Composting 101, for the beginner

[Alfred]

My experience with composting is it needs plenty of air,it should be kept moist but not wet and also i give it some lime which contains calcium that is an essential plant nutrient.

[dave.c]

I used to live in Portland, OR. That's the first time I saw a compost bin. They had all the warms and everything, it was great. I had a window bin till now, cause we lived in an apartment but now that we FINALLY have a yard composting will be number one on my list. Thank you for all the info!

[pickupguy07]

How does a person achieve this combination?
Everything has a C:N value, and here are some values of ingredients....

Leaves (fallen, brown in color) - 50:1
Paper - 400:1
Grass clippings - 15:1
Fruit scraps - 35:1
Vegetable scraps - 20:1
UCG's - 20:1

*Mix ingredients by volume, not weight.....

If you combine equal parts of leaves and grass clippings, the overall C:N ratio would be 32:1

- leaves and UCG's, the overall C:N ratio would be 35:1

- paper and grass clippings, the overall C:N ratio would be 207:1

If paper is your only resource of browns, you will need to add TONS of greens to achieve an overall mixture of 30:1. It would be something like -

1 part paper, 20 parts grass clippings - for an overall combined C:N ratio of 33:1
*Needless to say, paper is not a good choice of browns......

Nice info.. Needless to say that we all have different sources for our compost at different times of the year.
One thing I wanted to ak is about "how" you figure the C:N ratio. I tried several different ways based on your examples.
Could you pass along how I can figure the ratio depending what I have on hand. For example I can get 100 lb of used coffee ground per DAY... but at this time of year very few browns.. only newspapers mostly.

Needless to say I'll have to look over the greens/browns list and see what else I can come up with for browns.

Couple other things.. I see paper is listed at 400:1. Is regular 'paper' and newpaper figured the same. I know that regular 'copy paper' is a lot thicker than newspaper.?? Curious if the ratio was different.

Finally. I know sometimes people get referred to this link..
http://compost.css.cornell.edu/OnFarmHa ... taba1.html
I have no idea how to figure out what I am seeing... anyone know where I might find a list like you posted above. If someone tells me how to figure out the C:N ratio and the list of items I could probably figure out a decent mixture to keep the pile going with what I have available.

[cynthia_h]

First of all, let me apologize. Such a long passage (the ratios) from an unattributed source should have raised a moderator's antennae when it was posted, and it did not.

I have just performed a limited Internet search on the ratios. You really do NOT want to calculate these yourself. One source is this one, from the University of Idaho extension service; other detailed C:N lists can be found in the lists and links referred to in the extended threads you've been to and through already, as well as others in the Composting Forum. I believe that, elsewhere, a "rough and ready" guideline of 2:1 is provided, and that is volume of Cs to volume of Ns, not ratios or anything else.

I haven't seen any postings from the OP of this thread since last fall. I understand when people in cold-winter zones take up other activities in the winter, but I'm a little concerned about this OP in particular. His home is (was?) in one of the areas of our country hard hit by the tornadoes a few weeks ago.

Cynthia H.
Sunset Zone 17, USDA Zone 9

[rainbowgardener]

Personally, I have never calculated a C:N ratio and I have good compost every year. It isn't rocket science. You want basically some balance of wet/ dry, greens/ browns, but if it is off a little bit one way or the other, it will still compost. I use a little more brown than green by volume, by eye ball. But as noted sometimes of the year that is easier than others, so the C:N ratio of what I add does change a bit through the seasons. As long as the fall leaves I collect last, it's not hard to keep plenty of browns. Last year after the fall leaves were gone (the next summer!), I bought a bale of straw, but I wasn't real pleased with how well it broke down (or didn't) so I may try something different this summer.

But just eyeball it. If the browns aren't breaking down, add more greens/ air/ moisture. If it is wet and slimy or doesn't smell good, add more browns and mix. Nature will take care of it!!

[pickupguy07]

HI Cynthia
Thanks so much for the reply..
All the folks here are so kind and helpful...
The link you provided is a wealth of information. All very interesting stuff.

In doing other research I did find a few tidbiots about figuring the C:N ratios. Of course finding out what the amounts to figure can be difficult.
I'll post what I found and someone can correct me if I am wrong.
Basically I read that you take the ratios... add them together, and devide by thye number of items.
For example lets say you have 1 part leaves (50:1) and two parts UCG (20:1) SO you take 50+20+20 = 90 devide by three items 90/3 = 30

Obviously I assume the more varity the better - I am guessing you wouldn't want to make compost out of just weeds and wood ashes... even though the ratio comes up to about 28.

I have access to 400 - 500 lb coffee grounds per week (maybe more)... mostly available rigt now is newspaper. Paper had about 175, and UCG about 20. so to use these tow items I'd have to use 9 parts UCG to one part paper -- and I have no clue how long it would take to break down (heard paper breaks down slow)..
So you can see why I have questions. I have some items in great supply, but few of many items util fall comes when I can collect leaves.
THANKS

[rainbowgardener]

Agree that the more variety the better. We generally say no more than 10% of your pile one ingredient. Part of what makes compost such good stuff is that by the time you have a big variety of ingredients contributing to it, your finished compost will contain all the nutrients, micronutrients, trace minerals and whatever that your plants could need, plus the appropriate micro-organisms to help process the nutrients into forms the plants can use.

