Managing the performance of any employee is difficult, but absolutely necessary. To do it successfully, you need to have a few fundamentals in place first:
1) A current and accurate performance-oriented job description that focuses on accountabilities. This establishes a baseline for expected performance. Without one, you'll be measuring in the dark, and may end up focusing on areas that aren't priorities, and don't drive results.
2) KPIs are always recommended. But whatever you put into place, remember that project management is expectation management, and thus not everything can be measured empirically, like budget deviation or milestones missed. It will be important to consider anecdotal or 'soft' metrics, and get team and client input on how well they communicate, motivate, handle conflict, deal with cross functional issues etc.
3) Measure fit. Too many companies fail in this regard. No matter how well the PM functionally performs as per their job description, it's equally important to measure how well they fit the company's culture, live your purpose and core values, and contribute to achieving the company's overall vision.
If you have a capable PM, with strong self initiative, a weekly meeting should be the bare minimum. That said, a quick 5 minute huddle at the beginning of the day is recommended – especially for new hires still in the process of getting their feet wet – followed by another quick 5 minute huddle at the end of the day to recap progress, issues etc. You can loosen or tighten this up as needed, once they begin demonstrating the autonomy and smart decision-making you expect to see.
I'm happy to jump on a call with you to talk more specifics, and lay out a plan you can follow.