If I need to, I buy any compost which suits the plants, then feed with MiracleGrow. Better still, we make our own compost from all our veg and plant leftovers - I haven't needed to buy commercial compost for ages.
I use homemade compost over the garden for the worms to drag down and compliment the soil, and I buy multipurpose for pots and special compost for hanging baskets. I can`t be bothered with all the technicalities of making my own.