I see no one has asked so I will,

If you were not ready to flower, why would you use a bloom fertilizer?

What you need during vegetative growth is high (N) Nitrogen and not high (P) Phosphorus.

But to answer your question, a picture is worth a thousand words. If the yellowing is from lack of (N), I guess any (N) even from a bloom fertilizer is better then none at all

I know you said you have not used it yet so go get some MG patio if MG is the fertilizer you want to use.