Knockout roses - Water? Fertilize?

[Schila]

I have some knockout roses on my bed flower and yesterday I decided to cut the dead blooms mostly for appearance and guessing that it would help it to bloom again. How much water does knockout roses need? How about fertilizer? Any fertilizer in particular? Can I grow knockout roses in containers? What kind of soil for container?

[Schila]

but any fertilizer with a high central number (NPK=leaves, flowers, roots) will encourage more blooms.

Sorry, but I'm kind of new with this about the NPK. When you say high central number are you talking about the Phosphate? Phosphate higher than the rest of the numbers?