Here's a timely article to read on the subject, just out in National Geographic:
It sure would be easier to just sprinkle a little concentrated nitrogen compound on my garden than hauling big bags of compost and building piles to make my own. After shopping for and getting a couple of bags into my community garden plot today I didn't have energy for much else. And I need to clean up one bin and spread another of the homegrown stuff.
But the dark sides of synthetic fertilizer are many: algal blooms, soil depletion, greenhouse gases, explosions.
I've really just looked at the pictures so far, but I hope to read this article soon - after I finish the spring hauling of organic garden amendments.