Re. bone meal: These instructions are from "Dr. Pitcairn's Complete Guide to Natural Health for Dogs & Cats" (p. 38):
"Wash the eggshells right after cracking and let them dry until you have accumulated a dozen or so. (Each whole eggshell makes about a teaspoon of powder, which equals about 1,800 milligrams of calcium.) Then bake at 300 deg. F for about ten minutes. This removes a mineral-oil coating sometimes added to keep eggs from drying out....Grind to a fine powder with a... blender...[so] that there are no sharp, gritty pieces."
I originally adopted this method because Mad Cow Disease reduced the amount of bonemeal available in the edibles market and spiked the price way up. We always have eggshells around here (we eat eggs), and until then had only crushed the shells for the compost bin. Now we bake them, powder them, and put them in the bonemeal jar for our dogs (some meals need to be supplemented with calcium). When it's full, the compost gets the powdered shells, not baked.
This will provide calcium for your plants.
Cynthia H.
Sunset Zone 17, USDA Zone 9