That's amazing! That's the beauty of them being so low maintenance once built - you can build many for low cost and let them do their thing. I hope you keep making soil!
Also, I need to tell you that your post reassured me that I was on the right track. My doubts were triggered by the discussion on how much N material should be included in the bioreactor. I went for mostly carbon material and very little nitrogen because I wanted really diverse grous of microorganisms. The result was that my bioreactors didn't heat up. That made me worried when I compared posts on Facebook which showed high temperatures and people were claiming that their Johnson-Su compost was the ideal one because it underwent intense thermophilic heat. But your findings that these hot bioreactors had the lowest fungal count as compared to the cooler ones cleared my doubts away.
Yeah, I’ve always been curious why people equate heat to great composting. Heat is a tool not a marker of quality, it can help kill weed seeds and pathogens, which may be necessary (and only if the feedstocks contain weeds and/or sources of pathogens like manure or putrefied food scraps).
But with the Johnson Su, those types of inputs aren’t (typically) included so it’s in our best interest to not torch the microbes! Even when some manure or food scraps are added, as long as they were mixed with majority carbon it shouldn’t be a concern after the length of aerobic composting that takes place.
Not to mention, ironically, when you add a lot of nitrogen to a composting system it can actually end up with less N in the final product because all that heat it generated is essentially blowing off nitrogen 👋 Dr David Johnson also found that there were less N-fixing bacteria in bioreactors that had too much initial nitrogen!
So yeah, heat is disruptive and like tilling it’s a tool that should be used very intentionally while understanding the risks/loss associated with it. Im glad you feel better about your lack of heat in this case 🤗 Speaking of warmth, I do expect your tropics to speed up the process - keep us posted! :)
We have a tropical climate where temperatures will never go below 22°C. So I am really curious how fast this thing gets going. I still want to follow the minimum of 9 months.
I just sent you a copy, Sharon! Thanks for making a pledge this year, it means so much 🤎let me know what you think of the guide once you have a chance to read it.
I just emailed you a copy, Noey! I hope you find it useful as you nurture your south TX soil, let me know what you think. Thank you so much for your pledge. Warmly, Andie
Andy - I'm finally getting ready to build a modified Johnson-Su and have immediately run into a stumbling black. I plan on using concrete re-inforcement wire for the outside cylinder. What I have is 5ft wide. I want to use 1/4 inch 19guage hardware cloth for the inner tube but I can't find rolls of it sold that's 5ft wide. Since you don't mention (as far as I can see) splcing two narrow pices together (3 ft wide overlapped?) I'm writing to ask if that's ok. (overlabbing the 3ft wide closth by 12inches and 'sewing' together the two pieces with wire) I don't see any harm in using heavy landscape cloth without hardware cloth on the base, what do you say? WIll appreciate your advice. Thank you!
100% a 12 inch overlap should hold up nicely for the inner cylinder, good thinking. I also tend to use a 1/4" hardware cloth on the base without the landscape cloth, seems to work fine. If you're in an arid climate I could see it drying out faster without the landscape cloth on the base, so just monitor moisture near the base (in addition to the top) to gain insight on that. I hope you have fun with your first build! Keep me posted :)
Oh, this ain't my firsst build ;-) It's my first Sexy build. I have landscape cloth already to cover the pallet but I don't have hdw cloth to do that so I was wondering if I could skate on the pallet hardware cloth However, if hardware cloth is a much better choice, I'll get more hardware cloth. Frankly, I don't see hardware cloth as 'breathable' compared to hardware cloth. Am I wrong about that? (Oh, thanks for the Sunday answer!!)
Haha, I see! Glad you're giving this version a try in that case.
Okay, so it sounds like you want to use landscaping fabric/cloth in place of hardware cloth for the base - am I understanding that correctly? My concern is that the weight of the material might make the landscaping fabric sag and it could tear and spill some contents over the course of the long duration of the composting process - Do you know what I mean? If you think it's a thick enough fabric and you can secure it tightly enough to the pallet base, then follow your instinct, but that is my only concern is that it might not hold up for the 9 - 12+ month timeline exposed to the elements and bearing the weight of watering / rain events.
(Also, I hope with the similar terms haven't made for a dizzying conversation about which cloth is being referenced... for example, I'm not sure which "cloth" you were suggesting is not as breathable in your last sentence 😅 perhaps "fabric" can be used to reference the landscaping material, and "hardware cloth" can be used to reference the metal mesh). I serendipitously was checking email when you wrote in yesterday!
Hi Cindy! I sent you a copy on the evening of December 10th after receiving your pledge. It was sent from hello@rhizos.science to your @mac.com email, subject line: Modified Johnson-Su Bioreactor Guide - if you can't find it in your inbox try messaging me at hello@rhizos.science :)
From the Philippines here. We built not one or two, but 10 bioreactors last October through December.
That's amazing! That's the beauty of them being so low maintenance once built - you can build many for low cost and let them do their thing. I hope you keep making soil!
