Out here man,
Front Royal, Virginia
A mineral pill such as the one you describe would dissolve in water and would be available to plant roots, just as you thought. However, crushed vitamins are an expensive way to feed your plants. You can purchase a calcium, magnesium and zinc formula for just a few dollars a pound. More complete mixes that also contain iron, manganese and other micronutrients are just a little more expensive.
Aside from the monetary savings, you’d probably be better off with the plant nutrients because they are formulated to enhance plant absorption in balanced ratios.
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