The Immutable LawsCarbon/Nitrogen Ratio: = 30:1This is the first law one has to adhere to in order to ensure
rapid composting. Every ingredient you add into your
composter has it's own inherent C/N ratio, like
- Grass clipping = 15:1
- Soft wood chips = 226:1
- Vegetable Waste = 11:1
- Poultry Manure = 10:1
What you decide put into your composter the first day is the
weighted average of each of the individual items' C/N Ratio.
My ingredients, for example, are predominantly Grass Clippings
and Soft wood chips and I have computed my ratio to be 3 parts
grass clippings and 2 parts soft wood chips. You have to
perform the same calculation as I have, in order to arrive at
your final predominant ingredient ratio. Luckily there is an
online Free Java enabled C/N Ratio Calculator that helps you
perform this calculation. I also add a minuscule (compared to
the above ingredients) amount of kitchen waste.
Note: Remember to cut everything down to 1.5" size.
WaterA 50% water content is necessary. This means the composter
may have to be watered from time to time if it appears dry and
the side vents will have to be left open if it appears wet. 50%
water content is as wet as a wrung out sponge. If you see
water settling on the bottom, it is too wet.
TemperatureIf the composting conditions are correct, it (the waste) will feel
hotter than ambient, surprisingly quite hot. It will continue to
feel hot until the entire process is done unless there is
something seriously wrong.
After the 3rd day of composting, when the waste (future
compost) has gone down to half it's original volume, the 55
Gallon drum is now only 1/2 full. This amount is below it's
critical mass and will loose heat at night when it the ambient is
cooler. This way you will loose 8 hours of valuable composting
time cutting into your 17 day harvest cycle. What I do is place a
20mil plastic sheet over the waste in order to insulate the
material and speed up the process.
AerationTurn the barrel at least once every day. If you do that, the
entire process will take 2.5 weeks, or 17 days. If you turn every
other day and all other conditions are correct, the process will
take 25 days. Quite an amazing feat, considering a left alone
compost pile will take a whole year to mature.
Fine TuningIf you keep to the turning/tumbling schedule, one of 3 things
can go wrong and needs to be rectified mid-course.
- Add/subtract Water.
- Add Carbon rich ingredient (High C/N Ratio).
- Add Nitrogen Rich ingredient (Low C/N Ratio).
As long as the ingredients are moist, a pile not heating up over
120˚F indicates not enough nitrogen, while one that smells bad
indicates not enough carbon. Either condition can be
corrected by adding the required ingredient.
Note: Never add anything else, mid course, or your 17 day
timetable will be altered.
SummaryThis magical transformation within such a short time in a
tumbling composter is almost a miracle of nature. The end
product is this sweet smelling black gold that has to be sun
dried for a day or two (10% moisture content) and stored or
used immediately in your garden. The original paper, "The Rapid Composting Method" from UC Berkeley pioneered a lot of this
study and provided empirical recomendations