I have been dabbling with a variety of composting methods lately. I made some giant, woodchip heavy, static piles two years ago. Last year I played around with a couple different forms of anaerobic composting followed by heavy aeration, as well as some vermicomposting. All of those produced mixed results and (although if I owned my own land and could dedicate a goodly sized plot to compost I would definitely make use of large static wood heavy piles) none of them gave me the benefits of using up my kitchen/garden scraps in a timely manner while producing good quality compost. This year, the technique I am pursuing is the more traditional aerobic compost piles with turning every 10-20 days using bokashi fermented kitchen scraps, mostly sun dried (we live in the fog so 'sun' and 'dry' are relative terms) yard waste, potting soil full of rootballs, saw dust, and any other things I can get my hands on. I have just turned my current pile for the 4th time and while I am starting to see some good results there is still a fair bit of uncomposted material and there are pockets that smell like they have managed to remain anaerobic. I always break up any clumps like this that I find and also try to break up and scatter any heavily innoculated clumps.
Now my question is, those of you who make these aerobic piles, how many times do you turn them before you find they are done? Does there come a time when you turn it a final time and just leave it for however long until you need it?
Since I use a lot of manures in my compost heaps it takes one about 3 months to finish.
I turn a heap when it shows me by compression that the air spaces are collapsing, this happens the first time after about 3 weeks, from that point on it is a matter of watching for the collapse which is the signal to turn that heap.
Usually I turn a heap around three times before it is read for use, keep in mind that I do make additions of fungi and microorganisms via compost teas during the start up and about half way through (1.5 months or second turn).
If I am using wood chips in a heap those chips get sprayed down with a mushroom slurry prior to and during the building of the heap, this allows for faster decomposition of the wood chips and gives the heap a huge amount of fungi, which makes the whole breakdown faster at the end.
Any time you can smell a non sweet odor from a heap it is time to add air (oxygen) to the heap, there are three easy methods: lifting the layers, turning the heap, air injection with a pipe and air compressor.
I turn once or twice a year, but have big piles of it to. I use a tractor or bulldozer making the job easy, I just do not get there soon enough with a machine, or hate the cleaning of the machine afterwards, and put it off. It makes no difference on the compost; it is still good stuff.
I have good intentions of turning my piles but I don't. My compost gets churned a bit when I add kitchen scraps but it's more of a top dressing. Most of my compost is wood chips with the addition of kitchen scraps and cuttings. I don't spray anything on my piles and I still get mushrooms with a lot of fungal activity.
The more I plant the more I become a fan of mulching in place. I'm also moving toward the creation of beds vs pots for propagation. Things take longer to get going this way but it leaves you with strong plants/trees.
I know this isn't always an option, especially, if you are propagating in pots or trying to improve a bed that you need to use. Lately, I have been leaving bigs piles all over the place. I'm not sure how that's going to work but I figure it creates microclimates. I'm trying to let nature do the heavy lifting.
Thank you all for your replies. I think I am going to let this one sit for a while and see if I can't end up with some wonderful finished compost in another month or two. My continuing issue is dealing with our kitchen scraps. I feel like it builds up and the best plan I have is to keep turning it into my compost, but then it seems like the compost never finishes. Might just have to store it up and build another big pile in a few months when I have a whole bunch stored.
I started a compost over my head. Then found out what I had in the pile was not sumac branches/leaves, but black walnut! So removed pile to back of property. And started sort of ... Got a pile of wood chips dumped on my lawn. So now dumping my compost on this pile as a reduce the wood mulch pile. The more compost is turned in warm weather, the faster you can make compost.
I compost several ways. Mostly more or less like Scott mentioned. Those big piles I usually only turn twice a year. Once this time of year before adding more leaves & used chickenstraw to the giant piles. Once in the spring after removing the finished product from the bottom layer. In the fall (like today) I mulch my gardens with several inches of raked leaves. This year I started spreading mushroom slurries & adding old cow pies almost daily. Small amounts in the garden, large amounts in a new hugelhole I'm developing. I'm starting to raise worms again so they get most of the food scraps. Some of the worms get tossed into gardens & every compost pile.
Argue for your limitations and they are yours forever.
I compost in "dalek" bins. Weeds, kitchen scraps, lawn cuttings go in the top until the bin is full, or this summer when there was harldy any grass to cut it never filled up. Then I take off the unrotted top layer to start a new batch, haul the half-done stuff up the allotment in bags and layer it in another dalek with chicken or horse manure. Then it sits until spring and goes on or in the soil. Otherwise I don't bother intentionally turning.