Calcium in Bone Meal

[Traveler]

I have been assuming, perhaps incorrectly, that bone meal was high in not only phosphorus but also calcium. My Vigoro brand 3-18-0 bone meal pellets have no mention of calcium on the package. Also, when reviewing options on Amazon, most bone meal products don't mention calcium. Is it possible my bone meal contains no calcium?

Is there a preferred product for adding calcium? Calcium Nitrate seems like a good option for early in the season. However, the high nitrogen content seems too high for later in the season.

[Whwoz]

Bone meal should have Calcium in it. The lack of a level on the package indicates that in has not been measured, maybe an internet search will give you an approximate level.

As to form of Calcium that is best for your soil, it depends upon the nature of your soil. Various forms of lime exist, plus gypsum and other Calcium salts. Depends a lot on your soil pH, no point adding lime to an already alkaline soil for example.

[zeuspaul]

I add crushed egg shells to my soil. They can take a long time to break down. One can powder them in a blender or food processor to speed the process. They do break down. I probably have several years of them in the soil at various stages of decomposition.

[bower]

Calcium content of bone meal is said to be around 12-13%.
@zeuspaul do you dry the eggshells before crushing them? I've been throwing them into my compost but they don't crush that easily in the damp context of coffee grounds and veggie scraps etc. That didn't bother me until squirrel filled my engine with handy half shells! So I need to break em up now before I put them out.

[MissS]

Bone meal is a good source of calcium and as bower said,it has 12-13% calcium. I also use gypsum, oyster shell meal and lime as sources of calcium. Lime will lower your PH so be careful with that. All of these need time to break down to become available to the plants so it is best to add them in the fall or as soon as the soil thaws in spring. Cal mag is a quick acting source than can be sprayed onto your plants in a pinch which is made with calcium nitrate. I use it only if I need it due to the nitrogen content.

[JayneR13]

If you're in need of a faster acting solution, I use a fertilizer called Humboldt's Secret Cal-Mag + Iron. It's a liquid formulation that can be added to the soil or foliar sprayed. There's also a product called Stop Rot, which is usually used for BER in tomatoes, but it does contain calcium.

[zeuspaul]

@zeuspaul do you dry the eggshells before crushing them?

My egg shells dry on the counter in a large coffee can. As the can fills up I tamp down with a pestle. When I have enough I pulverize with a food processor. I use some in my seed starting mixes to help with drainage a la perlite. The rest goes into my container mixes. I vary the size by processing longer depending on what I want.

Egg shells are about 95% calcium carbonate.

[Tormahto]

Don't breath in bone meal dust. Today, there's no shortage of masks to wear. I'd also avoid getting it on exposed skin.

I mostly use eggs two at a time. I rinse the shells off, dry them, and have a gallon zip-type freezer bag to put them in. When I have enough of them, they go through the food processor.

[Seven Bends]

Don't breath in bone meal dust. Today, there's no shortage of masks to wear. I'd also avoid getting it on exposed skin.

Why? Lead contamination, or bovine spongiform encephalopathy transmission, or something else?