Your off to a great start, I havent even started my seeds yet.They do need to be hardened off just like veggies, you'll need to wait til all danger of frost is over, the rule of thumb is to wait til Mothers Day. I would hold off transplanting as long as possible, the less you disturb them the better. I'm sure someone will come along with more advice for you. Good luck, you've done a good job!
Christine

They look really healthy and happy! When can you usually plant out in your area? I don't think you started to early.

Yes they need to be hardened off - any plant needs time to adjust to real sun and wind slowly - even things the were wintered over.

Dahlias, peppers and eggplant like heat, but everything else can start going out as soon as you have warmish (above 50) days. Petunias, agastache, viola and verbena can easily handle nights in the mid 30's. To much cold will slow them down, but won't really harm them.

It is the 5 days without water that I would be worrying about.

Good to know that all of my flowering plants (except the dahlias I guess) can go out soon. I'm thinking of transplanting the petunias (some have already started to bloom) in row containers in front of my house and bringing them in when temps are not favorable at night.