I’ll take bullshit if that’s all you got
Fertilizer (or fertiliser) is any material of natural origin that is added to a soil to supply nutrients essential to the growth of plants.
In reality fertilizer is nothing more than manure (usually from animals), so Frank is sort of playing on the definition in what seems to be a commercial since he is flipping through channels. Also, this seems like a play on difference in class (high class would call it fertilizer and low class would call it shit).
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