What's Going On
Composting is the process of turning rottable waste into soil. Through erosion of inorganics, and the feeding of life on organics, EVERYTHING becomes soil...eventually. Your job as the gardener or farmer, is to accelerate this process as much as possible. The three constraints (other than time) are: money, work and space.
This model for farms minimizes time, and effort, but costs a bundle, and takes up a lot of space.
I choose a tumbler for composting because it decreases time, is affordable (for me) and eliminates the problems of pests.
Composting is Easy
Anything that rots can go into the composter. If it is possible for it to get moldy or smelly, it will rot and can eventually become soil. I err on the side of "Whatever, just throw it in." If it was a bad idea, I won't use it again.
Composting is Hard
Again, we come to constraints. Everything will become soil eventually, but we want to maximize the speed with which this happens. There are some basic rules for this.
- The right ratio of carbon to nitrogen is about 30:1. In practice this is about equal parts brown matter and green matter by volume.
- The right amount of water. People say "like a damp sponge", which is a bunch of crap for two reasons.
- The stuff at the top of the pile, where you are checking, is dryer than the stuff at the bottom.
- A pile can get wetter or dryer within hours, so you sort of have to guess what it is going to do in 3 days.
- There is never an occasion where rotating the pile is bad.
- A compost pile is a living ecosystem, it's alive and needs to be treated like a plant. There are various levels to which you can care, and it is possible to kill it, in which case you have to (mostly) start over. It requires:
- A seed (all plants have the microbes needed to start a compost pile, although those that have never been in a refrigerator or subject to chemicals are best)
- Food - brown matter and green matter
- Water - but not too much
- Air - never seal a compost pile, it works faster and stinks less with air
- Heat - fortunately a compost pile can create its own, and cannot die of chill
- A lack of poisons - anything that kills bacteria or fungus: bleach, oil, preservatives, vinegar, alcohol etc.
- A lack of "weeds" (other organisms that aren't the ones you want), which is why you dont put things like dead animals and dog crap in it.
How to start
- Get some green plants (kitchen scraps, grass clippings), get some brown matter (dead leaves, straw, shredded paper).
- Put them in the composter until it is at least half full, the fuller it is, the more heat is will be able to retain which will make everything go more quickly.
- Water it till it's sopping. Most composters can leak out the bottom, so just go to town, the rest of the water will evaporate out the top, or leak out the bottom.
- Rotate the pile, the idea is to not miss anything, make sure all your brown matter is wet.
- You have now started the pile - that is it.
How to maintain
- I check on my tumblers whenever I'm bored, which is every 1-3 days. Check at least once per week, give it a spin, and open it up to check its smell and temperature.
- If it is hotter than ambient temperature, you are doing well, nothing to be done. The hotter the better - municipal compost piles can get to 160-180 deg F, but you have a rinky dink little pile, and can't hope to get that so don't worry.
- As long as the pile is above ambient temperature, you can add stuff to it.
- If it smells like piss or ammonia, there is nitrogen that is not being used, add brown matter and top off with some water.
- If it smells like muck, low tide, or a bog - it needs more air and less water. Rotate the pile, if it's early in the process, add brown matter to keep the pile from collapsing (thus allowing more air in the pile), and to absorb water. If it's hot out (>80 deg F), rotate the pile and leave the lid open for the rest of the day.
- If there is brown matter that has not broken down - add more green matter, or pee on it (for guys), girls can use a measuring cup on the toilet.
- If it smells like rotting flesh - Never add that much meat to a pile ever again. Add more green/brown mix. Nothing really to do except wait the 2-3 weeks for it to go away. Lie, and tell the neighbors it was not your fault.
- If it's winter - make the pile bigger, do not add water. Any freezes will break the cell walls of the green matter and release water into the pile. Always keep the pile full and big.
- If there are these round turd-looking clumps in the compost, that when broken apart have a strong smell, undigested green matter or are warm - Add a lot bunch of brown matter, and a lot of water. The clumps need to be broken up so that they can be exposed to air and break down.
- If there are these round turd-looking clumps in the compost, that when broken apart look like brown mush that doesn't smell, or feel warm. You are done with the primary composting. Time to let it age.
How to age
This is the part of the process where you can get the compost to get hot, but it still looks more like garbage than soil. This part takes 1-3 months, instead of the primary processing which takes 1-5 weeks.
When I start this stage, I have a bunch of impenetrable brown/grey turds of grass and cardboard fibers. They need to get broken up.
What I used to do was let them dry out in a garbage can, and then when they had the moisture of modelling clay, I would shred them on chicken wire sieves. That was a big waste of time.
The better way I found was to add a whole bunch of coarse sand (the stuff they use to make concrete), and add water and toss it in a tumbler. The sand coats the outside, but when a turd breaks up, the sand coats the new smaller turd, and they can't re-form.
- Add sand and turds to the tumbler.
- If there are uncoated turds, add more sand.
- Spray with water.
- If there is dry sand, add more water.
- Using a 3-tine hand rake, stab into the largest turds at the top of the pile and fling them apart.
- Rotate and repeat step 9 at least once per week.
- If you see mold, or smell anything, or have turd's over 1" in diameter, the pile is not done. Rotate it, break up some turds and wait another week.
I've never actively tried vermiculture, but aging compost is what you would probably put in a worm pile/bin, since the pile cant produce neoughheat to harm the worms.
This aging step is mostly to make the compost more manageable and finer. It also gives a chance for any pathogens introduced via dog crap or meat to die off. If you are fertilizing inedibles, this step can be skipped entirely. Any aging that needs to be done can be accomplished by worms and pill bugs.