Most of mine are just starting their second year too.

If they are in the ground I feel safe to use granular at this point

Anything in a pot will always get liquid.

I have 4 brand new roses and I fertilized them 3 weeks ago using Jobe's Organics Rose & Flower and I believe they responded very positively. I think that as long you go organic you don't have to worry too much about burning the plants. Just make sure you follow the directions, err on the side of caution if you want, and water it in really well. I've never used fish fert so I can't speak to the efficacy of it but I've read positive reviews on these forums. Some fertilizer is better than none?

Second year plants, they are ready for fertilizer. Espoma Rose-tone (or any of the Tones) is fine.

First year: were they bare root or own root? Bare roots, if they have bloomed, then go ahead and fertilize. Own root, then maybe half-strength of fish emulsion.