Compost Pile
The first is that the minimum size for effective “hot” composting is 4 feet by 4 feet by 4 feet tall. Anything smaller than this will not heat up enough to kill off bacteria or weed seeds. Smaller piles will “rot” down or produce what is sometimes called “cold” compost.
This obviously creates a bit of a problem in that few of us have enough organic material to create this large a pile with our day to day refuse. I note the exception to this is our leaf collections in the spring will often fill this size of container quite nicely.
Step One
A compost pile then is built up of carbon and nitrogen sources in the ratio of 30 percent nitrogen to 70 percent carbon. Some resources tell you that “green” organic sources such as grass clippings or lettuce leaves are “green” while other material such as leaves are “brown”.
Bacteria & Fungi in Your Compost Pile
This usually works this way because bacteria break down the nitrogen or “green” sources while fungi break down the cellulose or “brown” organic matter. And we need both to create good compost as they work in tandem in breaking down organic matter.
When I was building large bins at the farm, I would usually start with something quite coarse and fibrous at the bottom of the pile. I usually used straw and leaves down there if possible. I'd build a foot thick layer.
Then I'd add a 6-inch to foot thick layer of green material whether it was household waste or barn manure.
Then a few inches of garden soil would be spread equally over this mix. The garden soil provided the necessary starter bacteria and fungi to get the pile composting.
This would be repeated until the 4x4 bin was full.
I'd water it and then walk away. The bin would start to heat up and I'd simply let it do its thing.
Step Two
The compost pile would invariably heat up and if I waited a month or so, it would start to cool down again.
As soon as it started cooling down (use your hand as a guide – when the internal temperature lowers down to where you can put your hand in there comfortably) you can turn over your compost, mixing it up and getting it ready for a second heat cycle.
It will heat up again.
At this point, you're going to notice your compost pile has shrunk considerably. This is fine and expected.
Step Three
Some gardeners repeat step two again. I never did because I was too lazy and was happy to let the compost work itself. I was happy with the product I produced and the plants never seemed to complain.
A Confession
Having said all that, I have a confession to make. While I would occasionally produce compost in this work-intensive manner, the bulk of the house produce was simply tossed onto the top of a compost bin of the correct size and allowed to sit and freeze over the winter.
The spring and fall cleanup debris was used to top up the bin and get it to the right amount of material for composting but I seldom spent the time or energy to turn it.
The compost produced was fine without the turning although it took a little longer to make (I merely had two bins to handle the extra material)
So while you will read the recommendations to do all this turning work, it really isn't necessary on the home scale unless you really need the heat to kill off weed seed.
Do you have a question about a compost pile?