What Goes In My Compost Bin

This is is a list of the things I put in my tumbler bin, including a bunch of things that are unorthodox. The line for me is “will it compost”, which manages to include things like chicken bones and junk mail and excludes things like bottled juice and paper towels.

• Okay

  • Tissues
  • Napkins
  • Cooked chicken bones
  • Coffee grounds and filters
  • Egg shells
  • Spent egg wash from deep-fry sessions (that is if I don’t give it to my dog first)
  • Paper – I put all my spent paper and cardboard through a cross-cut shredder. This acts as my brown matter, since I only have 1 tree on my property.
    • Printouts – I double-print from a laser printer for my job at home
    • Corrugated cardboard – I break down the boxes into sheets, then cut it into strips 2-4 inches wide and then stuff it into the 12-sheet cross-cut shredder. I did this to a $50 shredder from Costco for 2 years before dulling the blades/teeth enough that the motor couldn’t handle the torque.
    • Junk mail – little plastic windows and all
    • Newsprint – newspapers, color advertisements, etc.
    • Single sheet cardboard – from those soda boxes with the handles
  • Urine – a great way to get some extra nitrogen into the compost pile. Note: urine + paper will not yield a viable compost pile since both materials are non-living – there just aren’t enough different types of molecules to support a living ecosystem of micro-flora.
  • Ash –
    • too much will slow/cool down your batch – maybe best to mix in after your batch has done with its hot phase.
    • This isn’t so much good for the compost micro-flora, but has nutrients the plants will appreciate (phosphorous and potassium).
    • Note that ash is generally basic, so if you have basic soil (high pH / pH>7.5) this is a bad thing.
    • Coal, has heavy metals in it which get absorbed into plants in proportion to how much there is and eventually the rest of the biosphere.  (http://www.sciencemag.org/content/191/4230/966.abstract) Will be discussed in another post.

• Nokay

  • Raw bones (I give those treats to my dog, he eats them like carrot sticks)
  • Cooked other bones e.g. pork ribs (too big to compost well – maybe if I had a wood chipper)
  • Bottled juice – the preservatives in it can kill the stuff in your compost
  • Milk products – they turn to cheese and don’t really decompose.
  • Oils – it doesn’t rot in the bottle, why would it rot in a composter? Oil is a preservative since it limits access to air and prohibits the exchange of water.
  • Pickle juice/Brine – Also a preservative, too much will kill your micro-flora
  • Paper towels – they don’t break down, and at least Bounty's have a habit of getting stronger in the hot humid environment of the composter.
  • Dog crap – covered in a previous post

Edibles need compost

In Maryland we are about halfway through the growing season here ( I guess everyone in the northern hemisphere is). Anyway, I learned some things about my experiments this year. Earlier this spring I put a bunch of compost at the base of my Fig (Celeste) and Mulberry trees but not my mint patch (on the advice of some website or book that said the mint "wont miss it").

The most practical reason I have found for composting is that it makes edibles more tender. Wood is made from carbohydrates (cellulose), which requires lots of carbon to make.  When a leaf or fruit is "woody" it has too much carbon in it as a result of not having enough nitrogen available to produce leaves or fruit properly.

Last year we were really disappointed in the mulberries our tree produced they had very woody centers that had to be spit out they were so hard. This year, I poured 1-4 cubic feet of compost at the base and I noticed the difference months later when the berries came in. They were much sweeter and much softer. Even better, they didn't have those plentiful little gnat-like bugs running around in them.

My neighbor is much more of a farmer than I am, and he gave us a bunch of beets in early spring. When all the stores and farmers markets had wonderful sugary beets with soft lovely greens (which I like a lot more than the actual beets), his greens were woody and the bulbs kind of tasteless. I don't know if those had been composted, but he basically has the same soil I do, the useless kind. I saw his compost pile a few weeks before he gave me the beets. It is based off of coffee grounds and newspaper that he gets from Starbucks and newstands around the area. It had ants in it and was very dry. If that's what the beets were made of then I would say that his pile had too much carbon in it and not enough nitrogen. Regardless, the beets were woody.

Edibles need compost to be tasty.

Oh yeah, and compost makes them grow about twice as fast in my experience.