It's a good question. I am no expert in this area by any means, but I do have a couple of thoughts that I came up with after doing some reading. Synthetic fertilizers are usually made from naturally occurring substances that are changed to yield the desired nutrient (N-P-K, and others). Some of the chemical processes used to produce the end product, produce byproducts that can be harmful to people and to the environment. Sometimes the synthetic nutrients that are produced and used can run off from the soil or leach into the ground water, causing other health and environmental problems.

Organic fertilizers such as various plant and animal byproducts are more easily used by the diverse ecosystem found in the soil and used by the plants or converted to harmless products. These are safer for people and for the environment. In my mind, it is all about the circle of life... plants and animals eat other plants and animals producing wastes... those wastes are then used by smaller, less sophisticated plants and animals to produce wastes... and so on until you get dirt.

Just my .2 Thanks for jump-starting my brain.

~Rock~

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Silence is a true friend who never betrays. ~Confucius~