I am one of those members that bought some from MrTexas. It is a fine powder. I imagine you could sprinkle it on your container soil, but I think it is really meant to be used as a solution. It dissolves very easily and if I remember correctly, the dosage is one teaspoon per gallon. I use an old gallon plastic milk jug and do a soil drench but others use it as a foliar spray.
Hope this helps.
P.
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