Can you help with my catnip questions?

I am growing catnip outside (in planters) for the sole reason that I have read that it keeps mosquitoes away. I don't have any cats (allergies) and cats usually don't come around my yard because of the way it's walled off, and it's been weeks with nothing being munched on. But since I've never done this before I had some questions:

1) Is it actually true that mosquitoes don't like catnip or am I just wasting my time with this one?

2) Red Leaves. Two of the plants I got seemed to get transplant-shock. Their stalks and leaves have mostly turned brick-red, and they seem quite stunted. I researched it a bit and found that this could be from a lack of phosphorous in the soil. Is this actually what causes that and can it be remedied by just using a bit of Miracle-Grow or something? (Again, I'm not really worried about "organic vs non-organic" since I have no plans for anything alive to be consuming these plants).

3) If catnip is in a planter, can it winter well indoors? What kind of steps should I take if I do that?

Thanks everyone!