When can start as soon as they are comfortable where they are.
At first only let them out when you have the time to stay and monitor them. You can take them on walks. If they don't follow you, you can herd them.
You can herd them when it is time to go in for the evening. Make sure you...
You should separate them from the other poultry. They still need a high protein turkey or game bird starter feed.
Your other poultry are probably keeping them from the feed and water.