[rot]

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Isn't newspaper & coffee grounds about ideal for raising worms?

Yes newspaper is slow to breakdown. Run it through a chipper with some other stuff so it gets shredded well and then mixed well with some other stuff or you'll get clumping.

I once made a bin of 50 percent coffee grounds. It was a dark gooey mess and I worked it for months to turn into something somewhat workable. Coffee grounds if not mixed and spread well through out the pile will smoother a lot of the air.

to sense
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[pickupguy07]

yeah. Iam figuring I am able to get too much of one thing, and not enough of another..
Even if I did know all of the C:N rations of what I put in the bin,.. you know you always add 'other' stuff... old garden veggies, table scraps,.. so that can skew the numbers

also I was curious.. I know it shows paper at a certin C:N ratio.. I assume that is 'whole'. I am guessing if it is schredded that number goes down some... I am hoping (would anyone know what that number may be.??)

My pile is just a newbie.. lol. My first bin ever and maybe a foot tall.

[rot]

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If you shred the paper it won't change the C:N ratio any but it will increase the surface area exposed to air and bacteria. Like a fire, the greater the exposed surface area, the faster the process.

You want to mix the nitrogen materials into the vicinity of the carbon materials because the bacteria draws on the nitrogen to digest the carbons.

I use what I have on hand and if I can, I adjust things as I go along. Mine is more of a digesting process than a compost producing operation. I will build my bins most of the time slowly and just keep adding things until the bin gets full and I start another while the previous bin finishes digesting and reduces. I have some I turn infrequently and a couple I don't turn at all.

The hot process gets you compost faster and kills off seeds and pathogens. It takes more work because you are turning it frequently.

Ideally in the hot process you monitor the temperature and just after the peak temperature starts to decline you turn the pile and monitor the temperature for the next peak. The temperatures decline of course but the turning still gets oxygen into process keeps things moving at lower temperatures because different bacteria are in action then. Without monitoring the temperatures, if you turn once a week, I think you'll find that plenty. Turning also gives you a look-see so you can tell if it's working or not or maybe if it needs water.

In the hot process you want to build the pile up all at once. I can get 17 cu ft going up to 150 F. Once got 160 F. Often it's at 140 F when I bother. It's a little easier to get the higher temperatures when you make the bin a little larger approximating a cu yd or 27 cu ft.

Mix some of this and some of that and see what happens. Adjust things as you go along. If it's done in two months time, you got a good mix and you've been turning regularly and adding just the right amount of moisture. If it takes a long time maybe you've got some stuff that doesn't break down that quickly or too much water or not enough water or not enough air. You're looking at a lot of variables from climate to materials to energy put into it. Slow and dry means to many carbons, smelly and wet means too many nitrogens typically.

Observe and adjust. Don't stress over it.
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[rainbowgardener]

Definitely agree with rot "don't stress over it"

but re 'My pile is just a newbie.. lol. My first bin ever and maybe a foot tall."

Look around for more compostables... they are everywhere! Your compost pile will work a lot better when it is deeper.

[Ole Dummy]

Started my compost pile yesterday. I tried this a couple years ago and got so much bermuda grass growing in it I couldn't do much with it. Moved to a different location but there is still some bemuda there. What do I need to do about keeping the grass from coming up in it?

[rainbowgardener]

Before you start your pile, cover the whole area with cardboard, which will smother the grass. Put your pile down on top of the cardboard and the cardboard will eventually compost away. But I think you would need to make the cardboard area wider than the compost pile to make it a little harder for the grass to grow back in from the outside.

[Ole Dummy]

Thanks, I hadn't thought of that.

[rot]

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WRT the list of materials link:
http://compost.css.cornell.edu/OnFarmHa ... taba1.html

The way I use it is as a spectrum. There will be few regular feed stock items for my compost higher in nitrogen than grass clippings and fewer high in carbon than say sawdust. Most other things fall in between.

So if I'm wondering just how green or brown something might be and it's on the list, I can compare it to the grass clippings or the saw dust or the leaves or something I have used and know how it behaves and with that knowledge, I will anticipate how I'll need to adjust things to accommodate any particular feed stock that falls into my hands and pops up on the list.

I find do or don't lists less than helpful when I don't understand the why. Most of the time, stuff on the don't list works for me as don't want to for various reasons. Sometimes stuff on the do list turn out to be don't want to either.

If you want to learn while you're starting out, stick with the sure to compost stuff at the beginning and see how that goes. Once you have an understanding how it works for you, go from there. I think you'll find it's no great leap to draw your own conclusions. You'll notice things like peach pits don't break down so maybe adding a bunch of peach pits won't be a such a hot idea. After you've turned a pile or two, you might get a notion of what you don't want to uncover and that will guide you further.

Start, observe and, adjust.

to sense
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