How long do you inoculate your biochar for?

I have seen different recommendations.  I am not a Phd or an owner of a commercial biochar enterprise, so I ask others about this.  I just make it for my yard.  

I crush mine first in the driveway for a week.  After that week, I inoculate it for two weeks. I drench it once a day with a mixture of urine, whole wheat flour, ag lime, sea weed, rotten wood mycelium, rotten fruit, regular compost and worm compost.   I notice that during the first week, a lot more of that liquid goes in and goes out during the daily drench.  This seems to be telling me that during the second week, the biochar has largely filled in the microbe hotels and it is ready to be put out into the garden.  Biochar is pretty new as a regular practice for most of the people in Western societies.  I want to learn from others.

What do you do?

John S
PDX OR

I, uh.... crush mine with some rocks and then mix it straight into the compost.
As the compost breaks down, the biochar sucks up as much as it can.
By the time the compost is finished, I assume the biochar is maxed out.

Stuff I put in compost includes:
Green & Brown plant material, especially dry hay & grass clippings, rotting fruit, any small animal bodies (Neighborhood cat likes to leave half-a-mouse/rabbit presents on our porch), urine, shredded paper & cardboard, woodchips, a couple shovelfulls of dirt every once in a while, campfire ash & crushed charcoal for 'biochar.'

I'm afraid I don't buy off-site fertilizer or specific amendments like seaweed or worm castings. The only thing I get off-site is woodchips from a local tree-trimming company who dumps it in my yard for free.

Worm castings are being generated in the compost pile by local worms, and any bones/blood from the bodies end up integrated on its own.

Adding charcoal into the finished compost/humus seems to make it 'last longer' than no-charcoal: that is, the fertilizing effect of a humus application appears to persist for a longer period of time.

I do the same as Toko.  I mix mine into my compost piles as I am making them and let it be inoculated as the compost breaks down.  I have an area that I am making some new beds this year.  The first year I make new beds in unaltered area, I sometimes till.  I'm going to till plain charcoal into some of the beds to help break up the heavy clay.  After that, I am going to cover the areas with heavy tarps and leave them all year to kill all the weeds.  I won't be planting these new beds until next year, I'll see what effect the charcoal that hasn't been inoculated will having on my plant growth.

I soak mine in compost tea and usually some nitrogen source for 2+ weeks.

I think that one of the strengths of permies.com is that we can all share what works for us.  Especially if you have some similarities to other people's set ups, you can adapt successful protocols to your own place, whether you are on a huge rural farm, smaller homestead, suburban lot, or in the city. It wasn't until I saw a method for making biochar that I realized I could reasonably do, that I actually started making it. I had been planning to figure out how to make biochar for years.

JohN S
PDX OR

John Suavecito wrote:I think that one of the strengths of permies.com is that we can all share what works for us.  Especially if you have some similarities to other people's set ups, you can adapt successful protocols to your own place, whether you are on a huge rural farm, smaller homestead, suburban lot, or in the city. It wasn't until I saw a method for making biochar that I realized I could reasonably do, that I actually started making it. I had been planning to figure out how to make biochar for years.

JohN S
PDX OR

I think that your way of inoculating charcoal works better than my way, and there are times when having mine inoculated more quickly would be very helpful.  I just have so many things going on all the time that I have to try to find a nice compromise between not doing something, and doing it as well as possible.  Many of my projects, like this, end up somewhere around "good enough".  Critical things like animal housing or the like, I work much more towards as perfect as I can get.

We are on the same page with simply making biochar.  I put off even trying for a long time because I wasn't sure I could do it correctly, or what method was "best".  I researched and researched until one day I just tried it.  Lo and behold, it's a really simple process and "best" is different for different people and their personalities and situations.  Now I just hope everyone will try it :)

I agree wholeheartedly that one of the strengths of this community is the ability to look at what other people in a similar situation, and even very different situations, are doing that works.  It gives me the confidence to try things I otherwise wouldn't.

I think an interesting notion of charcoal and ash, is that the substance itself, holds less water in drought, then surrounding soil. Trees often die in pure ash, due to not enough moisture. This notion makes sense, as dry fire residual, is lower pressure dry then when wet. This increase in low pressure, though does not hold more water in itself, but instead in the surrounding soil, making more water available relatively. Therefore you do not necessarily need to use it specifically, will effect a large area outside where used. My simple method of making bio-char is simply, putting the fire out at the right time, I’ve tried fire covered with soil, makes a lot of fired soil, but little charcoal. Easier and simpler this way. I’ve urinated on ash for months using it as supplement for garden. Now a days I make mass burials, never using it on garden itself. Have been really pleased with my corn crop, without any fertilizer or composts, has grown remarkably well, 4-5 ft tall now and dark green. Better then last year also without fertilizer. To rephrase the question, I inoculate bio-char while burning to make it. Feces, collect and re burning chicken coop floor materials, urine, save tobacco bong spit to extinguish, old food, animal food, burn all hair keep all hair short for this purpose. A good purchase would be scratch feed, to simply burn while making it.

