Outdoor nutes

I'm growing Blue Mystic auto flower. I have 2 stores that sell GRANULAR nutes Walmart or Lowes. Which product should I buy? I have some MG potting soil that worked pretty good. When the plants are flowering I will fertilizer them. Please I want GRANULAR nutes. Thanks

if you must use granular, osmocote.

Make sure to get low nitrogen if you're going to use them in flower...