When you say "Compost" what exactly do you mean? What is it made of or from and you talk like you have some guaranteed analysis.
Or could it be that the "Compost" is just as random as topsoil, which is actually compost in my opinion is it not?
So what are we really talking about here.
Not trying to be a dick. Just opening up the conversation a bit.
The OP is even talking about "Organic" compost.
That sounds a lot vague to me.