Trace and Adam,
That's exactly what I'm talking about. You are adding different viewpoints and highlighting slightly different situations and methods to deal with them.  I remember before I had my food forest, how farmers would say that you are never going to get everything done.  And you certainly won't get it done as well as you'd like.  But if you just keep waiting for 10 years before starting, that is 10 wasted years when you could have been improving your soil food web.  You can start in a way that you can envision yourself doing it and just keep improving over time, by listening to others' experiences.   Adam, your method sounds similar to the original biochar in Terra Preta, Brazil.

John S
PDX OR

John Suavecito wrote:I remember before I had my food forest, how farmers would say that you are never going to get everything done.  And you certainly won't get it done as well as you'd like.  But if you just keep waiting for 10 years before starting, that is 10 wasted years when you could have been improving your soil food web.  

John S
PDX OR

That's exactly right. Not to mention, I never want to be "done".

Last year, I incorporated a lot more char into my composting operation. It was the easy way to inoculate it.

It was also a drought year, so I cut a free IBC tote liner in half (vertically) to make compost bins that I could keep damp. I was surprised at how much stinky leachate even a small rain shower would produce -- enough that it could turn the pile anaerobic, so I had to dip it out and put it on the drip line of trees. But I saw it as a resource, even though it was too stinky to use in the garden proper.

This year, I'm burning a lot of brush, which produces large volumes of crude char. So in addition to adding to compost, I'm capturing the excess leachate and using it to inoculate 80 litre garbage bins of crude char (along with a few shovels of municipal compost). The stinky smell was gone in a day. I'm not sure it's perfect as an inoculant, but it's a good experiment. I suspect it's a lot better than spreading raw char.

A lot of you that have acreage and use the trench method can make way, way more biochar than I can. It is definitely an advantage to those kind of systems. I don't have acreage, so it isn't optimal for my yard.  It helps the planet a lot more than my system too.
JohN S
PDX OR

At a certain point, excess brush is more of a PITA than a resource, unless you have a big chipper. I'm trying to remove the fire load on my hills, clearing out the deadfall and standing dead trees. It would be a lot easier to burn it down to ash, but I suppose I'm creating a partial carbon offset for a short plane trip I need to do this year.

I am a bit of a newbie to the inoculation process but I'm going with the 14 day method with a wet soak approach.

Its like a big ole gross soup. I love it, mix it once a day at least.

Starting this year, I have adapted my inoculation process to the liquid mix drench for one week.  The extra week didn't seem to make much difference in the biochar, and it was a lot more work for me.

John S
PDX OR

Thanks all for sharing your methods. I am about two days in with soaking my crushed char in a fresh batch of aerated compost tea in a 5-gallon bucket. I added one tablespoon each of fish hydrolysate, kelp and humic acid to feed the microbes. It's quite chilly in the basement so I'll keep it going for a few weeks.

My biochar get chucked in the chicken coop in their deep litter. On a very irregular basis I spread the deep litter compost on the veggie patch. By that point the chickens have thoroughly incorporated it into the woodchips, which have shredded down to fine dust as well.

When you make something like JADAM Microorganism Solution (JMS) or aerated compost tea, you can see clearly that biology peaks in just 24 - 72 hours depending on ambient temps. This says to me that the life expectancy of soil biology is brief without adequate food sources (sugars) to replicate. This is why we apply these teas to the soil at peak vitality. Therefore, my reasoning is that inoculating biochar for any longer than 24 hours isn't ideal. You'll still get the benefits of nutrient absorption and some benefits of necromass (dead microorganisms still have value in carbon), but the biology need be applied to the soil quickly so that sugars in the rhizosphere have a chance to feed replication.

In our own experiments, we found this to be true. The best results were shown at 24 hours of soaking. But we're also not stickler striving for ideal application ratios. We use vermicast tea to inoculate our biochar overnight and that's been plenty good enough. One thing you can do to see a real difference is to soil drench with JMS or aerated compost tea weekly. There's no reason you can't add biology to biochar enriched soils after applying it to the soil with adequate drenching with microbial rich liquid. We apply both vermicast tea and JMS soil drench in our market garden's weekly fertigation schedule with excellent results and all our beds are 'loaded' with biochar.

