When I did a lot of landscaping as a teenager and in my early 20s, I was using bone meal for almost all of my plantings, but then I learned about the risks and studied organic gardening and learned about a few superior products.
Mad Cow Disease (Bovine Spongiform Encephalopathy) Concerns
Since the mid-1980s and especially the late-90s, there has been concern as to whether using bone meal for plants might be harmful, as inhaling bone meal dust can cause a form of Mad Cow Disease in humans.
In the SOUL Organic Land Care Standard, it says using bone meal is “Permitted only if guaranteed free of specific risk materials (e.g. prions associated with Mad Cow Disease). Use is strongly discouraged due to the potential spread of prion diseases.”
It’s fairly difficult to guarantee the bone is free of prions, since the nerves run through the bones, so most of us organic gardeners just don’t use it.
Most “experts” claim there is little risk to humans from using bone meal for plants, as do some studies, but there are some people out there who keep better tabs on it than most of these experts and they are seeing disturbing trends.
I won’t get into the science here and I don’t pretend to understand it all, but I know enough to stay away from using bone meal in my organic garden.
Besides, I use something that is much better.
What Is The Purpose Of Using Bone Meal For Plants?
Bone meal supplies phosphorus and a few other elements, but conventional and organic gardeners mainly use it for the phosphorus because it is supposedly important for root development.
The thing is, plants are much more complicated than that. They need many nutrients for root development, and phosphorus is actually implicated in many different plant processes, not just root growth.
The other things is, how do you know you need phosphorus? Maybe your soil has enough or too much already, and adding more might just throw the nutrient balance in the soil more out of whack.
Adding any concentrated minerals just for “good measure” is inappropriate, as it can set off a string of unintended reactions in the soil. Good organic gardening practice is to add specific minerals only when you know you need them, generally based on a soil test, and using bone meal for plants is no different.
What Should You Use Instead?
What you use instead of bone meal for plants depends on how much effort you want to put into this, but the cost isn’t much and neither is the time. There are the 3 products I generally use when planting in my organic garden.
These are in order of importance, in my opinion, so if you just want to keep it simple, use the first. I'll talk about them in my next article.