Also, I need to tell you that your post reassured me that I was on the right track. My doubts were triggered by the discussion on how much N material should be included in the bioreactor. I went for mostly carbon material and very little nitrogen because I wanted really diverse grous of microorganisms. The result was that my bioreactors didn't heat up. That made me worried when I compared posts on Facebook which showed high temperatures and people were claiming that their Johnson-Su compost was the ideal one because it underwent intense thermophilic heat. But your findings that these hot bioreactors had the lowest fungal count as compared to the cooler ones cleared my doubts away.
Yeah, I’ve always been curious why people equate heat to great composting. Heat is a tool not a marker of quality, it can help kill weed seeds and pathogens, which may be necessary (and only if the feedstocks contain weeds and/or sources of pathogens like manure or putrefied food scraps).
But with the Johnson Su, those types of inputs aren’t (typically) included so it’s in our best interest to not torch the microbes! Even when some manure or food scraps are added, as long as they were mixed with majority carbon it shouldn’t be a concern after the length of aerobic composting that takes place.
Not to mention, ironically, when you add a lot of nitrogen to a composting system it can actually end up with less N in the final product because all that heat it generated is essentially blowing off nitrogen 👋 Dr David Johnson also found that there were less N-fixing bacteria in bioreactors that had too much initial nitrogen!
So yeah, heat is disruptive and like tilling it’s a tool that should be used very intentionally while understanding the risks/loss associated with it. Im glad you feel better about your lack of heat in this case 🤗 Speaking of warmth, I do expect your tropics to speed up the process - keep us posted! :)
We have a tropical climate where temperatures will never go below 22°C. So I am really curious how fast this thing gets going. I still want to follow the minimum of 9 months.
I would love a copy of your modified design! Sharon Crow
I just sent you a copy, Sharon! Thanks for making a pledge this year, it means so much 🤎let me know what you think of the guide once you have a chance to read it.
👍. I've had good intentions for awhile to start some bioreactors. Your post has created that final level of excitement to push me to action !
I’d love a copy of your guide. Great read! This is something we definitely need for south texas soils.
I just emailed you a copy, Noey! I hope you find it useful as you nurture your south TX soil, let me know what you think. Thank you so much for your pledge. Warmly, Andie
Andy - I'm finally getting ready to build a modified Johnson-Su and have immediately run into a stumbling black. I plan on using concrete re-inforcement wire for the outside cylinder. What I have is 5ft wide. I want to use 1/4 inch 19guage hardware cloth for the inner tube but I can't find rolls of it sold that's 5ft wide. Since you don't mention (as far as I can see) splcing two narrow pices together (3 ft wide overlapped?) I'm writing to ask if that's ok. (overlabbing the 3ft wide closth by 12inches and 'sewing' together the two pieces with wire) I don't see any harm in using heavy landscape cloth without hardware cloth on the base, what do you say? WIll appreciate your advice. Thank you!
100% a 12 inch overlap should hold up nicely for the inner cylinder, good thinking. I also tend to use a 1/4" hardware cloth on the base without the landscape cloth, seems to work fine. If you're in an arid climate I could see it drying out faster without the landscape cloth on the base, so just monitor moisture near the base (in addition to the top) to gain insight on that. I hope you have fun with your first build! Keep me posted :)
Oh, this ain't my firsst build ;-) It's my first Sexy build. I have landscape cloth already to cover the pallet but I don't have hdw cloth to do that so I was wondering if I could skate on the pallet hardware cloth However, if hardware cloth is a much better choice, I'll get more hardware cloth. Frankly, I don't see hardware cloth as 'breathable' compared to hardware cloth. Am I wrong about that? (Oh, thanks for the Sunday answer!!)
Haha, I see! Glad you're giving this version a try in that case.
Okay, so it sounds like you want to use landscaping fabric/cloth in place of hardware cloth for the base - am I understanding that correctly? My concern is that the weight of the material might make the landscaping fabric sag and it could tear and spill some contents over the course of the long duration of the composting process - Do you know what I mean? If you think it's a thick enough fabric and you can secure it tightly enough to the pallet base, then follow your instinct, but that is my only concern is that it might not hold up for the 9 - 12+ month timeline exposed to the elements and bearing the weight of watering / rain events.
(Also, I hope with the similar terms haven't made for a dizzying conversation about which cloth is being referenced... for example, I'm not sure which "cloth" you were suggesting is not as breathable in your last sentence 😅 perhaps "fabric" can be used to reference the landscaping material, and "hardware cloth" can be used to reference the metal mesh). I serendipitously was checking email when you wrote in yesterday!
Hi Andie! I’d love a copy as well. We are going to try one in the backyard. Thank you Cindy
Hi Cindy! I sent you a copy on the evening of December 10th after receiving your pledge. It was sent from hello@rhizos.science to your @mac.com email, subject line: Modified Johnson-Su Bioreactor Guide - if you can't find it in your inbox try messaging me at hello@rhizos.science :)
Awesome thanks! It was in my junk