Nutrients for my outdoor plants

My plants are in the ground and I was wondering when should I start putting nutrients on them and what kind? These plants are about 5 inches tall.

3rd week ish I start with a 1/4 stength Miracal grow all purpose Fertlizer, the next week i go with 1/2 strength, an work em up to full strength.

Nutes will kill you plants very quickly, So less is more, especialy with seedlings.

Edit- Wait did you use a soil with time release ferts,like miracal grow? if so you wont have to fertilize for a few months or when you see nito defency.