Q.Knock out roses
What do you do when the bloom dies?

Knockout roses are what is termed "self-cleaning" roses thus they do not need to be deadheaded to re-bloom. As a matter of fact dead-heading them is highly discouraged as in doing so one may prune off some already developing growth that will become new blooms. I typically just pull off the old petals to keep things looking more tidy and leave the rest there on the bush. Keep them well watered and fed and enjoy the bloom shows. The Home Run rosebushes from Weeks Roses are also in the self-cleaning group. Here is a link to an article for you as well: https://www.gardeningknowhow.com/ornamental/flowers/roses/self-cleaning-roses.htm