes anaerobic.

I don't let it get to the point where it all dries out. Only the centre of the mass dries out and gives the appearance of having been burnt or charred.

It can get quite hot in the centre and if you allow it to fully dry you risk fire and it will also stop the decomposition process occurring on the outer of the mass.

So what I end up with is a mix of biochar and fully composted organic matter.

[SoOrbudgal]

I have not used it but have put wood ash in my veggie beds which does have small quarter size pieces of burnt wood.

[Bluey]

I add a bit of ash also to the mix.

[Gingerbeard]

Biochar=charcoal. Yeah. It's good for plants.

[Rwise]

Come on down and cut ya a truck load!

[Orggrwr]

Don't forget to shoot the endangered owls living there while you're at it

[Rwise]

The owls are over in the valley, though a few tree rats may be out of a home.

[crucialbunny]

Well, I pulled the trigger and ordered 3 one gallon bags of the stuff. I think what I'll do is use it with half my grow and see if there is any noticeable difference.

[Gingerbeard]

There might be a difference between hardwood ash and softwood ash.

[crucialbunny]

I make my own living soil. I've had a 35 gal worm compost bin going for about 5-6 years that provides plenty of castings for my container gardening needs. I typically I add kelp, worm castings, fresh compost, ground oyster shell, sand, horticultural Epsom, and freeze dried minnows to the previous year's soil and let it develop for a couple months under leaf litter to bring the PH into balance. My home is in a somewhat urban area so cooking my own biochar isn't really an option. The stuff I ordered is primarily pecan and pistachio shell with added mycorrhizal fungi. My plan is to only use about 5-7% in 30 gal bags.

[Rwise]

Compared to softwood ashes, hardwood ashes contain higher percentages of nutrients and have more of a liming effect on soil. Although hardwood ash is only about half as effective as lime for raising soil pH, it should still be used with caution.

I use both in my gardens, whichever I have is fine.

[Orggrwr]

Read up on this a couple years ago. Biochar is not ash. It's made by cooking wood at high temps in a no oxygen environment so there is no flame. Everything but the basic cellulose structure of the cells are turned to vapor. This leaves lots of nooks, and tunnels that allows it to absorb and hold water and nutrients for slow release as well as giving beneficial microbes a place to hide and ride out drought etc. ( the book I read claims that because of all the microscopic holes a piece of biochar the size of a grain of rice has the surface area of a football field) Holy Shit! But because it absorbs a lot of stuff when fresh it can actually cause nutrient deficiency at first. To use in pots it must be "charged" first by mixing with compost or some kind of nutrient source for a couple of months. ( biochar itself has no nutrients). For these reasons it's mostly beneficial for outside gardens and raised beds. I mix a little into my compost pile while its cooking so it ends up in my pots with the compost. Haven't really noticed any kind of drastic improvement in my plants since I've been using it but something like that is hard to quantify and its easy to throw a few handfuls in the compost pile every now and then so why not. My plants haven't complained. Also once it's in the soil it lasts basically forever.

[Bluey]

My understanding of biochar is that it can contain any organic matter, not just wood/grass/cellulose and that it doesn't have to be cooked to such an extent that the entire mix becomes like charcoal. For that to happen you'd need complete removal of moisture and quite high temps when making it and I couldn't maintain those temps and at the same time keep the process anaerobic.

Adding organic matter such as manure (including treated and untreated human waste), blood and bone, etc, adds nutrients that we want in our soils and increases biological processes in the mix/soil it is added to, if moisture levels are maintained and it is not cooked to such a temperature to kill off the micro organisms.

The process I used kills worms. It gets too hot for them but it accelerates the breakdown of the organic mix into a rich soil if moisture levels are maintained. It can then be mixed into the soil or added as a spreader and watered in.

My rationale behind mixing this and adding water every time it dried out too much was to maintain a high level of active and living micro organisms that I needed in my soil as the natural soils around my place were crap, lifeless and low on goodies (nutes) because of lack of microbial activity.

It can also help increase CO² levels in a farmers pasture and help act as a carbon sink. High levels of CO² in soils is conducive to healthy soil increasing yields.

So perhaps the end result is not biochar but a type of compost made with much higher temps than needed for regular decomposition. If it is allowed to dry out through you do end up with very light weight chunks of organic material but not totally black and burnt.

[Gingerbeard]

This thread was the first place I saw the word biochar.
This article was the second.
The 'dark earth' revealing the Amazon's secrets (bbc.com)

[crucialbunny]

Great article. Thanks for sharing. Reinforces my belief that the old natural ways are worth keeping alive.

[Orggrwr]

That reminds me I found my source for the info I posted above. "Biochar for Home Gardeners" by Jeff Fry. A good read for anyone interested in starting and/or maintaining an organic no-till garden. Jeff Lowenfels has a series of books" Teaming with Nutrients , Teaming with Microbes" and several others that are great reads for anyone interested in the nuts and bolts of what's going on inside your plants. They are not cannabis specific but very informative about how plants do what they do