The following blog post was written by PleasantvilleRecycles.org members Sharon AvRutick and Christin Ogryzlo.
When buying commercial fertilizer you will come across three numbers on the package, such as 10-10-10. The numbers refer to the N-P-K ratio of the mixture: In this case, 10 percent nitrogen, 10 percent phosphorous and 10 percent potassium. Plants need these nutrients, but they are not enough.
In addition, relying on mineral fertilizer is what illegal drugs are for athletes—you can immediately see great results but consequently your plants and lawn will depend on it. The higher the amount of mineral fertilizer used, the more intensive is the erosion of the soil, the poorer the soil’s humus content, plus the environment is more polluted. A catch 22 situation that you can avoid by using compost.
Compost contains macro and micronutrients that are often absent in synthetic fertilizers. What would it cost to buy all the valuable nutrients in a cubic yard of compost? Here’s an example:
1) Fertilizer (N-P-K): A cubic yard of good compost will contain the same amount of nitrogen, phosphorous and potassium as $150–170 worth of fertilizer.
Over time the microbes in the compost will collect nitrogen (N) from the atmosphere and give it to the plants as needed. This is additional and free nitrogen. Also the nitrogen release from compost does not pollute or create toxic nitrate in our foods (fruits and vegetables).
2) Fertilizer (Minor Nutrients): Sufficient iron, calcium, sulfur, magnesium, zinc, copper, boron, manganese and molybdenum would cost $7.
3) Fertilizer (Trace Elements): Compost will contain over 65 trace elements that are naturally found in plants. You’d have to buy over $50 worth of fish emulsion to get the same amount of trace minerals.
4) Energy: Bacteria, fungus, earthworms and other life forms that live in the soil rely on energy from the carbon it contains. The amount of dry molasses needed to provide the energy found in one cubic yard of compost would cost over $150.
Dry molasses is an excellent energy source as it contains many types of complex sugars that provide fuel for soil life. The energy in dry molasses is available immediately but is quickly used up versus compost where the energy takes a few days to be available but lasts for months to years.
5) Organic Matter: Organic matter is critical for healthy fertile soil. If humates are used as a source of organic matter, it would cost over $100.
Humates are often used as a source of organic matter. Studies have shown that good mature compost will contain up to 70 percent of humic substances.
6) Microbes: Compost is teeming with beneficial microbes. It would require over $100 worth of microbial inoculants to provide the same amount of microbes and would not even be close to providing the same value or diversity.
Research has shown that microbial inoculants can have a tremendous benefit on plant growth and health. The best inoculants on the market have only 100-200 species of bacteria and 20-30 species of fungi and very few protozoa, nematodes, arthropods or other beneficial life forms. By comparison good compost will easily have 25,000 species of bacteria, 10,000 species of fungus, many species of protozoa and beneficial nematodes to cycle nutrients, prevent disease, and create soil structure.
7) Growth Hormones: Compost naturally contains many hormones that promote plant growth. It would require at least $5 of hormones to provide a similar benefit as found in one cubic yard of compost.
Research is just beginning to identify and understand the many substances in good compost that promote plant growth. These range from enzymes and hormones to vitamin like substances. Numerous studies have shown that compost helps all plants grow better (faster, stronger and healthier).
Add it up and you’ll see that one cubic yard of compost provides the same value as about $562 worth of other products!
That's why COMPOST is referred to as BLACK GOLD.
Adapted from Why is COMPOST called Black Gold? or “The Real Value of Compost "[pdf] [see pdf for references] provided by Nature’s Way Resources, an organic composting facility in Texas. NWR has been recognized in many publications from The Houston Chronicle to The Wall Street Journal for the quality of its products.