How good of a fertilizer is bone meal and how does it compare to a granular slow release chemical fertilizer?
Two very important considerations: Bone meal is very rich in phosphorous, while blood meal is very rich in nitrogen. You need to keep this in mind when deciding to use them, so that you do not supply nutrition inappropriately or out of balance. For example, while certain plants just love Phosphorous (e.g. Tulips and many bulbs, as well as orchids setting blossoms), to certain plants (primarily Proteas and their relative), Phosphorous is a potent toxin that can kill them. In others, Phosphorous can cause imbalances that produce undesirable results. For instance, it may create a demand for nitrogen (i.e. result in an antagonism), which, if not supplied will result in stunting, poor vigour and eventual decline. Blood meal’s high Nitrogen content can, if over-supplied, cause spindly, sickly growth that never really seems to fight off disease and blight. If you educate yourself thoroughly about what each different nutrient does, and can bother with careful balancing and seasonally-appropria
