I'm a new grad that was hired on full time in a busy emergency department immediately after I graduated. First and foremost, although you state you don't feel that all new grads are like this, it certainly does come off that way. I think it's unfair that you're generalizing all new grads based on the behaviours of the new grads in your facility. Many of us are hardworking, passionate and competent nurses that strive to learn and continuously improve our practice. I know of many new grads that are responsible and professional, despite the ongoing obstacles we face as a result of being "new grad nurses". So while it's unfortunate that the new grads in your department are lacking in some of these areas, I assure you this is not the case across all new grads entering practice.
In terms of this on going issue within your department, I think we can revert back to practices that are common in nursing school
: evaluations. Document examples of what these nurses are doing well and what areas need to be improved upon so it's not entirely a list of what each individual is doing wrong. Discuss ways in which improvements can be made or how to refine current practices. Once this initial evaluation has been made, follow up with these new grads and track their progress. Reiterate to these nurses that you want to see them succeed and be the best that they can be. I agree that sometimes new grads can have difficulty being open to feedback, but as someone pointed out earlier, the approach can influence how these individuals perceive the feedback to be.
My department educator makes an effort to follow up with me on a biweekly basis to ensure that I am not left to fend for myself, or to discuss any issues or concerns that I have about anything related to the job. Perhaps you're already doing this, but if not, it's a good place to start.