I usually suggest 1-2 weeks. My method of judging if it's time to try letting them meet face to face is to wait until the adults have mostly lost interest in the chicks. My last group of chicks got to come out for a supervised face to face meeting after about 8 days of see but no touch, while the adults were dust bathing and not too inclined to chase after them.How long do you suggest? My 2 Jumbo heirlooms are pretty mellow and lived on a farm, but the battery hen may be the one to watch out for. She's small but she no play.