Originally Posted by
StuckInYYZ
Egg shells you can toss into the compost pile (or if you're inclined to break out the pestle and mortar or an old coffee grinder, you can blitz them until they're near powder and sprinkle in the garden or feed to chickens if you raise them). Meat bones (if you have the time and patience) you can make into bone meal and also add to your garden (bone meal helps with roots and fruiting... the P in NPK). The disadvantage is that you need to boil the bones for 4-6 hours and then when they dry out, break them down with something. Boiling them down will dissolve any soft tissue as well as any meat.... but smells pretty bad.
My parents feed their egg shells to the birds, but if I did that (I live in a city), or put them in my compost pile, I'd be seeing a lot of rats. No thanks! Re: meat bones and making bone meal, I draw the line at that much labor/hassle to make something that you can buy for a few bucks. (Like the one time I decided to grow fava beans, and spent money for seeds plus many hours of labor of planting, harvesting, and shelling to end up with maybe two cups of actual beans!)