According to the MSDS for Miracle Gro Indoor Plant Food it contains Phosphoric acid, Potassium hydroxide (K(OH)), Urea, and Sorbitan, monododecanoate, poly(oxy-1,2-ethanediyl) derivs.
According to the manufacturer, Miracle Gro Indoor Plant Food can be used on edibles. You will apply the foam directly to planst and water as normal.