I know it seems silly that one would want to go this route, but veganic gardening is a new trend that will only become more popular with time. Why would someone want to garden veganically?
Organic in chemistry terms just means that it is carbon based. Do you remember The Coneheads skit where humans were described as "carbon based life forms?" I know the premise of organic gardening is slightly different with a focus on methods that do not use pesticides and are more environmentally sensitive. That bat guano, chicken manure, or cow manure might not be sourced from a place that uses organic practices. Tricky, I know. What's the source of the blood meal or bone meal? Many are sourced from slaughter houses on factory farms. Sure that blood and bone is organic, but has it been exposed to the elements? The only true way to determine if a nute, fert, or pesticide is organic is from OMRI-(a matter of paying a price for the sticker and adhering to a few guidelines), but that still won't tell you where it was sourced from.
With veganic gardening, one uses fertilizers, amendments, and nutrients, that contain no animal, insect, fish, or sea animal ingredients. Does that sound overwhelming? Not so much. Here's a handy guide for gardening veganically:
Nitrogen for growth-neem meal, neem cake, seaweed, and kelp meal
Phosphorous- rock phosphate
Potassium- green sand has it and other trace elements
Worm castings are okay by veganic standards, even though the manure comes from a living thing. Strange, but it works that way.