Creating your own compost is easy and provides an excellent natural fertilizer.
Compost is a mixture of organic materials - leaves, manure, table scraps and more - left in a pile to decay. Naturally occurring soil organisms will work on the material and eventually break it down into a fine, homogeneous soil additive for your vegetable garden.
Making a compost pile takes only a modest amount of effort. Start small and work your way up. Select an area about 10 feet (3 m) on a side, or a circle about 10 feet in diameter. If you have a pile of leaves raked from Fall, that's a great beginning. Over the year you can add grass cuttings, straw, vegetable leftovers or any other organic material you have lying around.
Eventually you want to make a pile from 3-5 feet (1-2 m) high. Flatten the top and make a small indentation to trap a small amount of rain water. You don't want to keep the pile too wet, though. It should have plenty of air circulation and excess water keeps out air.
That air provides oxygen that feeds the organisms that break down the material. At the same time, the pile shouldn't be too loose. Once it reaches a certain size and stage of chemical activity, the pile will begin to heat. You don't want that heat to escape too readily, since it helps keep the reaction going.
To beef up the value of the compost you can add a number of compounds that are not intended to be broken down, but will add to its eventual use as fertilizer. Raw bone meal, ground rock phosphate and lime make for good additions, though they're not the only ones.
Layering the compost pile with vegetation and these additives is a good idea. When you have a layer about a foot deep, pour on some rock phosphate. For a 100 square foot compost a total of five pounds should be plenty, so add an amount proportional to how much compost you've accumulated. A pound of limestone will serve for the total pile.
Alternatively, you can add a layer of manure a few inches high for every foot of compost. However, if you have that much manure, you probably don't need to go to the effort of making a compost. You already have in hand an excellent natural fertilizer with plenty of nutrients for your vegetable garden. If you want an extra rich compost, though, this is one way to enhance it.
When the compost pile has been active for a few weeks, you can stir up the material to keep it uniform. Organisms may be more populous in one area than another. One area may be substantially decomposed while another has barely altered. Rotating the layers will give you a more even fertilizer that is ready to go more or less at the same time. That way you know you are spreading the same concentration of nutrients at every point in your garden.
Once the pile is ready to use, you can spread it over the entire garden area if you have enough to supply about 25 pounds for a 100 square feet garden area. If not, simply apply it in those areas where the vegetables will be planted. Spread it over the topsoil about three weeks before planting and you will create a rich earth for your vegetables.