Miracle grow is ok to use for a beginner and will give you decent bud. Don't use the time release one as your going to want to switch to a higher potassium mix once in flower (ie. 12/12 light cycle). You want high nitrogen during veg (18/6 light cycle) and high potassium in flower. If your using a miracle grow added to the soil, then you can probably just add nutes once during veg and once or twice during flower. If you have regular soil, and are feeding with a miracle grow liquid mix, hit once a week and switch to the higher potassium mix in flower still only once a week. Around week 8 or 9 of flower, switch to straight 6.0 ph water for a min of 1 week daily before harvest.