Ratio of what to put in compost bins/piles

Liberty7

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I got this from the book 'Great Garden Fix-Its.'

It says you should have a CARBON-to-NITROGEN radio of 30-1.

CARBON NITROGEN

Cardboard bits Alfalfa
Cornstalks Bloodmeal
Dry leaves Coffee grounds
Sawdust Fresh weeds
Shredded paper Grass clippings
Straw Human hair
Wood chips Kelp meal
Kitchen scraps
Manure

P.S. In the plastic coffee can that I keep in the kitchen for putting kitchen scraps, I tear off my name with address from ALL mail and magazines and tear it into little bits and put in this kitchen scraps can which ends up in the compost.
 

Texan

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Liberty7 said:
I got this from the book 'Great Garden Fix-Its.'

It says you should have a CARBON-to-NITROGEN radio of 30-1.

CARBON NITROGEN

Cardboard bits Alfalfa
Cornstalks Bloodmeal
Dry leaves Coffee grounds
Sawdust Fresh weeds
Shredded paper Grass clippings
Straw Human hair
Wood chips Kelp meal
Kitchen scraps
Manure

P.S. In the plastic coffee can that I keep in the kitchen for putting kitchen scraps, I tear off my name with address from ALL mail and magazines and tear it into little bits and put in this kitchen scraps can which ends up in the compost.
Really, 30 to 1? Wow, I am way off base. I have two piles of horse manure that I am keeping a little moist so that it will heat up. I may be doing this wrong. Dang it. Now I am more confused that when I started.
 

patandchickens

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Sorry, but NO NO NO NO NO. (I have also posted this on the other thread where this info came up, b/c it's important...)

That's the *atomic* ratio you want, but it has nothing to do with the ratio OF MATERIALS. If you make a pile with 30 parts sawdust to 1 part manure, it will take approximately forever to break down :p

This 30:1 business is a useless concept unless a person is inclined to look up book values for the C:N ratios of their materials (which still may not be quite accurate for the particular stuff you've got) and then do some calculator work to figure out how much of each will give you that ratio.

A more USEFUL guideline, for those disinclined to doing math (tho it's really pretty easy), is to aim for somewhat more brown stuff than green stuff in your pile, but not *vastly* more brown than green.

(You will see different brown:green ratio numbers quoted in various places. IMO in large part that is because they're making different assumptions about what your likeliest brown and green materials are. But you know what, unless you are in a giant hurry [in which case, get out your calculator and also just learn to know how your materials behave], it just doesn't matter all THAT much, you only need to be in the general ballpark to get pretty decent composting rates)

(So, a big pile of horse manure with just a modest amount of bedding mixed in, actually ends up being just about perfect for composting)

Pat
 

muddler6

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WHat I do, and most people I know, is mix what you have when you have it. I have taken to mixing my grass clippings in with the compost that is started, and if I need some more browns I run the mower over the leaves at the edge of the yard or I go to the manure pile with all the wood shavings and straw mixed in it. I had some great stuff to add t the garden this spring. I have sectioned the compost bin off and leave a little at the bottom,add grass, then a little composting "Stuff" and any fresh kitchen scraps, then come back around with the bagger or grass and repeat. We have had enough rain so I don't have to add any extra water right now, and it is heating up and breaking down great! My advice, don't get too scientific, it takes the fun right out of composting (don't tell my cooperative extension office that I said that ;) )
 
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