They are lovely! I grow them a lot from seeds. I get my best results with morning sun and afternoon shade. I usually feed once a week with that one tablespoon per gallon stuff .. though I make my solution a bit richer - about 1.5 tbs per gallon. To keep them blooming you need to cut off spent blooms or they will go to seed and the seed heads are sticky messes. They also seem to do better in pots than in the ground .. at least for me.
This one is Sapphire Pink Rim