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Yeast fermentation for composting solution? Answered

I threw some hay off my lawn and some green weecds into a garbage can, some sugar and yeast and formented it to slug beer but the slugs did not like it. It then fermented further to vinegar, and a crust of green "Mold?" covered it. seems to have protected the vinegar from further fermentation. I tried a second bigger batch ( morning glory weeds) with less sugar but after a few days of good fermenting it went rotten and stinky. So there are probably thresholds for sugar content. Would the yeast be a way of adding fertilizer to organic gardens? Yeast can (I think) convert urea and nitrate to protein. Perhaps some green stuff has enough sugar to work without sugar addition. vine prunings? maybe. The first batch, i put bleach in to kill off microbes before I added water and yeast. Perhaps hydrated lime would work instead of bleach and also get the ph good for yeast fermentation. This might be a cheap way of liming your garden. (Here in victoria, hydrated type s lime is cheaper than limestone for garden addition. (But it contains more calcium!) The "yeast tea" or vinegar tea could be used on the garden and the weeds could then be transfered to normal compost or used as mulch. It might be an alternative way of using diseased materials of composting seedy weeds to kill the seeds. Brian



6 years ago

Soo... The quick answer here is both ways of fermenting that hay resulted in a fermentation product.
The trickier thing is what was that product.
You mention the first batch as having ethanol and turning to vinegar... that's actually a two step fermentation carried out by two seperate biological entities (yeast and bacteria respectively).
If you didn't clean out the barrel sufficiently, contamination can alter your results, but, assuming contamination wasn't a factor, bear in mind that different types of fermenters, even ones that aare closely related, will differ in their products greatly.
Natural yeast is much different then domesticated yeast, as anyone who makes sour dough can attest.
As for what conditions to maintain during fermentation... that's dependent on the organism(s) your focusing on. Some actually prefer an acidic environment, others a basic one. so... research the beast you're trying to employ.
I'd say the second fermentation, you were trying to rely more on native yeasts.... if this was the case, i would not add sugar. They're slower growing then domesticated yeast and do not require as much sugar to do an equal job. They do require more time to do that job though.


10 years ago

This method of composting might be useful: Bokashi composting using EM or effective microorganisms- http://en.wikipedia.org/wiki/Bokashi_composting

Most likely ( Im not a field technologist) you could optimize growth by creating your own "Indigenous Microorganisms" - check out this Instruction guide on how to cultivate using white rice: http://www.ctahr.hawaii.edu/oc/freepubs/pdf/BIO-9.pdf

Indigenous Microorganisms came from Korea -- Search for Cho Han Kyu's manual called "Natural Farming" which is a recipe handbook for creating these IMs -- maybe available in the Janong Institute.


Reply 10 years ago

Thank you very much. You see! I am not mad! And my suggestion of adding calcium hydroxide probably also has merit to reduce the acidity and get the compost tea into use right away. Maybe the bokashi people thought of this too? Brian


Reply 10 years ago

Yes. These are traditional concoctions, we have gathered thru the years from our agricultural concern in the Philippines. The Indigenous Microbe Recipe Handbook ( The Natural Farming manual) with me has around 5 IM recipes mostly on a. decomposing the plant waste and b. creating enzymes and lactic acids that suppress diseases in the soil. Unfortunately, I cant scan it to the computer (its basically a thick manual I got it from one of the Universities here in Cagayan de Oro. ). However, the web is full of similar manuals, and you can get the recipes here:

(Philippine ingredients)
and here

(Korean recipes)


10 years ago

I'm not too sure why you want to do this, but Yeast doesn't like basic conditions so I'd advise that you add lime directly to the soil.
Fermented grass (done right) becomes animal feed.



Reply 10 years ago

I live in a city and I have no cows. We compost instead. But compost does not always kill weed and grass seeds. (It has to get very hot) It also does not kill mold and mildew so you cannot compost diseased plants. One of my batches was morning glory which is not acceptable animal feed, composted or fresh. And morning glory strands survive composting sometimes too. Beer and alcohol is toxic to many molds and a week soaking in 6 or 8% alcohol might kill weeds too. The hydrated lime is an option to kill off bacteria before you introduce the yeast. You do not need much if you spray it in first. and it can scrub the co2 that the yeast produces. It may be useful to break down cell walls for a day before adding the yeast. Adding urea or nitrate to the mix gets the yeast to convert it into yeast protein. This should please people who want to go organic but still want to sneak in nitrates into their system. Compost tea comes from compost. Yeast compost tea may be as good or better. After the yeast fermentation, an acid fermentation takes over. It smells quite vinegary now. I think it is also quite a lot quicker than the dry compost option.