I have 6 pullets, all about 5-6 weeks old. They mostly have adult feathers, but the our coop isn't insulated and I don't have power out there for a lamp. It's spring but the east coast is still pretty chilly and getting into the lower 50s at night. Would they be okay to live outside now? I have been weaning them off of the heater and only keeping it on at night, but sometimes when I go to turn it on at night they're huddled together.