mine used to insist on roosting in their run every night just outside the pop door lol. I had to put them in the coop every night and I'd say "bedtime"as I did it. It took a good week or so of doing it every night until they caught on and started doing it on their own. Now if they're all in the run for the evening, and it's getting close to time for them to go in, I can go in and say bedtime to them and they'll start heading in on their own
I'd say just start putting them in at night. As someone once told me, they're creatures of habit. I'd be afraid they just wouldn't go in and would freeze.