Depending on what kind og MG soil, yes you can use it. But you will need the kind that has no time release nutes in them. Im currently using the kind that has only starter nutes with no release time. And so far im doing well.
fox farm is great stuff good nutes place groworganic.com [peacefulvalley farm supply- 25 yrs plus organics for food farmers]
am seeing organic nutes in garden shops much more often then even a few years ago any organic balanced veggies food with trace minerals will work well and they don't usually give a chemical taste like MIR.Gro. and sometimes peters or scholtzs [sp] kelp /seaweed is real good to add to dirt or hydro
worm castings humic acid real good fish emulsions real good
this should help you in any local garden store
warning bat/bird guano is good but it is real easy to use too much of it....
get a gardening book for vegetable gardening beginers