…..Aaron's EnvironMental Corner…..

Composting Basics

Filed Under: Do It Yourself, Organic Gardening on July 12, 2009

There are three types of compost: manure, compost, and mulch.  Their value for your garden is in the order listed there.  Manure is compost made by sending plants through a biological processing unit (aka cow, horse, pig, chicken, etc.) and is the easiest compost to get ahold of and usually the best for your garden overall.

Of course, that doesn’t mean you should use it exclusively.  Traditional compost, which most gardeners and organic farmers are intimately familiar with, has definite advantages too.  Not the least of which is that it gives you somewhere to put the weeds from your garden and more control over its composition.

Mulch is basically just compost that’s waiting to happen.  When it’s used in gardening, it’s usually put down as “top cover” or as a border to provide a buffer to keep weeds at bay.  As top cover, mulch can be spread over a garden or shallowly tilled in and allowed to compost on its own over time.  This is a good way to provide both protective cover and a nutritional source for your garden during the bare, winter months.

Of the three, traditional compost requires the most work on the gardener’s part.  That work is greatly reduced, though, once you understand what’s needed to make good compost and how to utilize a little knowledge to make the job easier.

How Composting Works
The basic idea behind composting is that all things rot, break down, spoil, etc. Every organic thing will eventually become the soil from which it came. Plants, animals, fish, etc. all eventually die, return to the soil, and then become more plants, animals, or fish. It’s the cycle of life.

When you compost things in a controlled manner, you’re utilizing this natural process and speeding up the breaking down of the whole organics into usable components (nutrients).  These are then used in your garden to bolster the soil and provide added nutrients for your vegetables, flowers, etc.

The Compost Bin
The first thing you’ll need to know is where you’ll be keeping and mixing your compost.  Compost bins come in all shapes, sizes, and types.  Some are “self contained” while others are not.  Most are simple containers for holding the compost to keep it “heaped” in an optimum shape (squarish or cylindrical) and to allow air flow.

In an earlier post, I showed you how to build an extremely fast, inexpensive, and easy compost bin.  That’s a good start if you don’t want to get more elaborate.  The square-type bin (pictured here) is most popular, however.  They’re long-lasting, proven, and easy to use.

What To and Not To Compost
Just about everything organic can be composted.  For gardening, however, you’ll want to be somewhat selective.  Wastes from carnivores and omnivores (cats, dogs, humans, pigs, etc.) should be avoided for several reasons.  The main being that these can carry disease which may not be eliminated in the composting process.  They can also be overly-acidic.  Meats and fats should not be composted for these same reasons.

Here’s a short list of what to compost and what it ads. The “C” means carbon and the “N” means nitrogen.  This list isn’t complete, of course, but it contains the most common items a home garden composter will have access to.

Maintaining Compost
Your primary goal in maintaining your compost pile is to provide the optimum carbon to nitrogen content so that the decomposition process goes as quickly and as smoothly as possible.  The best ratio of carbon to nitrogen (C:N) is 25-30 to 1 (25-30:1).

So for every 25 pounds of carbon-rich items you’ve put into the pile, a pound of nitrogen-rich items should be added.  Of course, it’s very easy to be overly analytical with this and spend a lot of effort calculating what your compost heap’s ratio is.  That’s pointless and makes the process a lot more difficult than it needs to be.

The best way to tell your heap’s ratio is by smell.  When you stir the heap, which you’ll need to do occasionally, you’ll get some interesting odors coming off of it.  When the heap is at rest, however, is when you’ll want to pay attention to how it smells.  If, when standing near it, you smell a rich (not too unpleasing) rotting odor, your nitrogen level is probably a little too high.

Too much nitrogen is much better than too little for a compost heap, though, so this is not as much of a concern.  Just ad more carbon-rich items.  If your heap has a real stench to it and tickles your retching instinct, it’s very nitrogen poor.  Your heap needs nitrogen and air.  So ad something nitrogen-rich, like fresh manure, and then stir it well with a heavy fork or shovel.

Another indicator of too-little nitrogen is visual during the stirring process.  If organic matter within the heap doesn’t seem to be breaking down very well and after a couple of weeks and a good stir, nothing at the center of the pile has changed much, you’ll need to ad some nitrogen.

How often you stir is dependent on the size of your heap.  Weekly is generally the norm for most garden-sized compost piles.  You’ll want to moisten it (get it wet) at least this often as well.  Compost needs to be moist in order to break down.  Chemical-free gray water, dirty pet water, or just water from the hose is fine.

Using Compost
Compost is one of the easier things to utilize in your garden.  You can ad it to the rows between your plants while growing, mix it into the soil in the spring just before planting, and mix it in or spread it heavily over soil just before winter sets in.  Or all of the above.

There is literally no such thing as “too much compost on the garden.”  The more the merrier.

Related posts:

1. General Rules of Good Soil Maintenance
2. DIY – Building a Simple Compost Enclosure
3. Building Good Garden Soil