I appreciate your experiments, and your experience, E Sager.     I think the time of inoculation depends a lot on the type of inoculation. One of the most common types is to put it with your chickens or other animals, or to mix it with the compost.   I have never heard of anyone leaving it like that for only 24 hours.  

Also, I drench mine briefly once per day for a week.  The biochar is under the nutritious liquid mix for about 2 minutes, but it gets it started with the nutrition moving into the crevices of the biochar.  That is very different than soaking it for 24 hours.

I don't want to just continually soak it because my experience tells me that things become anaerobic underwater. That's how people ferment sauerkraut, kim chi and other vegetables.  I don't want to create an anaerobic situation, because it creates a condition of microbes that are unfavorable to growing my plants.  

John S
PDX OR

I have adopted what I have found another youtuber has shown for charging the biochar.      They put the biochar into their worm bin and give it months of time so that it can absorb the good stuff from the worm bin which is full of life.

Others bury the charcoal in their garden and just allow time for the char to charge.

Mart Hale wrote:

Others bury the charcoal in their garden and just allow time for the char to charge.

I think that this method works, and is probably what the original Terra Preta people did.  It's fine if, like them, you've got a lot of acreage and don't need to use that land for a few years.  

However, if like me, you are already old, and you only have a small amount of land that you can use, you might not want to give up each area that you biochar for a couple of years.   If you have a small amount of yard and a short timeline, IMO this method is limiting. Inoculation is really not as hard as giving up productivity of that land for that time, IMHO.

John S
PDX OR

John Suavecito wrote:

Mart Hale wrote:

Others bury the charcoal in their garden and just allow time for the char to charge.

I think that this method works, and is probably what the original Terra Preta people did.  It's fine if, like them, you've got a lot of acreage and don't need to use that land for a few years.  

However, if like me, you are already old, and you only have a small amount of land that you can use, you might not want to give up each area that you biochar for a couple of years.   If you have a small amount of yard and a short timeline, IMO this method is limiting. Inoculation is really not as hard as giving up productivity of that land for that time, IMHO.

John S
PDX OR

Yeah,  

All depends on your needs.      I ran into a guy who steams his to clean out the pores of the biochar....        

I considered soaking the biochar in different fertilizers like epson salt etc  to have a slow release fertilizer....    lots of options out there....  do what is best for you...     I love hearing what others do.

I tend to just go the slow route and add my biochar to my compost pile as I add organic matter to it and consider it inoculated when the compost is finished.  I also add it to the base of sheet mulches or even just throw it under my trees in the fall to drop down into the leaf litter and inoculate as the leaf litter breaks down.  Pretty much anywhere there's organic matter breaking down feels like a fair target to me!

Greg Martin wrote:I tend to just go the slow route and add my biochar to my compost pile as I add organic matter to it and consider it inoculated when the compost is finished.  I also add it to the base of sheet mulches or even just throw it under my trees in the fall to drop down into the leaf litter and inoculate as the leaf litter breaks down.  Pretty much anywhere there's organic matter breaking down feels like a fair target to me!

I take the same slow-motion approach. Biochar goes into the chicken coop. Chicken coop cleanout goes into the run to slow compost. Slow compost gets harvested as needed and used on the property.

I just tried my dirty fish tank water, horse Manure ,urine and a bit of Molasses

Sounds like a good mix, Charles. Like others have mentioned, your situation is the determinant. My assumption is that people who put it in compost don't need it right away.   I have a small gardening area, and I want to get all of it biocharred soon.  I don't make enormous quantities each time, so I use the liquid method, with convenient materials because it's faster.  

John S
PDX OR

I'm in the 'throw it on the garden and let time take its course' camp. A lot of it gets buried a couple feet down in the leaf and garbage pits. A year or two later it gets dug up and spread around when I dig a new garbage pit that fall. I plant right on top.

Have not noticed any fertilization problems.

I'm currently burning wheelbarrow loads of char (fire safety) but everything else is frozen solid. So I'm inoculating by bringing a 5 gallon pail of dry char into the basement shower and peeing on it until it floats. This is good for reducing the load on our creaky septic system, and frankly I didn't realize that I apparently pee like a racehorse. I've already "floated" three pails.

You don't need to brag!

I work hard to stay hydrated sir. A few beers also help with production.

I don't think I would have that statement emblazoned on a T-shirt though.

It's curious how the "barely floating raft" suddenly drops after a few days. I'm dealing with coarse, raw char straight from the kiln so I guess it takes a little time.

John Suavecito wrote:You don't need to brag!

He wasn't implying he could reach the bottom of the bucket while standing.
That would be bragging.