Using products like Miracle Grow on a vegetable garden, will it effect the veggies?

I’m 21 years old and just purchased a condo with my boyfriend. With the warmer weather approaching I would really like to get a few tomato plants outside on our porch. A previous question I asked led me to decide against a hanging tomato basket, but I’m still going to do one just to expariment. I’ll probably do two plants in pots on the porch (very sunny) and one hanging (also very sunny in the spot where the hanging hooks are)

An answer to my previous question said that I should use Miracle Grow (I forgot what kind specifically) on the plants. But would that be “Ungreen” ? Do plant foods like Miracle Grow harm the earth? And even more important, one of the reasons I want to plant my own is so that I know exactly what goes on them (organic)…
Are there any more natural ways that I can fertalize my plant (asside from any type of animal ****. I just wont use it)…

Also, if I purchase a tomato plant pre-grown (like when its an itty bitty baby) rather than growing it from seeds, should I assume that its already been touched by pesticides? I’m planning on buying before it grows tomatos.